Hand - Amputation, Replantation, Dupuytren's Flashcards
A 46-year-old woman sustains a ring avulsion injury to the long finger when the finger becomes caught in a machine. Emergent revascularization is performed; on examination 10 days later, the patient has the findings shown in the photographs above. Which of the following techniques is most likely to provide optimal function?
(A) Resection of all nonviable soft tissue and coverage with a full-thickness skin graft
(B) Resection of all nonviable soft tissue and coverage with a neurovascular island flap from the ring finger
(C) Resection of all nonviable soft tissue and reconstruction with a toe-to-hand transfer
(D) Revision amputation at the level of the mid proximal phalanx, with trimming of the bone to a level at which it can be covered primarily by viable skin
(E) Ray amputation of the long finger, leaving the base of the metacarpal in place
The correct response is Option E.
Ring avulsion injuries are typically associated with the highest failure rates following replantation, most likely because of the mechanism of injury, which involves destruction of the intimal layer of the supporting vasculature. In this patient, revascularization has failed, leaving a necrotic digit.
The most appropriate next step in management of this patient is ray amputation, which involves removal of the entire digit and most or all of the metacarpal. Completely removing the digit eliminates the segmental loss and greatly improves both function and aesthetic appearance, as shown in the photographs above.
Resection of nonviable soft tissue results in exposure of the phalanges and tendons. A full-thickness skin graft will not take over these exposed structures.
The Littler neurovascular island flap is based on the digital neurovascular bundle of either the long or ring finger. This flap provides sensate coverage of smaller digital defects, particularly the thumb, but would not cover the entire defect in this patient.
Replacing the long finger with a toe-to-hand transfer is impractical, as the transferred digit would be significantly shorter than the adjacent digits and would ultimately impair their function. This technique is appropriate for patients who have sustained amputations of the thumb or of multiple digits.
Simple revision amputation is the easiest method of skin closure but leaves a large gap between the long and small fingers, allowing an area through which small objects can fall, and thus limiting hand function.
A 38-year-old right-hand–dominant man is evaluated in the emergency department 4 hours after amputating the left thumb and index finger with a circular saw. Microvascular replantation surgery is planned. Which of the following is first in the sequence of repair?
A) Artery
B) Bone
C) Nerve
D) Tendon
E) Vein
The correct response is Option B.
When multiple digits are amputated, thumb replantation takes priority. If the amputated thumb is not suitable for replantation, the best available finger is replanted in its position. If there are injuries to other fingers or parts of the hand, they should be repaired first before replantation. In a mutilated hand, functional preservation takes priority. Procedures that ensure maximal function must be done first because the hand should not be disturbed after replantation. The sequence of repair of structures in multi-digit replants can be performed either digit-by-digit or structure-by-structure. While structure-by-structure is more efficient, warm ischemia time tends to be longer. If the thumb is involved, it is preferred that the thumb be replanted first followed by the remaining digits.
After debridement, vessels and nerves should be identified and tagged because they may be more difficult to locate after bone fixation. The sequence usually is bone fixation, tendon repair, and then vessel and nerve repair. Bone shortening facilitates repair of structures without tension. Bone fixation is performed first and should be stable enough to undergo the rigors of hand therapy. After bone fixation, the volar structures are repaired by structure type (i.e., flexor tendon, then the artery and nerves) followed by the dorsal structures (extensor tendon and veins).
A healthy 30-year-old woman is brought to the emergency department three hours after sustaining an amputation injury to the thumb and fingers of the dominant right hand when it was caught in an industrial roller. The amputated digits were placed in dry cloth, placed on ice, and transported with the patient. Physical examination shows amputation of the thumb through the interphalangeal and metacarpophalangeal joints. The amputations of the index, long, ring, and small fingers are through the proximal phalanges. Severe crush injuries are also noted in the thumb and index finger. Which of the following is the most appropriate management?
A) Debridement of the stump and completion amputation of all digits
B) Part-by-part replantation of the long, ring, and small fingers followed by completion amputation of the thumb and index finger
C) Part-by-part replantation of the thumb and index finger followed by digit-by-digit replantation of the long, ring, and small fingers
D) Digit-by-digit replantation of the thumb and index finger followed by part-by-part replantation of the long, ring, and small fingers
E) Heterotopic replantation of the long finger to the thumb position, ring finger to the long finger position, and small finger to the ring finger position
Correct answer is E.
Contraindications to replantation of hand and digits include the following:
- Upper extremity time in the proximal to mid forearm with ischemia time greater than six hours
- Concomitant life-threatening injuries
- Multiple level injury
- Severe crush or avulsion injury
- Extreme contamination
- Systemic illness or surgical history precluding replantation
- Self-mutilation cases and psychotic patients
The patient described has a mutilating hand injury with severe, multiple-level, crush amputation to the thumb and index finger rendering them unsuitable for replantation. Heterotopic replantation or transpositional microsurgery is the replantation of a digit in a nonanatomic location when the native digit is unsuitable or unavailable for replantation. There is no definitive rule for heterotopic replantation in cases of mutilating hand injury. The restoration of prehensile function is the primary goal in reconstruction following mutilating hand injuries. The thumb accounts for 40% to 50% of hand function. Other goals include establishment of at least two digits for tripod pinch, functional web spaces, wrist stability, transverse and longitudinal arches of the hand, and aesthetically pleasing appearance. Amputated digits may be replanted at the thumb position to provide restoration of prehensile function. Although establishment of index and middle fingers may be more aesthetically appealing, the use of the long and ring finger and the intervening longer web space will aid in tripod pinch. Priorities in hand reconstruction with heterotopic replantation following mutilating hand injury should be individually tailored to the clinical situation. Digits may be replanted “digit by digit” or “part by part.” “Digit by digit” refers to complete replantation of one digit at a time. A “digit-by-digit” repair is suitable in cases where the amputated digits have differing warm ischemia times and the digit in the best condition is replanted first in a salvage effort. “Part by part” refers to grouping the repair of a similar part for all amputated digits. Although the exact order of replantation is controversial, it typically starts with skeletal fixation before soft- tissue repair. The order is typically flexor tendons, extensor tendons, arteries, and veins. Arteries are typically repaired first, because venous efflux allows identification of veins for anastomosis. Some authors advocate venous repair first in guillotine amputations to reduce venous stasis and operative time from blood in the operating field. A “part-by-part” approach is generally used when the amputated digits all have the same degree of ischemia. Closure of the amputated stumps would not make use of the other digits for replantation. Although restoration of pinch is important, replantation of the severely crushed thumb and index fingers in any order would be inappropriate and would not likely survive. Replantation of the long, ring, and small fingers alone would leave the patient without a working thumb and pinch grip.
A 24-year-old, right-hand–dominant man is brought to the emergency department after sharp amputation of the index, long, and ring fingers of the left hand at the middle phalanx level sustained in a rollover motor vehicle collision. The digits are appropriately preserved. Before replantation surgery is performed, which of the following is the most appropriate next step in management?
A) Administer aspirin orally
B) Administer subcutaneous heparin
C) Obtain cervical spine x-ray
D) Obtain x-rays of the hand and digits
E) Predissection of the amputated digits
The correct response is Option C.
The NEXUS Criteria were developed to help physicians determine whether cervical spine imaging could be safely avoided in appropriate patients. The NEXUS literature defines a distracting injury as “a condition thought by the clinician to be producing pain sufficient to distract the patient from a second (neck) injury.” Similarly, the Canadian C-spine rule describes distracting injuries as “injuries […] that are so severely painful that the neck examination is unreliable.” It also must be recognized that the surgeon and ER staff can be “distracted” by what appears to be the overwhelming injury. Trauma evaluation algorithms strictly apply.
A patient involved in a rollover motor vehicle accident has significant mechanism of injury to warrant a complete trauma evaluation.
All other answers here are appropriate to prepare for the operating room AFTER the initial trauma clearance is obtained.
A 29-year-old man presents with nail pitting, leukonychia, and crumbling of the nail plate. A photograph is shown. Which of the following is the most likely diagnosis in this patient?
A) Arsenic toxicity
B) Human immunodeficiency virus
C) Lichen planus
D) Psoriatic arthritis
E) Subungual melanoma
The correct response is Option D.
Psoriatic arthritis often presents with auto-fusion of the small hand joints and diffuse fusiform swelling of the digits. This psoriatic dactylitis or “sausage digit” is caused by inflammation of periosteum, tendon, and tendon insertions. Nail deformities include pitting, leukonychia, nail crumbling, and onycholysis (separation of nail plate from bed). Nail deformities affect approximately 80% of patients with psoriatic arthritis, and 50% of patients with psoriasis.
Nail lichen planus (NLP) is characterized by thinning, longitudinal ridging, and distal splitting of the nail plate. NLP is usually resistant to topical corticosteroid therapy, but successful treatment has been reported with intralesional or systemic administration of corticosteroids.
Characteristic skin lesions of arsenic poisoning include hyperkeratosis and Mees’ lines. Mees’ lines are prominent transverse white lines in fingernails or toe-nails due to arsenic deposition in keratin-rich tissues.
Subungual melanoma has distinct cutaneous nail manifestations such as brown or black streaks in the nail without any known injury, streaks on the nails that increase in size, or a “bruise” on the nail that will not heal or move up as the fingernail grows. One of the key indications of subungual melanoma is known as “Hutchinson’s sign.” This is when a person has a streak that extends from the tip of the nail down to the nail bed and into the eponychium.
Nail disorders in HIV-infected patients include clubbing, splitting of the nails, or discoloration (black or brown lines going either vertically or horizontally).
A 54-year-old man presents to the emergency department with increasing right forearm pain and a rapidly enlarging pulsatile mass 4 days after suture repair of a proximal right volar forearm laceration. At the time of injury, significant blood loss in the field and pulsatile bleeding in the emergency department was noted. The hand is perfused, and sensation is grossly intact to pinprick. Which of the following is the most appropriate next step in management?
A) Incision and drainage of the laceration at bedside
B) Inpatient admission for observation
C) Magnetic resonance angiography
D) Needle manometry
E) Operative exploration
The correct response is Option E.
The history and presentation are concerning for a ruptured pseudoaneurysm. Although the patient’s hand is perfused, the rapid onset of pain and swelling is concerning for active bleeding. Appropriate management would consist of operative exploration and repair of the injured vessel. Imaging studies can confirm the diagnosis in the setting of a post-traumatic pulsatile mass, but they would not be appropriate in the emergent setting described. Observation would result in ongoing hemorrhage, which could be life-threatening or result in a compartment syndrome. Bedside incision and drainage could result in bleeding in an uncontrolled environment. Needle manometry is employed to provide adjunctive data in the assessment of potential compartment syndrome, but it would not be appropriate in the setting of potential uncontrolled hemorrhage.
A 21-year-old man with a crush injury to the right forearm is evaluated because of severe pain at rest and with passive range of motion 24 hours after he was released by the emergency department. The patient reports no paresthesias. Which of the following assessments is the most appropriate next step in management?
A) Compartment pressures
B) CT scan
C) MRI
D) Ultrasonography
E) Urinalysis
The correct response is Option A.
The patient described sustained a crush injury, and subsequently experienced increased pain in the affected extremity. He ultimately experienced pain upon passive motion as well. This scenario should elevate suspicion for compartment syndrome. Other signs and symptoms of compartment syndrome include paresthesias, which this patient did not have, as well as poikilothermia, and pulselessness, which is a late finding. Compartment syndrome can be the result of high-impact trauma or low-impact injury, and it should be identified as early as possible to prevent permanent disability. Therefore, the next best step in the care of this patient is measurement of compartment pressures to determine if fasciotomy is necessary to release the build-up of pressure in the forearm. Radiological imaging will waste time and possibly worsen the patient’s prognosis. Urinalysis should be performed as part of the patient’s overall workup in order to assess the potential for acute tubular necrosis, but it is not the definitive next step.
A 5-year-old boy presents with deformity of the tip of the left long finger as shown in the photographs. The tip of the finger was amputated one year ago, and the wound was repaired at a local emergency department. Which of the following is the most appropriate method of correcting this deformity?
A) Coverage with a hypothenar flap
B) Distraction lengthening of the distal phalanx
C) Free toe transfer
D) Nail bed grafting
E) Release and augmentation of hyponychium
The correct response is Option E.
This is a classic hook nail deformity and is caused by deficient bone support of the distal nail bed, soft-tissue contracture/deficiency of the tip of the finger, or both. The most appropriate way to correct the deformity is release and shortening of the portion of the nail bed that has no underlying bone support, and augmentation or advancement of the distal soft tissue envelope. There are many correction methods described, including some that add both soft tissue and bone support of the overhanging distal nail bed. Regardless of method chosen, the primary goal of correction is to release the tethered nail bed, ensure that it is supported by bone, and provide sufficient soft tissue coverage to negate tension on the distal nail bed. Nail bed grafting alone will not correct this deformity as this does not provide additional bone support for the nail bed. A hypothenar flap is too remote to supply tissue for this problem. Lengthening the distal phalanx using bone grafting or vascularized bone has been described, but the use of distraction osteogenesis is impractical. Because most of the finger remains in place, a free toe transfer is not indicated.
Composite grafting could conceptually address this issue and has been described, but the survival of the graft is not predictable and harvest of the graft leaves a deformity at the donor digit.
A 36-year-old man comes to the emergency department 8 hours after he sustained a sharp circumferential laceration of the proximal forearm. Most of the musculature is visibly transected. The distal forearm and hand are pale and insensate, and there are no discernible pulses distal to the laceration. X-ray study shows no bony injury. All structures are successfully repaired and hand perfusion is restored during a 6-hour procedure. Which of the following is the most appropriate next step in treatment?
A) Administration of an anticoagulant
B) Administration of thrombolytic agents
C) Forearm and hand fasciotomies
D) Splinting, and intravenous administration of antibiotics
E) Tissue oximetry
The correct response is Option C.
Following a protracted course of tissue ischemia, reperfusion will lead to soft-tissue and muscle edema, and there is a very high risk of compartment syndrome. Routine prophylactic fasciotomy after arterial repair has been questioned. Nevertheless, an extended warm ischemia time of greater than 8 hours and a combined injury involving both major arteries and veins have been proposed as indications for this procedure. In this scenario, the patient has both of these risk factors for reperfusion compartment syndrome, and fasciotomy of the hand and forearm should be performed before leaving the operating room.
Wound management, splinting, intravenous administration of antibiotics, and monitoring of hand perfusion are important postoperative modalities, but they are not as temporally relevant as fasciotomy. The use of thrombolytic agents is not indicated in this setting because the perfusion was restored and there is no reason in the vignette to suspect evolving thrombus formation. The routine use of anticoagulant after uncomplicated vessel repair is controversial.
A 47-year-old woman is brought to the emergency department 30 minutes after sustaining an amputation injury to the dominant right hand. The amputated part was wrapped in a wet towel immediately after the injury and has been kept on ice since that time. Physical examination shows a guillotine-type amputation of the hand at the distal aspect of the palm with minimal injury proximal and distal to the amputation. A photograph is shown. Which of the following structures is expected to have the poorest recovery following successful replantation?
(A) Extensor digitorum communis
(B) First dorsal interosseous
(C) Flexor digitorum profundus
(D) Flexor digitorum superficialis
(E) Flexor pollicis brevis
The correct response is Option B.
The first dorsal interosseous is in the zone of injury. When amputations occur through the distal aspect of the palm, the intrinsic muscles are usually injured and intrinsic function is poor despite successful replantation. Finger abduction and adduction, metacarpophalangeal joint flexion, and proximal and distal interphalangeal joint extension and key pinch are limited as a result. Debridement of injured muscle is recommended to prevent contracture and intrinsic tightness. In this setting, movement is generated by extrinsic muscle groups without the fine-tuning of motion usually provided by the intrinsic muscles.
With sharp lacerations at the level of the distal palm, the flexor digitorum profundus and superficialis and extensor digitorum communis tendons typically function well with good repair technique, appropriate rehabilitation, and occasional secondary surgery. The flexor pollicis brevis is proximal to the zone of injury.
The mechanism of injury is an important determinant in the outcome of the repair. Sharp injuries have the most discrete area of damage and therefore tend to have greater recovery of function. Blunt and avulsion €‘type mechanisms, which have greater zones of injury, require more extensive reconstruction and are associated with less complete restoration of function, including motion and sensibility. In addition to functional considerations, replantation of the amputated hand serves the patient by restoring the appearance of the hand.
A 13-year-old girl sustains a stellate matrix laceration of the right long finger when it is closed in a car door. Which of the following is the most appropriate management?
(A) Ablation of the nail bed and application of nonadherent bandage
(B) Debridement of the edges of the nail bed and split germinal nail grafting
(C) Debridement of the nail bed and creation of releasing incisions to coapt the nail bed
(D) Irrigation of the wound and healing by secondary intention
(E) Primary repair of the nail and replacement of the nail plate under the eponychial fold
The correct response is Option E.
Simple and stellate matrix lacerations of the nail bed should be managed by primary repair of the nail at the time of injury. Healing by secondary intention without anatomic alignment can result in increased scar tissue in the nail bed. As the nail plate regenerates, the nail will not properly adhere to the nail bed, causing deviation of the nail away from the finger as well as subsequent trauma and discomfort. Sterile nail bed injuries that involve lost tissue should be corrected with a sterile nail bed graft. Loss of the germinal matrix requires a full-thickness germinal matrix graft.
A 32-year-old, right-hand–dominant man is brought to the emergency department 3 hours after sustaining an avulsion injury to the left thumb. The avulsed digit was immediately placed on ice and transported with the patient. Photographs are shown. Replantation fails; the necrotic digit is removed and the wound closed. The carpometacarpal (CMC) joint is disarticulated. Which of the following is the most appropriate method of reconstruction in this patient?
A) Great toe to thumb transfer
B) Metacarpal lengthening
C) Osteoplastic reconstruction
D) Pollicization of index finger
E) Web deepening
The correct response is Option D.
This patient has a proximal thumb avulsion with disruption of the carpometacarpal (CMC) joint. In this scenario, the best reconstructive option (besides successful replantation) is pollicization of the index finger. Reconstruction after thumb amputation, as with congenital deficiencies, depends largely on the length of the remaining skeletal structure. One can lose most of the distal phalanx and still retain good overall thumb function. Amputations that involve the proximal phalanx or the metacarpal suffer from deficient bone length and procedures that add length, like distraction, toe to thumb, or osteoplastic reconstruction. When the entire metacarpal is absent, the aforementioned procedures will not be effective. Pollicization will restore thumb length and provide very good function.
A 55-year-old man with well-controlled type 1 diabetes mellitus and a history of kidney transplantation comes to the clinic because he has had increasing pain, swelling, and redness of the right index finger over the past four days. Five days ago, he sustained an injury to the finger when a thorn became lodged under the skin while he was gardening. Medical records show that hemoglobin A1cwas 12% three weeks ago. Temperature is 37.9EC (100.2EF). On laboratory studies, white blood cell count is 16,000/mm3 and serum glucose level is 495 mg/dL. Examination of the right hand shows severe flexor tenosynovitis of the index finger. Which of the following factors in this patient increases his risk of amputation of the digit?
(A) Hemoglobin A1c greater than 10%
(B) History of kidney transplantation
(C) Insulin dependence
(D) Serum glucose level greater than 450 mg/dL
(E) White blood cell count greater than 14,000/mm3
The correct response is Option B.
History of renal failure or kidney transplantation is associated with the highest risk of amputation in diabetic patients with hand infections. Amputation rates in this population range from 75% to 100%.
Multiple studies have shown that diabetes mellitus negatively impacts the prognosis of hand infections. Hand infections in patients with diabetes take longer to resolve and are more likely to require multiple debridements than infections in patients without diabetes. In addition, initiation of treatment is more likely to be delayed in patients with diabetes. In 50% of cases, the initial surgical procedure does not control the infection adequately. Amputation rates for hand infections in patients with diabetes range from 7% to 63%. In up to 28% of patients undergoing amputation, a repeat procedure at a more proximal level is required.
Insulin dependence, history of poorly controlled diabetes (as indicated by elevated hemoglobin A1c), white blood cell count greater than 14,000/mm3, and serum glucose level greater than 450 mg/dL have not been shown to significantly increase the risk of amputation in diabetic patients with hand infections.
A 25-year-old laborer who has sustained a crush injury of the thumb. Examination shows complete avulsion of the extensor pollicis longus tendon from its insertion as well as avulsion of the dorsal soft tissues from the germinal matrix to the midproximal phalanx. The patient wishes to maintain as much thumb function as possible.
Which of the following flaps is most appropriate for soft-tissue coverage of the wound?
(A) Dermal flap
(B) Flag flap
(C) Free flap
(D) Kite flap
(E) Muscle flap
The correct response is Option D.
A kite flap will provide reliable soft-tissue coverage of this patient’s wound. This axially patterned flap is based on the first dorsal metacarpal artery; it can be elevated from the dorsal aspect of the proximal phalanx of the index finger. In order to reach distal defects of the dorsal thumb, the surgeon should dissect proximally to the origin of the first dorsal metacarpal artery, just proximal to the bifurcation of the dorsal radial artery and into the princeps pollicis artery and deep palmar arch. Although this flap is technically demanding, it will provide optimal results.
A dermal turnover flap from the index finger will not have a sufficient arc of rotation to cover this defect. A flag flap is best for coverage of defects involving the proximal phalanges or metacarpophalangeal joints of the fingers and should not be used for the thumb. A free flap should not be attempted when more simple options are available. A muscle flap is too bulky and would inhibit pinch strength, effectively limiting the use of the hand, which is unacceptable in a laborer.
A 25-year-old woman is brought to the emergency department after sustaining an avulsion of the ring finger of the left hand. The avulsed part was transported to the hospital in a plastic bag. The patient is employed as a concert pianist and her livelihood depends on successful replantation. Which of the following is the most appropriate treatment to improve survival of the finger and optimize the clinical outcome?
A) Acute bone grafting
B) Coverage of the exposed tendons with a groin flap
C) Delayed tendon reconstruction
D) Neural repair with at least eight interrupted 10-0 nylon sutures
E) Resection of the injured vessels and vein grafting
Correct answer is E.
Ring avulsion injury remains one of the most challenging replantation problems because of the large zone of injury of the soft tissues. As a result, the regional vessels are significantly damaged due to the stretch avulsion, and as such, need to be resected widely and replaced with vein grafts. Amputated parts should be transported dry in a saline-iced slurry and protected by a plastic bag. Bone grafting should be reserved for a failed union, in the subacute or late setting, while tendon repair should be performed at the time of replantation. A neural repair with more than four sutures is not necessary and may contribute to neuroma formation.
A 52-year-old man has a painless, nontender 2-cm mass in the left palm that has been stable for the past three years. He has a history of plantar fibromatosis but no history of trauma. His father and brothers have similar nodules. Which of the following is the most appropriate management?
(A) Observation
(B) Punch biopsy of the lesion
(C) Incisional biopsy of the lesion
(D) Excisional biopsy of the lesion
(E) Wide radical resection of the lesion
The correct response is Option A.
This 52-year-old man most likely has a Dupuytren’s nodule; therefore, the most appropriate management is observation alone. Dupuytren’s nodules are common in patients who have a history of plantar fibromatosis. Solitary nodules often remain unchanged for years, and only occasional follow-up examinations are required. Painful lesions can be treated with injection of a corticosteroid.
Because Dupuytren’s nodules contain abundant myofibroblasts that produce abnormal collagen, purified collagenase has been used with some success in management. Other conservative treatments including application of dimethyl sulfoxide (DMSO), interferon therapy, splinting, and ultrasonography have not been proven to be widely effective.
Biopsy is not recommended for this nonmalignant lesion. Excision of a Dupuytren’s nodule is rarely indicated.
A 46-year-old automobile mechanic comes to the office because of a 3-week history of localized pain in the fingers of the dominant right hand. He does not smoke cigarettes. He says the pain occurs intermittently and that he has no symptoms anywhere else in the body. Examination shows scattered, punctate, dark petechiae at the tips of the ring and little fingers. Rubor progressing from the distal interphalangeal joints to the tips of the ring and little fingers is noted. An additional bounding pulse is palpable in the proximal ulnar palm. Radial and ulnar pulses at the wrist are normal. Digital Allen tests show decreased flow at the ring and little fingers and the ulnar aspect of the long finger. Plain x-ray studies show no abnormalities. A photograph is shown. Which of the following is the most likely diagnosis?
A) Buerger disease
B) Congenital vasospastic disease
C) Distal embolization from the heart
D) Hypothenar hammer syndrome
E) Raynaud disease
The correct response is Option D.
This is a classic presentation for the patient who develops an ulnar artery aneurysm at Guyon canal. The aneurysm typically is the source of small emboli that tend to affect vessels at the ulnar aspect of the hand and fingers. The emboli cause decreased flow, cold sensitivity, ischemic pain and rubor in the small and ring fingers most commonly. This problem occurs most often in men in their 40s, who suffer repetitive blunt trauma to the hand. Some use their hand as a hammer at work. Other forms of blunt trauma have been linked to this problem, including certain sports and weight lifting. The treatment options include oral medications for vasodilation, cessation of the offending physical activity, smoking cessation if present, sympathectomy, thrombolytics, and either exclusion of the aneurysm and ulnar artery ligation in the palm, or aneurysm excision and vascular reconstruction.
Raynaud disease is not the best answer because this presentation with embolic disease localized to the ulnar fingers and the palpable pulse/mass (aneurysm) in the hand are not consistent with Raynaud disease. Patients with Raynaud disease typically present complaining of cold sensitivity, periods of finger blanching, followed by diffuse return of flow to the fingers and pain. Raynaud disease is a diffuse sympathetic problem, not a local aneurysmal problem.
Congenital vasospastic disease is not the best answer because the patient in this vignette has no symptoms prior to 3 weeks ago. A congenital vasospastic problem would have presented before, and would be unlikely to be so localized.
Distal embolization from the heart is wrong for similar reasons: emboli from the heart would be very unlikely to present unilaterally, in two fingers, adjacent to one another. There would very likely be other symptoms and sites of embolization.
Buerger disease is not the best answer for a few reasons. The patient in this vignette is a nonsmoker. Thromboangiitis obliterans (TAO), or Buerger disease, is an inflammatory arteritis seen in smokers. It improves or stops progressing with smoking cessation. Buerger disease does not typically present with such isolated symptoms, and can involve the lower extremities as well.
A 35-year-old man comes to the office for evaluation of a previous amputation of the dominant thumb. Medical history includes factor V Leiden mutation. The patient states that he does not want any microsurgical flap reconstruction. X-ray study shows amputation at the metacarpal base level. Which of the following reconstruction methods is most appropriate for the best aesthetic and functional outcome in this patient?
A) Metacarpal distraction
B) Osteoplastic reconstruction with iliac bone and radial forearm flap coverage
C) Pollicization of the index finger
D) Silicone prosthesis
E) Web space deepening with Z-plasty
The correct response is Option C.
The thumb is considered to account for at least 40% of hand function. Essential characteristics to provide optimal function of the thumb include mobility, opposition, sensation, stability, strength, and normal shape. Metacarpal distraction can provide a strong, stable, and sensate thumb but is not very aesthetically pleasing as it will be larger than a normal thumb and lack a nail. Osteoplastic reconstruction and flap coverage provides a stable post but no mobility and poor sensation with the same visual concerns. Web space deepening with Z-plasty can provide a very functional stable thumb with more distal amputations but would not provide sufficient length in this patient. Silicone prostheses provide excellent cosmetic digits but are not functional. The most appropriate reconstruction in this patient without a toe transfer would be an index pollicization.
A 52-year-old man comes to the emergency department because he has increasing pain and swelling of the right index finger six hours after sustaining an injury to the tip of the finger. He says he was holding a small object in his nondominant hand to paint it with a high-pressure gun when he missed the object and injected oil-based paint into the tip of the index finger. On examination of the finger, sensation is intact and capillary refill is good. Which of the following is the most appropriate initial management?
A ) Amputation of the index finger
B ) Debridement of the index finger and serial dressing changes
C ) Elevation of the hand, administration of antibiotics, and early mobilization
D ) Incision and cleansing of the underlying tissue with sterile mineral oil
E ) Observation with serial examinations
The correct response is Option B.
The patient described has a high-pressure injection injury to the index finger of his assisting hand. As with electrical injuries, the damage caused by the destructive chemicals in paint and other hydrocarbons as well as caustic cleaning solutions far exceeds the usual small and apparently innocent entrance wounds. The chemicals tend to travel down the finger and can involve the tendon sheaths with migration to the wrist, resulting in increased morbidity. The subcutaneous tissue is destroyed by either saponification or dissolution of the lipids. This situation warrants early aggressive surgical therapy. Outcome for delayed treatment is nearly uniformly poor, resulting in either amputation or permanent stiffness. The best outcomes result from emergent debridement of all involved tissue and open dressing changes. Early mobilization will assist in treatment.
Given these facts, observation for this patient is inappropriate. As his finger remains perfused and sensate, there is no need for immediate amputation. Immediate amputation is appropriate for patients who present with cool, insensate fingers. Delayed amputation may be required for finger necrosis.
Mineral oil is itself a hydrocarbon and potentially toxic and therefore not appropriate for the clinical scenario described.
The outcome for less caustic injection injury, such as water or air, is more favorable and therefore warrants less aggressive therapy. These patients can be treated with administration of antibiotics, elevation, and early mobilization with minimal or no debridement. Because the patient described had oil-based paint injected into his finger, the less aggressive therapy is not appropriate.
A 65-year-old right-hand–dominant man comes to the office because of Dupuytren contracture of the metacarpophalangeal joints of the ring and little fingers of the left hand with a 40-degree flexion deformity of the proximal interphalangeal (PIP) joint of the little finger. The PIP joint of the ring finger is not involved. He has no history of trauma. Palmar fasciectomies are performed, but no improvement of the little finger PIP joint contracture is noted intraoperatively. Which of the following is the most appropriate next step?
A) Administration of collagenase
B) Excision of collateral ligaments
C) Percutaneous fixation of the PIP joint in forced extension
D) PIP joint capsulotomy
E) Release of the checkrein ligaments of the PIP joint
The correct response is Option E.
The decision to proceed to surgery is based on the patient’s functional limitations and severity of joint contracture. A metacarpophalangeal (MCP) joint contracture of less than 30 degrees or any proximal interphalangeal (PIP) joint contracture is considered an indication for surgery. The MCP joint is rarely a problem since it can almost always be released by a simple fascial excision. If the PIP joint remains in fixed flexion, the checkrein should be examined and released. These are two ligamentous cords lying anterolaterally and running from the proximal swallowtail extensions of the volar plate to the neck of the proximal phalanx. The next structure to be released is the accessory collateral ligament running from the condyle on the head of the proximal phalanx to the lateral edges of the volar plate. Lastly, gentle manipulation may be utilized to obtain some release. Forcefully placing the joint in extension with Kirschner wire fixation is not indicated. Collagenase will not address capsular issues.
A 47-year-old woman is brought to the emergency department 30 minutes after sustaining an amputation injury to the dominant right hand. The amputated part was wrapped in a wet towel immediately after the injury and has been kept on ice since that time. Physical examination shows a guillotine-type amputation of the hand at the distal aspect of the palm with minimal injury proximal and distal to the amputation. A photograph is shown. Which of the following structures is expected to have the poorest recovery following successful replantation?
A) Extensor digitorum communis
B) First dorsal interosseous
C) Flexor digitorum profundus
D) Flexor digitorum superficialis
E) Flexor pollicis brevis
Correct answer is B.
The first dorsal interosseous is in the zone of injury. When amputations occur through the distal aspect of the palm, the intrinsic muscles are usually injured and intrinsic function is poor despite successful replantation. Finger abduction and adduction, metacarpophalangeal joint flexion, and proximal and distal interphalangeal joint extension and key pinch are limited as a result. Debridement of injured muscle is recommended to prevent contracture and intrinsic tightness. In this setting, movement is generated by extrinsic muscle groups without the fine-tuning of motion usually provided by the intrinsic muscles.
With sharp lacerations at the level of the distal palm, the flexor digitorum profundus and superficialis and extensor digitorum communis tendons typically function well with good repair technique, appropriate rehabilitation, and occasional secondary surgery. The flexor pollicis brevis is proximal to the zone of injury.
The mechanism of injury is an important determinant in the outcome of the repair. Sharp injuries have the most discrete area of damage and therefore tend to have greater recovery of function. Blunt and avulsion-type mechanisms, which have greater zones of injury, require more extensive reconstruction and are associated with less complete restoration of function, including motion and sensibility. In addition to functional considerations, replantation of the amputated hand serves the patient by restoring the appearance of the hand.
A 45-year-old right-hand–dominant carpenter comes to the office because of pain in the right hand that worsens during exposure to the cold. Physical examination shows small, distal ulcers on the ring and little fingers. The other fingers are warm, and no abnormalities are noted. Digital brachial index (DBI) of the affected fingers is 0.55 (N ≥0.7). DBI of the other fingers is within the normal range. Which of the following combinations is the most likely diagnosis and most appropriate next step in management?
A) Cubital tunnel syndrome; surgical intervention
B) Hypothenar hammer syndrome; medical treatment
C) Hypothenar hammer syndrome; surgical intervention
D) Raynaud disease; medical treatment
E) Raynaud disease; surgical intervention
The correct response is Option C.
Hypothenar hammer syndrome (HHS), or ulnar artery occlusion at the wrist, involves reduced or no flow to the areas supplied by the ulnar artery. Typically due to arterial occlusion, angiography may show areas of stenosis and ectasis (“corkscrew” pattern). In either case, there are symptoms related to arterial insufficiency. Treatment options range from medical to surgical.
Indications for surgery include digital ulceration (a late finding) and distal brachial index (DBI) of less than 0.7. Surgery may involve simple ligation and resection or require reconstruction. Typical indications for surgical reconstruction include inadequate collateral flow or inadequate circulation. Some authors suggest that a preoperative DBI of less than 0.7 is an indication for reconstruction, although others state the DBI needs to be measured after arterial ligation/excision.
HHS may initially be approached with medical treatment, but the presence of ulceration and a DBI of less than 0.7 indicate the need for surgical intervention.
Raynaud disease is a vasospastic disorder which would give similar findings to HHS, except that it would not be limited to just the ulnar digits.
A 40-year-old woman presents with small, non-healing ulcers of the right index and middle fingertips. Medical history includes limited scleroderma diagnosed 5 years ago, chronic pain, and color changes of the fingers in cold temperatures. The patient’s symptoms have not improved with administration of nifedipine. Angiography shows diffuse vascular narrowing without any focal lesions. Which of the following is the most appropriate intervention for pain relief and ulcer healing in this patient?
A) Cervical sympathectomy
B) Continuous brachial plexus blockade
C) Digital bypass
D) Onabotulinum toxin A
E) Stellate ganglion block
The correct response is Option D.
This patient has Raynaud’s phenomenon associated with scleroderma. The pathophysiology of Raynaud’s is thought to be related to sympathetic hyperactivity, elevated plasma endothelin, increased peripheral alpha-2 receptors, and possibly abnormal platelet and red cell function. Botulinum toxin type A has been shown to improve digital perfusion on laser Doppler, decrease pain, and result in ulcer healing. In a series of 33 patients injected with 50 to 100 U of onabotulinum toxin A, all patients had ulcer healing by 60 days postinjection. Pain relief typically occurred within 5 to 10 minutes of injection and complication rates were low and limited to injection site reactions. A prospective, randomized, placebo-controlled trial showed patients with limited scleroderma and shorter duration of disease had the best response to onabotulinum toxin A.
Stellate ganglion blocks have been shown to have only variable success for Raynaud’s with only short-term symptom relief and no effect on ulcer healing. Stellate blocks may not disrupt all sympathetic input to the extremity. Brachial plexus blocks may help with perfusion temporarily but are advocated mainly in patients undergoing microvascular surgery. Their use is not recommended in this setting. Surgical bypass to the superficial palmar arch has been shown to increase blood flow to the hand and improve ulcer healing. However, bypass to the digital vessels would not be indicated as the distal target vessels are often diminutive without adequate flow.
A 54-year-old man comes to the office because of an injury to the long finger of the dominant right hand sustained when it was pinched in a machine at work. Physical examination shows a 1.3-cm loss of pulp tissue with no exposed bone. To preserve function and sensation in the digit, which of the following is the most appropriate intervention?
A) Amputation at the distal interphalangeal joint
B) Cross-finger flap
C) Moist dressings
D) Thenar flap
E) Volar V-to-Y advancement flap
The correct response is Option C.
Fingertip injuries are one of the most common problems encountered in hand surgery. The long finger is the most common finger involved. The patient’s age, occupation, and compliance with treatment should be considered when determining treatment. When possible, if the patient has no exposed bone or only a small area of exposed bone, treatment with dressing changes offers excellent results. There is no donor site morbidity, scarring is often minimal, and return of sensation is generally excellent. Patients, however, need to be cautioned that a prolonged period of dressing changes is required, often lasting 3 to 6 weeks.
Amputation at the distal interphalangeal joint would result in loss of function of the profundus tendon and grip weakness. Neurovascular island flaps and V-to-Y advancement flaps offer excellent closure options when digital length needs to be preserved and there is significant exposure of bone. However, with these flaps there is a donor defect and decreased sensation. Care must be taken when using a cross-finger flap or thenar flap in older patients to avoid contractures and stiffness of the digits.
A 56-year-old woman presents for examination after undergoing completion amputation through the distal interphalangeal joint of the right middle finger 6 months ago. When she makes a composite fist, the middle finger paradoxically extends at the proximal interphalangeal joint. Which of the following anatomical structures is most likely responsible for this finding?
A) Central slip
B) Flexor digitorum profundus
C) Flexor digitorum superficialis
D) Lumbrical
E) Triangular ligament
The correct response is Option D.
The finding described is called the lumbrical plus deformity, which is paradoxical extension of the interphalangeal (IP) joint or joints with active flexion of the digits. The lumbrical muscle originates from the flexor digitorum profundus (FDP) tendon and acts through the lateral bands to extend the IP joints and flex the metacarpophalangeal (MCP) joints. When the proximal end of the FDP tendon retracts, the lumbrical muscle retracts with it, resulting in increased force of MP flexion and IP extension on the affected finger. Since the FDP has a common muscle belly, when a composite fist is made, the unaffected fingers flex and the injured finger extends. In this patient, the injured finger does not flex because the FDP is no longer attached following amputation through the distal IP joint. The central slip and flexor digitorum superficialis are not involved in this pathology. Although the FDP is involved in the pathology, the underlying pathology results from persistent and now dysfunctional pull of the lumbrical muscle. The base of the triangular ligament remains present, but it plays no role in the lumbrical plus deformity.
A 35-year-old woman is brought to the emergency department four hours after sustaining an amputation of the right thumb when it was caught in a machine at a meatpacking plant. The amputated part was wrapped in moist saline gauze and placed on ice within 20 minutes of the injury, and has 12cm of flexor pollicis longus tendon attached to the part. Which of the following factors is most likely to limit the success of replantation of the thumb?
A) Mechanism of injury
B) Inadequate bone stock
C) Initial treatment of digit
D) Possibility of infection
E) Warm ischemia time
Correct answer is A.
The extensor tendons and flexor tendons in the scenario described have been avulsed from the musculotendinous junction. In addition, the nerve ends extend proximally beyond the level of the soft-tissue injury; both of these findings are indicative of an avulsion-type injury. Such injury mechanisms often result in significant intimal injury within digital arteries, limiting the success of replantation. The amputated part was appropriately managed, and warm ischemia time was minimized. Digits have been successfully replanted with greater than 24 hours of cold ischemia time. Amputations at the metacarpophalangeal or interphalangeal level of the thumb may result in joint fusion; however, in this scenario, bone stock is adequate for skeletal fixation. Infection is a potential problem following any traumatic hand injury, but adequate surgical debridement and appropriate antibiotic coverage make replantation loss from infection a rare occurrence.
A healthy 30-year-old woman is brought to the emergency department three hours after sustaining an amputation injury to the thumb and fingers of the dominant right hand when it was caught in an industrial roller. The amputated digits were placed in dry cloth, placed on ice, and transported with the patient. Physical examination shows amputation of the thumb through the interphalangeal and metacarpophalangeal joints. The amputations of the index, long, ring, and small fingers are through the proximal phalanges. Severe crush injuries are also noted in the thumb and index finger. Which of the following is the most appropriate management?
(A) Debridement of the stump and completion amputation of all digits
(B) Part-by-part replantation of the long, ring, and small fingers followed by completion amputation of the thumb and index finger
(C) Part-by-part replantation of the thumb and index finger followed by digit-by-digit replantation of the long, ring, and small fingers
(D) Digit-by-digit replantation of the thumb and index finger followed by part-by-part replantation of the long, ring, and small fingers
(E) Heterotopic replantation of the long finger to the thumb position, ring finger to the long finger position, and small finger to the ring finger position
The correct response is Option E.
Contraindications to replantation of hand and digits include the following:
- Upper extremity time in the proximal to mid forearm with ischemia time greater than six hours
- Concomitant life €‘threatening injuries
- Multiple level injury
- Severe crush or avulsion injury
- Extreme contamination
- Systemic illness or surgical history precluding replantation
- Self €‘mutilation cases and psychotic patients
The patient described has a mutilating hand injury with severe, multiple-level, crush amputation to the thumb and index finger rendering them unsuitable for replantation. Heterotopic replantation or transpositional microsurgery is the replantation of a digit in a nonanatomic location when the native digit is unsuitable or unavailable for replantation. There is no definitive rule for heterotopic replantation in cases of mutilating hand injury. The restoration of prehensile function is the primary goal in reconstruction following mutilating hand injuries. The thumb accounts for 40% to 50% of hand function. Other goals include establishment of at least two digits for tripod pinch, functional web spaces, wrist stability, transverse and longitudinal arches of the hand, and aesthetically pleasing appearance. Amputated digits may be replanted at the thumb position to provide restoration of prehensile function. Although establishment of index and middle fingers may be more aesthetically appealing, the use of the long and ring finger and the intervening longer web space will aid in tripod pinch. Priorities in hand reconstruction with heterotopic replantation following mutilating hand injury should be individually tailored to the clinical situation.
Digits may be replanted €œdigit by digit € or €œpart by part. € €œDigit by digit € refers to complete replantation of one digit at a time. A €œdigit-by-digit € repair is suitable in cases where the amputated digits have differing warm ischemia times and the digit in the best condition is replanted first in a salvage effort. €œPart by part € refers to grouping the repair of a similar part for all amputated digits. Although the exact order of replantation is controversial, it typically starts with skeletal fixation before soft-tissue repair. The order is typically flexor tendons, extensor tendons, arteries, and veins. Arteries are typically repaired first, because venous efflux allows identification of veins for anastomosis. Some authors advocate venous repair first in guillotine amputations to reduce venous stasis and operative time from blood in the operating field. A €œpart-by-part € approach is generally used when the amputated digits all have the same degree of ischemia.
Closure of the amputated stumps would not make use of the other digits for replantation.
Although restoration of pinch is important, replantation of the severely crushed thumb and index fingers in any order would be inappropriate and would not likely survive.
Replantation of the long, ring, and small fingers alone would leave the patient without a working thumb and pinch grip.
Which of the following best describes the flap used for thumb reconstruction shown in the photograph above?
(A) Based on the dorsal metacarpal artery to the ring finger
(B) Based on the posterior interosseous artery
(C) Supplied by a terminal branch of the median nerve
(D) Supplied by a terminal branch of the radial nerve
(E) Supplied by a terminal branch of the ulnar nerve
The correct response is Option E.
The photograph illustrates Littler’s neurosensory island flap, which is based on the proper digital nerve to the ulnar aspect of the ring finger. This nerve is a terminal branch of the ulnar nerve. This flap is used to provide needed sensibility to the thumb and index finger pads. Its vascularity is supplied by the corresponding proper digital artery with venous return through multiple adventitial venae comitantes. The flap can be pedicled all the way to the superficial palmar arch by ligating the proper digital artery to the radial aspect of the small finger, creating a flap with adequate reach to resurface the volar aspect of the thumb. Adequate blood flow in the radial digital artery of the ring finger and ulnar digital artery of the small finger must be ensured prior to flap transfer. The common digital nerve to the fourth web space can be divided along the fascicles to allow for mobilization of the digital nerve to the level of the superficial arch.
This patient has third-degree burns of the thumb with destruction of the digital nerves resulting from an electrocution injury. In order to restore function and sensibility in the thumb, the neurosensory flap is elevated from the ulnar aspect of the ring finger, tunneled across the palm of the hand subcutaneously, and inset into the perimeter of the thumb wound to provide sensation to the thumb pad.
Flap vascularity is not supplied by the dorsal metacarpal artery or posterior interosseous artery. Nor do the radial and median nerves innervate the ulnar aspect of the ring finger, which would be transposed to provide sensation to the thumb pad.
A 10-year-old boy who underwent surgical repair of near-complete avulsion of the fingertip dorsally at the level of the mid nail bed 8 months ago is evaluated because of hook-nail deformity of the long finger. Which of the following structures is most likely to be deficient when considered for surgical reconstruction?
A) Distal tuft
B) Germinal matrix
C) Sterile matrix
D) Volar epidermis
E) Volar pulp
The correct response is Option A.
Hook-nail deformity is a volar curvature of the nail that occurs because of lack of bony support to the sterile matrix. Hook-nails most commonly occur after trauma. The best means of prevention is ensuring that the distal limit of sterile matrix is a minimum of 2 mm proximal to the distal phalanx tip. Reconstruction includes grafting, local and regional flaps, and distal flaps. Bone grafting (free, vascularized or phalanx osteotomy) is another option. Bone grafting has the highest failure rate due to reabsorption. Free vascularized nail flaps, arterialized venous nail flaps, and osteo-onychocutaneous nail flaps are another option.
A 55-year-old man comes to the emergency department because of a saw injury to the thumb. Physical examination shows a 3 × 2-cm soft-tissue defect from the interphalangeal crease to the tip of the right volar thumb with exposed bone and tendon. Which of the following is the most appropriate management?
A ) Amputation at the interphalangeal joint
B ) First dorsal metacarpal artery flap coverage
C ) Free great toe pulp transfer
D ) Split-thickness skin grafting
E ) Spontaneous healing
The correct response is Option B.
The thumb tip is an important structure for opposition and holding objects to the fingers. Thumb function depends on restoration of sensation and durable, reliable padding. When there is bone or tendon exposure, coverage with a flap is preferred. Small thumb tip defects (1 to 1.5 cm) can be reconstructed with a volar rectangular advancement flap, popularized by Moberg. Larger thumb tip defects require other flaps, such as the first dorsal metacarpal artery (FDMA) flap or the Little flap (dorsoulnar aspect of long finger). The FDMA flap can provide a larger wide flap than the Little flap and can be harvested with both venae comitantes and additional subcutaneous vein to provide more reliable venous drainage than the Little flap. Also, the FDMA flap donor site carries less risk of functional compromise of the donor finger than the Little flap donor site. The Little flap donor site can develop flexion contracture if the flap is harvested too volar over the finger, the interphalangeal creases are not preserved, and full-thickness skin grafting is not used on the donor. Both flaps are innervated and sensate and will require cortical reorientation, which can take approximately 1 year, more reliably for younger patients. Free toe pulp transfer would be excessive for this magnitude of injury.
When no bone or tendon is exposed, the defect can be reconstructed with a skin graft if greater than 1 cm or allowed to heal spontaneously if less than 1 cm.
A 12-year-old boy is brought to the emergency department because of persistent pain and bruising under the fingernail of his left index finger 6 hours after sustaining a crush injury. Physical examination shows a subungual hematoma that is contained to a portion distal to the lunula. The surrounding nail plate is adherent and intact. The nail plate is not torn or lifted. Which of the following is the most appropriate management?
A) Amputation
B) Digital block with epinephrine
C) Elevation
D) Nail plate removal and sterile matrix graft
E) Trephination
The correct response is Option E.
The treatment of nail injuries can vary depending upon whether or not a nail plate injury is noted. When the nail plate is intact, the diagnosis of a nail bed injury is determined by the presence of a subungual hematoma. Subungual hematomas cause pressure in the closed space between the nail plate and nail bed, resulting frequently in throbbing pain. Hematoma drainage (trephination) is required for pain relief. This can be done with a battery-powered microcautery device or heated sterile paper clip. The hole should be large enough to allow for prolonged drainage. Care should be taken with the cautery device to avoid further injury to the nail bed.
If the nail edges are disrupted or the nail plate is torn, the nail plate should be removed to explore and repair the nail bed. The torn nail plate can be removed to provide exposure for the repair. Lifting the nail plate can sometimes further injure the nail bed. Complete removal is not always mandatory.
Extremity elevation will only alleviate the pain minimally. A digital block with epinephrine will provide temporary relief. Amputation is excessive treatment for a nail bed hematoma.
Nail beds that are missing a sterile matrix can be reconstructed with a sterile matrix graft, often from the same injured nail bed (smaller defect) or the great toe (larger defect).
A 22-year-old woman has the split nail deformity shown in the photograph above. On physical examination, the deformity involves the sterile and germinal matrices. The patient does not want to lose the nail. Which of the following is the most appropriate management?
(A) Excision of the scar and primary closure of the nail bed
(B) Split nail grafting from the same nail bed
(C) Split nail grafting from the toe
(D) Full-thickness nail grafting from the finger
(E) Full-thickness nail grafting from the toe
The correct response is Option E.
In this patient who has a split nail deformity, the most appropriate management is full-thickness nail grafting from the toe. This deformity is caused by injury to the nail bed, leading to scarring of the bed. The nail plate does not grow in the scarred area, resulting in a split in the nail plate.
Because the deformity involves both the sterile and germinal matrices, only a full-thickness nail will provide the sterile and germinal matrix components required for reconstruction. Harvest of a full-thickness nail produces a significant cosmetic defect at the donor site; therefore, a graft from the second toe is thought to provide the least unsightly result.
In patients who have a small scar affecting the sterile matrix only, appropriate management may include excision of the scar and re-approximation of the sterile matrix; however, the sterile matrix is not usually mobilized and re-approximated unless the affected area is narrow. In addition, the germinal matrix cannot tolerate re-approximation.
As mentioned above, a split nail graft from either the same nail bed or another nail bed will not provide the components needed for reconstruction of this defect. In addition, using another finger as a donor will result in an unsightly donor defect in the hand.
Following split-thickness skin grafting, which of the following dressings can be used at the donor site to minimize discomfort, reduce the risk for infection, and decrease healing time?
(A) Bismuth tribromophenate-impregnated gauze (Xeroform)
(B) Heterograft
(C) Hydrocolloid polymer complex (DuoDerm)
(D) Silicone membrane-nylon fabric composite (Biobrane)
(E) o-Tolylazo-_-naphthol- (Scarlet Red-) impregnated gauze
The correct response is Option C.
An occlusive dressing consisting of a polyurethane foam and a hydrocolloid polymer complex (DuoDerm), or a semiocclusive dressing consisting of synthetic adhesive moisture vapor permeable films (eg, Op-Site, Tegaderm) will minimize patient discomfort, reduce the risk for infection, and decrease healing time.
Fine mesh gauzes (eg, Scarlet Red, Vaseline, Xeroform) use the semiopen technique of wound healing. Epithelialization and infection rates are favorable, but, when compared with other dressings, pain and discomfort are greater.
Another version of the semiopen wound-healing technique involves the use of a semipermeable silicone membrane and a knitted nylon fabric covalently bonded to porcine collagen (Biobrane). This method is more comfortable for the patient but is associated with a higher rate of infection following skin grafting.
Biologic dressings (eg, cadaveric skin homografts, heterografts, porcine xenografts, amniotic membranes) are frequently associated with marked inflammation of the wound, delayed epithelialization, and prolonged wound healing times.
During coverage of a defect with a reverse cross-finger flap, which of the following is the most appropriate location for application of a full-thickness skin graft?
A ) Dorsal surface of the middle phalanx of the donor finger
B ) Dorsal surface of the middle phalanx of the recipient finger
C ) Volar surface of the distal phalanx of the donor finger
D ) Volar surface of the distal phalanx of the recipient finger
E ) Volar surface of the middle phalanx of the donor finger
The correct response is Option B.
Multiple local flaps are available for coverage of finger defects. A reverse cross-finger flap is used to cover soft-tissue defects on the dorsum of an adjacent digit. The skin on the donor finger is incised on the side closest to the recipient finger and elevated off of the underlying dorsal subcutaneous tissue. The dorsal subcutaneous tissue of the donor finger is raised as a flap based on the side closest to the recipient finger. The flap is sutured to the recipient finger and is used as a bed to receive a full-thickness skin graft. The native skin is then returned to the dorsum of the middle phalanx of the donor finger. If the volar surface of a finger requires coverage, a standard (not reverse) cross-finger flap is used.
The photograph shown on the left demonstrates the reverse cross-finger flap raised from the dorsum of the long finger and positioned over the index finger. After inset of the flap, the skin of
the donor finger is closed primarily. A skin graft is applied over the flap on the dorsum of the recipient finger as shown in the photograph on the right.
A 45-year-old man who sustained a crush injury to the right index finger when a 55-gallon drum fell on the finger eight days ago. On examination, there is significant compromise of the soft tissues and multiple stellate pattern injuries of the volar and ulnar aspects of the finger with marginal necrosis. There are gangrenous changes of the fingertip and only marginal vascularization of the finger to the level of the proximal interphalangeal (PIP) joint. The dense anesthesia in the distribution of the radial and ulnar digital nerves has worsened over time. The flexor and extensor tendons are intact. Radiographs show several areas of impacted debris; there is no evidence of fracture.
Which of the following is the most appropriate management?
(A) Healing by second intention
(B) Debridement and dressing changes
(C) Amputation at the PIP joint
(D) Amputation at the metacarpophalangeal joint
(E) Ray amputation
The correct response is Option E.
This 45-year-old man sustained a multilevel crush injury to his right index finger, resulting in gangrenous changes at the level of the midportion of the midphalanx. In most patients who have extensive soft-tissue and nerve damage, the affected digit should be shortened to a level at which ample soft tissue is available for primary closure of the wound. However, complete ray amputation is recommended instead in this patient because the soft-tissue injuries extend proximal to the level of the distal interphalangeal joint. This single-stage procedure will securely close the soft tissues, allowing the patient to return to work sooner. In addition, oblique osteotomy should be performed through the proximal
metacarpal flare, enhancing the curved web space. Hand function can be realized by allowing the middle finger to perform as an index finger during grasping.
Healing by second intention is typically reserved for fingertip amputations without exposed bone. In this patient who has an extensive area of injury with contamination, second intention healing may result in the development of wound sepsis. Although dressing changes can aid in wound debridement, they would be inadequate in a patient with a severely injured and possibly contaminated digit.
Staged reconstruction of the skin, tendons, nerves, and vessels would result in a stiff, insensitive digit that would be bypassed during hand activities.
Amputation at the PIP joint is rarely indicated for the index finger. Amputation through the metacarpophalangeal joint would result in a prominent, cumbersome amputation stump and would provide no advantage over ray amputation because the intrinsic and extrinsic tendons have already been sacrificed.
A 30-year-old man comes to the emergency department 30 minutes after he sustained traumatic avulsion amputation of the thumb at the level of the interphalangeal joint. The amputated digit was wrapped in a wet towel immediately after the injury and has been kept on ice since that time. Physical examination shows complete avulsions of the extensor pollicis longus and flexor pollicis longus tendons from their muscle bellies. Which of the following is the most appropriate management of this patient’s injury?
A) Replantation and tendon repair
B) Replantation of the amputated digit and immediate fusion of the interphalangeal joint
C) Revision amputation and delayed pollicization
D) Revision amputation and subsequent transfer of the great toe
E) Revision amputation, immediate shortening of the bone, and closure of the skin
Correct answer is B.
Because the extensor pollicis longus (EPL) and flexor pollicis longus (FPL) tendons are avulsed, repair or reconstruction of their function is difficult. When these tendons are reinserted, there is a risk of infection. The main contribution of the thumb to overall hand function is through its length and ability to oppose the fingers to grab and hold objects. The critical length of the thumb is the level of the interphalangeal (IP) joint. It is optimal to preserve the length of the thumb to at least the IP level. Thumb length is more important than motion. Considerable motion can be preserved through the metacarpophalangeal and carpometacarpal joints of the thumb. Therefore, thumb function is not significantly altered with fusion of the IP joint. Furthermore, fusion of the IP joint can allow for less tension across the microneurovascular repairs. This has been shown to improve survival rates for thumb replantations as well as produce reliable recovery of two-point discrimination through nerve repairs that are not under tension. Furthermore, shortening of the thumb allows for avoidance of the potential need for grafts to repair the artery or nerves. If the IP joint of the thumb is fused, there is no need to repair the FPL tendon. Revision amputation with closure, pollicization, or toe transfer would not yield the functional outcome of a successful replantation. Specifically, transfer of the great toe is not needed if thumb length is at the IP level.
A 55-year-old man who is a woodworker is brought to the emergency department 45 minutes after completely severing the thumb of the nondominant left hand just distal to the interphalangeal joint while using a table saw. The amputated digit was wrapped in a moist gauze towel immediately after the injury. The patient smokes one pack of cigarettes daily. Physical examination shows a clean cut through the thumb with minimal tissue loss. Which of the following is the most appropriate management?
A) Replantation of the thumb
B) Great toe transfer
C) Moberg advancement flap
D) Revision amputation
E) Split-thickness skin graft
An amputated thumb is an indication for replantation in the hands of an experienced microsurgeon with the appropriate team regardless of the level of injury to the thumb. In the scenario described, the thumb is well preserved and the cut is clean with no avulsion injury. Attempts should be made to preserve the length and function of the thumb with replantation.
Immediate pollicization of the great toe is not indicated in the scenario described, where the distal amputated thumb is well preserved and available for replantation. If the amputated part had been mangled, lost, or inappropriately preserved, thumb reconstruction with great toe transfer could be offered as a reconstructive option.
The importance of the thumb in hand function precludes any further amputation of the thumb. Although the thumb wound would likely close by secondary intention if there is no exposed bone, it is best to preserve as much length as possible, making replantation the operation of choice for the thumb.
If the part is not replantable, the volar advancement flap, or Moberg flap, is indicated for preservation of length and soft-tissue coverage of exposed bone. A split-thickness skin graft could potentially also be used for coverage but would require shortening of the exposed bone and would not provide the sensibility that is helpful in the use of the thumb. Reconstruction of the thumb does not offer restoration of length and is not appropriate in this clinical situation.
A 65-year-old man who plays golf three times weekly has severe Dupuytren contracture of the small finger of the dominant right hand. The dense cord extends along the ulnar aspect of the hand and digit. The contracture of the metacarpophalangeal joint is 60 degrees, and the contracture of the proximal interphalangeal joint is 95 degrees. Which of the following is the most likely origin of the ulnar cord?
(A) Abductor digiti minimi
(B) Abductor pollicis brevis
(C) Antebrachial fascia
(D) Cleland ligament
(E) Volar carpal ligament
The correct response is Option A.
In the small finger, the ulnar cord typically originates from the musculotendinous junction of the abductor digiti minimi. From this location, the pretendinous band, spiral band, lateral digital sheath, and Grayson ligament can become involved, which can result in significant contractures at the metacarpophalangeal and proximal interphalangeal joints.
The other structures listed are not typically involved in Dupuytren contracture. The abductor pollicis brevis is the most radial thenar muscle and does not affect the ulnar cord. The antebrachial fascia is the superficial forearm fascia and is not related to Dupuytren contracture. The contractile cords involve Grayson ligaments and not Cleland ligaments. The Cleland ligament is dorsal to the neurovascular bundle. The volar carpal ligament covers the Guyon canal.
A 35-year-old man comes to the emergency department immediately after sustaining degloving avulsion of his dominant right ring finger. The avulsed finger tissue has been wrapped in a towel and packed in ice since the injury occurred. Physical examination shows complete degloving of the soft tissue of the ring finger, including both neurovascular bundles, from the level of the metacarpophalangeal joint distally. The flexor and extensor tendons and the joints are intact. Which of the following interventions is the most appropriate management?
(A) Amputation of the finger with primary closure
(B) Burial of the skeletal structures in an abdominal skin pocket
(C) Reconstruction of the finger with an abdominal flap
(D) Reconstruction of the finger with a free wraparound flap from the great toe
(E) Reconstruction of the finger with a neurosensory island flap
The correct response is Option A.
Ring avulsion injuries have been classified as follows:
Class I: Circulation adequate; standard bone and soft-tissue treatment is indicated
Class II: Circulation inadequate; vessel repair is required for viability
Class III: Complete degloving or amputation is required
This patient has sustained a complete degloving avulsion, which qualifies as a Class III injury. Although management of ring avulsion injuries remains controversial, the recommended approach for these severe injuries is completion of the amputation.
Burial of the finger’s skeletal structures into an abdominal pocket does nothing toward constructing a functional finger.
Class I injuries, which have adequate circulation, and Class II injuries, which have inadequate circulation, can be reconstructed successfully in most cases. Reconstruction of these less severe injuries can be effected by various microsurgical procedures and skin flap reconstructions.
This patient underwent shortening and closure of the amputation stump. He was able to return to his vocation as a mechanic approximately two weeks after the original injury.
A 45-year-old carpenter presents with a six-month history of an ulceration of the ring fingertip and pain at rest. Digital brachial index is 0.45, and angiography demonstrates occlusion of the ulnar artery. The patient has tried three months of calcium channel blockers and aspirin without relief. Which of the following is the most appropriate treatment for this patient?
A) Amputation of the fingertip
B) Chemical sympathectomy
C) Reconstruction of the ulnar artery
D) Stellate ganglion block
E) Surgical sympathectomy
The correct response is Option C.
Conservative treatment includes smoking cessation, calcium channel blockers, anticoagulation therapy, stellate ganglion block, and behavior modification. Nonoperative management is generally considered first-line treatment, because most patients will have at least partial resolution of their symptoms. With that said, 70% of those treated nonoperatively had partial resolution of their symptoms, and only 12% had complete resolution. Of patients treated operatively, 42% had complete resolution of their symptoms and 42% had partial resolution.
For patients with evidence of more advanced disease such as digital ulceration, chronic resting pain, or conservative management failure, operative intervention may be considered. Preoperative noninvasive vascular studies can be used to determine which patients may require reconstruction versus simple excision and ligation. Studies have suggested that a digital brachial index less than 0.7 indicates reconstruction may be warranted. An index of less than 0.5 suggests critical ischemia, which may result in tissue loss.
Surgical options fall into two basic groups: resection of the involved arterial segment with ligation, and vascular reconstruction with or without interposed graft. Graft occlusion is reported in as high as 78% of patients. Despite a high percentage of occlusion, patients remained satisfied. Patients with occluded reconstructions did not experience worsening of symptoms in comparison with the patent reconstructions. Preoperative digital brachial index values, although informative as to the patient’s digital perfusion, do not mandate a particular operative intervention. The general treatment algorithm is to perform surgery on patients who have failed on medical management and local treatment to heal any digital soft tissues. A decision on ligation versus reconstruction can be made with the assistance of information gathered by preoperative angiography and noninvasive vascular studies, as well as intraoperative assessment of ulnar digital perfusion with temporary occlusion of the ulnar artery. Poor perfusion following temporary occlusion mandates reconstruction of the artery, whereas adequate perfusion, despite occlusion, can be treated with simple excision or ligation of the diseased ulnar artery segment
A 37-year-old woman is brought to the operating room after sustaining a crush injury to the left upper arm during a rollover motor vehicle collision that included prolonged extraction from the vehicle. In the operating room, the patient underwent bypass grafting to reconstruct the brachial artery after fixation of the humerus. Postoperatively, the patient reports increasing pain of the left forearm with increasing pain control requirement. Doppler shows intact radial and ulnar pulses. Which of the following clinical studies is most likely to help determine the treatment plan at this time?
A) Assessment of capillary refill of the finger tips
B) Doppler examination of the digital arteries
C) Duplex scan to check patency of graft
D) Measurement of the compartment pressures of the forearm
E) Pulse oximetry of the digits
The correct response is Option D.
In this scenario, the physician should rule out compartment syndrome for several reasons: the crush injury, the reperfusion state, and pain unrelieved by pain medications prior to providing more pain relief. Pain that is out of proportion to the expected level or out of proportion to examination findings should alert the clinician to the possibility of compartment syndrome.
The only study option provided that would give the clinician the ability to rule out compartment syndrome is the direct measurement of compartment pressures, which is recommended by several authors. Loss of peripheral artery pulses or perfusion to the distal skin would be very late presentations of the ischemic process, at a point where intervention, such as fasciotomy may not be effective. Missing this diagnosis in a patient such as this one, may lead to loss of muscular function (ischemic muscle contracture) even if the limb as a whole is salvaged.
The presence of palpable pulses is reassuring evidence for the patency of the bypass graft but does not tell the clinician about the perfusion in the capillary beds of the muscle. Similarly, perfusion of the skin and the digits does not guarantee flow in the muscle that was reperfused.
A 22-year-old man comes to the emergency department 30 minutes after he sustained an amputation injury to the tip of the little finger of the left hand while using a circular saw. The patient was unable to locate the amputated part. Physical examination shows amputation of the tip of the finger at a level distal to the insertion of the profundus. The distal phalanx is exposed and protruding. Which of the following surgical interventions is most appropriate to preserve the grip strength of the hand?
A) Excision of the profundus tendon
B) Healing by secondary intention
C) Local flap coverage
D) Revision to the middle phalanx head
E) Suturing of the profundus tendon to the extensor tendon
The correct response is Option C.
Local flap coverage is indicated when there is exposed bone or tendon. The flexor profundus tendon attaches to the base of the distal phalanx. Loss of the profundus tendon results in a significant loss of grip strength. Therefore, the profundus should be preserved if possible. Wounds on the fingertip that are smaller than 1 cm are allowed to heal by secondary intention, which provides better return of sensation and an even smaller scarred area. Larger areas, particularly those with an exposed distal phalanx, require coverage. Skin grafting may be indicated for large wounds that are not expected to heal in a reasonable amount of time. The profundus tendon should not be sutured to the extensor tendon, because this could result in a quadriga effect and a loss of grip strength.
A 60-year-old mechanic is brought to the emergency department 12 hours after sustaining a amputation of the nondominant left thumb at the level of the metacarpophalangeal joint. At the time of injury, the amputated part was immediately placed in a plastic bag over an ice slush. He underwent arthroplasty of the carpometacarpal joint of the left hand five years ago.
Which of the following factors is most likely to influence the success of replantation in this patient?
(A) Age of the patient
(B) Hematocrit of the patient
(C) Length of ischemia time
(D) Mechanism of injury
(E) Previous hand surgery
The correct response is Option D.
In addition to the experience of the surgeon, the mechanism of injury is most likely to influence the success of replantation in any patient who has sustained an amputation of a digit. Because the vessels of the amputated part are damaged in patients who sustain avulsion and crush amputations, perfusion will be impeded, decreasing the likelihood of successful replantation. In addition, cooling of the amputated part contributes to the success of the replantation, as the amputated part can be replanted as late as 24 hours after injury if it is well preserved.
The age of the patient does not affect the success rate of replantation in the absence of other comorbid conditions or a history of cigarette smoking. Likewise, hematocrit and a history of hand surgery generally do not influence the outcome of replantation significantly. Because digits do not contain muscle, the length of ischemia time is not an influential factor.
A 16-year-old boy presents with clubbing of all digits of both hands. Medical history includes cyanotic congenital heart disease. Which of the following is the most likely cause of the abnormal appearance of the nail in this patient?
A) Hypertrophy of the distal phalanx
B) Hypertrophy of nail keratin
C) Increased vascular connective tissue
D) Reduction of collagen in the distal finger
E) Tenosynovial hypertrophy
The correct response is Option C.
Digital clubbing has been recognized since 400 BC. It is associated with numerous systemic disorders including cardiac, pulmonary, malignant, thyroid, and gastrointestinal conditions, as well as autosomal dominant hypertrophic osteoarthropathy in healthy individuals.
Characteristic findings include the profile sign or Lovibond angle (the nail makes a greater than 180-degree angle as it exits the eponychial fold) and an increase in the distal phalangeal to interphalangeal depth ratio.
The complete pathophysiology is not fully understood. However, theories include abnormal arteriovenous anastomoses, growth hormone abnormalities, and megakaryocyte production of platelet-derived growth factor. Whatever the mechanism, sampling of the tissues demonstrates an increase in vascular connective tissue, causing the appearance.
Although nail shape is altered, this is unrelated to nail keratin deposition. With long-standing clubbing, collagen is deposited in the digit and likely is irreversible. Clubbing is associated with increased blood flow except in familial cases. The tenosynovium is not part of clubbing. The distal phalanx bone is unaltered in clubbing.
A 25-year-old man is brought to the emergency department because of a sharp traumatic amputation at the mid-humerus level. The intact amputated part is placed in a plastic bag. The patient is brought to the operating room for attempted replantation with a warm ischemia time of 4 hours. He is hemodynamically stable. Which of the following is the most appropriate next step in management?
A) Arterial repair to restore inflow
B) Arterial shunt to restore inflow
C) Bone fixation
D) Bone shortening
E) Revision amputation and immediate targeted muscle reinnervation
The correct response is Option B.
Upper limb amputations proximal to the wrist tolerate a maximum warm ischemia time of 4 to 6 hours due to the large muscle mass. Beyond this time, muscles start undergoing irreversible myonecrosis. In this patient, with a warm ischemia time at the upper limit tolerable, the most urgent order of business is to restore perfusion. This can rapidly be achieved with a temporary shunt placed from the proximal arterial stump to the arterial stump in the amputated part. This maneuver will result in bleeding from the unrepaired veins, and therefore the patient will need a transfusion. This venous egress also drains the lactic acid out of the body, thus preventing cardiovascular collapse due to metabolic acidosis. Bone shortening should then be performed so that healthy vessels and nerves are obtained for anastomosis. Rigid bone fixation is then performed. Tendons and muscles are then repaired. Vascular repair is then performed between healthy vessel ends, preferably primarily but with vein grafts if needed. Nerve repair is then performed between healthy nerve ends. If a large segment of nerve is damaged due to severe soft tissue loss, the nerve ends are tagged for future repair after the soft tissue has stabilized. Replantation should be attempted if patient hemodynamics and medical conditions permit. Although the incidence of postoperative pain in replanted patients is 39 to 79%, the functional outcome of a replanted upper extremity is better than an amputation. Furthermore, several studies have demonstrated higher patient satisfaction with replantation than with prosthesis. Amputation with targeted muscle reinnervation is not appropriate at this initial stage since replantation for limb salvage is a viable option in this case.
A 65-year-old man comes to the office because of difficulty grasping items with the left hand. He sustained a sharp amputation of the thumb in the distal third of the proximal phalanx 9 months ago. Palmar and radial abduction of the residual thumb is symmetric to the uninjured thumb. Photographs are shown. Which of the following procedures is most likely to improve hand function in this patient?
A) Four-flap Z-plasty of the first web space
B) Groin flap
C) Heterodigital island flap augmentation of the thumb
D) Pollicization of the index finger
E) Resection of the first dorsal interosseous muscle
The correct response is Option A.
When approaching post-traumatic thumb reconstruction, two of the most important factors in determining treatment are the residual length and relative function of the remaining thumb. In this patient with a distal amputation and good active range of motion, the simplest and most beneficial procedure would be web-space deepening via a four-flap Z-plasty. Simple Z-plasty and dorsal rotational flaps can also serve to deepen the first web, but the most commonly used technique is the four-flap Z-plasty.
Groin flap can address soft-tissue defecits that this patient does not have.
Instances involving contractures of the first web space frequently require release or resection of some of the first web musculature, including the first dorsal interosseous. In a supple thumb with good abduction, this would not be necessary.
Pollicization of the index finger or the stump of an index finger can be useful when amputation occurs in the proximal third of the thumb. In the setting of a healthy index finger, however, amputations through the metacarpal would likely be best handled via toe-to-thumb transplantation.
Heterodigital island flaps are one method of restoring glabrous, sensate skin to the palmar surface of the thumb. Such flaps were useful primarily when trying to restore sensation to a thumb reconstructed through osteoplastic techniques. This flap would not add length to the thumb or serve to deepen the web space.
Six months after sustaining a traumatic amputation of the right index finger at the level of the distal interphalangeal joint, a 27-year-old machinist has extension of the proximal interphalangeal joint of the index finger when he attempts to make a fist. Revision amputation and primary closure were performed at the time of the initial injury, and the patient has undergone occupational therapy for the past six months.
Which of the following is the most appropriate management?
(A) Osteotomy of the middle phalanx
(B) Release of the sagittal bands
(C) Sectioning of the lumbrical muscle
(D) Tenolysis of the profundus tendon
(E) Transfer of the interosseous muscle
The correct response is Option C.
In this 27-year-old machinist who has a lumbrical-plus deformity secondary to release of the flexor digitorum profundus tendon to the index finger, the most appropriate management is sectioning or division of the lumbrical muscle. Because the profundus tendon to the index finger is independent, proximal retraction causes proximal retraction of lumbrical tendon, leading to increased tension. With attempted flexion of the proximal interphalangeal (PIP) joint (ie, to make a full fist), the lumbrical muscle migrates more proximally, exerting tension on the extensor mechanism through the lateral band. Paradoxical extension of the interphalangeal joints results. Sectioning of the muscle can be performed as an outpatient procedure using a local anesthetic.
Osteotomy of the middle phalanx will not correct the muscle-tendon imbalance. Release of the sagittal bands is most likely to result in subluxation of the extensor tendons across the metacarpophalangeal joint. Tenolysis of the profundus tendon is appropriate for management of flexion contractures with adhesions, and transfer of the interosseous muscle is performed for correction of ulnar drift in patients with rheumatoid arthritis.
A 25-year-old police officer is brought to the emergency department 30 minutes after he sustained amputation injuries to the dominant right hand. Physical examination shows guillotine-type amputation of the thumb at the level of the metacarpophalangeal (MP) joint and index finger at the proximal interphalangeal (PIP) joint. The amputated parts were wrapped in moist gauze and placed in a plastic bag immediately after the injury. Transfer of the patient to a replantation facility will not be possible for at least 18 to 24 hours because a hurricane in the region has disabled all ground and air emergency transport. The emergency department physician has experience suturing minor lacerations of the hand but has no microscopic surgical experience. He contacts the replantation facility by telephone for consultation with a plastic surgeon. Which of the following is the most appropriate instruction regarding management of the patient’s condition until transport to a replantation facility is possible?
A) Debride and close the wounds
B) Dermabrade the epidermis of the amputated parts and insert them under the skin of the abdomen through two separate incisions
C) Reattach the amputated parts with sutures as a composite graft and apply splints to the involved digits
D) Replant the amputated parts with step-by-step guidance of the plastic surgeon via telephone
E) Wrap the amputated parts in saline-soaked gauze and place them in a plastic bag on a bed of ice
Correct answer is E.
The time interval between amputation and replantation can change a replantable situation to an unreplantable one. There are no strict guidelines for ischemia times. There have been case reports of a successful hand replantation performed after 54 hours of cold ischemia and a successful digit replantation after 42 hours of warm ischemia. Acceptable ischemia time is dependent on the amount of muscle in the amputated part: the more muscle, the shorter the acceptable ischemia time. General guidelines are that if warm ischemia time is greater than 6 hours for amputations proximal to the carpus or 12 hours for the digits, replantation is usually not recommended. Cold ischemia can double these acceptable time limitations. The patient discussed is a young police officer with an amputation of the thumb and index finger. The thumb is the only opposable digit and, as such, is critical for hand function. Thumb amputation is a strong indication for replantation. The dangerous weather in the scenario described precludes quick transfer; however, the cold ischemia time would be approximately 24 hours in a digit with no muscle. This time frame is within the limits for a successful outcome. Therefore, the most appropriate management in the scenario described is to wrap the amputated parts in saline soaked gauze and place them on ice. Debriding and closing the wounds is not appropriate because this would treat the cold ischemia time as a contraindication for replantation and commit this patient to late reconstruction. Reattaching the amputated parts with sutures as a composite graft and applying splints to the involved digits is not appropriate because of the size of the amputated digit. Small composite grafts can survive; however, this applies to young children with distal tip amputations. Furthermore, suturing the parts back on will create a condition of warm ischemia instead of cold ischemia. In situations of near-complete amputations, the attached digits can be placed in ice/saline slurry. Dermabrading the epidermis of the amputated parts and inserting them under the skin of the abdomen through two separate incisions will not work for similar reasons. Replanting the amputated parts with step-by-step guidance of the plastic surgeon via telephone is inappropriate because of the poor outcome associated with an inexperienced operator.
A 55-year-old man is evaluated 10 days after sustaining a traumatic amputation of the tip of the right index finger. A photograph of the debridement is shown. X-ray study shows no fractures. After debridement of loose eschar, no bone or tendon was exposed. The wound is approximately 1 cm2. Which of the following is the most appropriate treatment of the resulting defect?
A ) Coverage with bilateral V-Y flaps
B ) Coverage with volar advancement flap
C ) Dressing changes
D ) Periarterial sympathectomy
E ) Split-thickness skin grafting
The correct response is Option C.
Although composite grafts will often survive in children and may be attempted in adults, aggressive defatting of the amputated segment and removal of bone fragments may still fail.
The photograph demonstrates an eschar resulting from necrosis following reattachment of an amputated fingertip pulp. In the absence of underlying exposed ?white? structures such as joints, or tendon denuded of tenosynovium, optimal healing and function will occur via secondary intention. In this case, removal of any sloughing eschar will facilitate local wound care during healing.
Skin grafting is useful for covering larger defects; however, sensation over the graft will be less satisfactory than over a fingertip wound that heals by secondary intention.
A variety of local flaps have been used for fingertip tissue loss, including bilateral V-Y (Kutler) and volar advancement (Atasoy/Tranquilli-Leali) flaps. V-Y flaps place a scar directly in the midline of the pulp and are limited in the degree to which they may be advanced. The longer volar advancement flaps may be useful in covering bone or supporting the nail bed in the setting of a palmar oblique amputation through the distal phalanx; however, these flaps carry an increased risk of flexion contracture at the proximal interphalangeal (PIP) joint.
Pulp necrosis can occur in the setting of digital ischemia due to Raynaud disease or thrombotic ulnar artery occlusion (hypothenar hammer syndrome). Periarterial sympathectomy can prevent tissue loss in some cases of vascular spasm or insufficiency. In this patient with an otherwise visibly well-perfused hand and discrete history of trauma, digital ischemia would be an unlikely cause of the necrosis.
A 50-year-old man has a thumb tip defect measuring 5.5 _ 2.5 cm with exposed bone at the base of the wound. Which of the following is the most appropriate management of this defect?
(A) First dorsal metacarpal artery flap
(B) Littler neurovascular island flap
(C) Moberg flap
(D) Revision amputation
(E) Skin graft
The correct response is Option A.
Because thumb length is critical to hand function, including opposition of the thumb to the fingers, defects of the thumb tip should be managed conservatively. Shortening and/or revision amputation should be avoided if possible.
Of the two flaps used for thumb reconstruction, the first dorsal metacarpal artery flap is preferred over the Littler neurovascular island flap because a large vein can be included with the venae comitantes. There is decreased morbidity at the donor site, and the prospects for cortical reorientation of sensation on the thumb are better. Young patients can relearn to interpret pressure on the thumb flap as the thumb and not as the original long finger donor.
This patient’s defect is too large for a Moberg flap. The exposed bone might impede proper healing of a skin graft.
A 48-year-old woman is referred to the office by her primary care physician for evaluation of a painless ulcer on the tip of the index finger of the right hand that has been present for the past three months. Medical history includes scleroderma with thin, tight, fibrotic skin on the face and perioral region. On physical examination, dry eschar and visible bone are noted at the tip of the index finger. The skin of the other digits is thin and shiny. No flexion contractures of the interphalangeal joints are noted. Radiographs of the index finger show mild resorption of the tuft. Which of the following is the most appropriate management at this time?
(A) Amputation of the distal phalanx and direct closure of the stump at the level of the distal interphalangeal joint
(B) Conservative debridement of the soft tissue of the tip of the finger and resection of exposed bone
(C) Ray amputation of the digit and primary closure
(D) Resection of the distal phalanx to the level of the distal interphalangeal joint and soft-tissue healing by secondary intention
(E) Urgent digital sympathectomy and debridement of eschar
The correct response is Option B.
Scleroderma is an autoimmune disease that includes a disorder of the connective tissue and small blood vessels. This disease can affect the skin, hands, gastrointestinal tract, heart, lungs, and kidneys. The sclerosis or fibrosis is commonly seen in the skin of the face and perioral area. This sclerosis of the face gives the patient a mask-type appearance characteristic of scleroderma. The CREST symptom complex has been used to describe the most common findings of systemic sclerosis: calcinosis, Raynaud phenomenon, esophageal dysfunction, sclerodactyly, and telangiectasia. Ulceration at the fingertips is a common finding secondary to poor circulation. Skin breakdown can also occur at the proximal interphalangeal (PIP) and metacarpophalangeal (MP) joints caused by bony joint deformities as well as poor circulation.
Tip ulcerations are common because of the poor circulation associated with scleroderma. Many of these ulcerations will successfully heal over time without surgery. An initial conservative approach should therefore be taken. This approach includes conservative debridement, topical antibiotics (eg, silver sulfadiazine), and limited resection of exposed bone. If active infection is present, antibiotics should be administered.
If ulceration and pain fail to respond to conservative treatment, more aggressive intervention is required, including amputation and possible digital sympathectomy. Unfortunately, many patients who undergo digital sympathectomy continue to have pain and suffer recurrent ulceration.
Calcinosis is the deposition of calcium within the dermis or subcutaneously. These deposits can cause pain, spontaneously cause skin breakdown, and drain calcific material. Symptomatic lesions require excision or partial removal to alleviate symptoms.
Amputation, digital sympathectomy, and resection of the distal phalanx with secondary healing are not appropriate because conservative therapy should be attempted first.
A 38-year-old man sustains a third-degree burn to the left hand. On examination, there is a 2 ( 2-cm area of exposed extensor pollicis longus tendon at the interphalangeal joint with destruction of the paratenon. Which of the following is most appropriate for coverage of the wound?
(A) Split-thickness skin graft
(B) Full-thickness skin graft
(C) Kite flap
(D) Moberg flap
(E) Thenar flap
The correct response is Option C.
The patient has a burn wound with exposed tendon (no paratenon) over a joint. Appropriate coverage will permit tendon glide and joint motion. Sensation is not required. The kite flap can be based on the first or second dorsal metacarpal artery over the dorsal aspect of the index and long fingers, respectively. The flap territory includes the dorsal skin of the proximal phalanx of the index finger for the first metacarpal artery flap and the dorsal skin of the proximal phalanx of the long finger for the second metacarpal artery flap. The radial and dorsal proximal interphalangeal sensory branches can be used to create a sensate flap. The first dorsal metacarpal artery flap works well when used for coverage of dorsal thumb wounds; however, the second dorsal metacarpal artery flap will not reach the dorsal thumb.
Coverage of this patient’s wound with a skin graft will be unsuccessful. Neither a split- nor a full-thickness graft will heal over exposed tendon without paratenon, which will not provide adequate vascularization to support a skin graft. Additionally, the graft would adhere to the tendon.
A Moberg flap advances volar tissue from the thumb pad 1 to 1.5 cm for volar pad coverage. A thenar flap is appropriate for index and long fingertip pad defects. The thenar flap will not reach the interphalangeal joint area of the dorsal thumb.
A 60-year-old man is referred for evaluation of a flexion deformity of the left long finger. Physical examination shows a thickened cord from the mid palm to the volar proximal phalanx of the long finger. The metacarpophalangeal joint cannot be extended beyond 30 degrees. A photograph is shown. Which of the following cells is most directly responsible for the contraction of the cord shown?
A) Macrophage
B) Merkel cell
C) Myofibroblast
D) Stem cell
E) Striated myocyte
The correct response is Option C.
Myofibroblasts act on the collagen bundles deposited by fibroblasts to cause alignment into a cord and shortening of the cord. These cells also secrete extracellular matrix components that remodel in a shorter configuration, creating durability of the contracture. More mature cords are believed to be less cellular.
Macrophages are believed to act on the extracellular matrix but do not produce contracture. Striated myocytes are in skeletal muscle and are not involved in Dupuytren disease. Merkel cells are a sensory end-organ and are not involved in Dupuytren disease. Stem cells including adipocyte progenitors are known to exist in Dupuytren cords. They are hypothesized to develop into cells that affect the cord. There is no evidence that these cells act on Dupuytren cords while they are still stem cells.
An 18-year-old woman sustains injuries to the dominant right hand during a motor vehicle collision. Examination shows multiple lacerations to the long finger and traumatic amputation of the index finger with a 2 x 1-cm loss of the volar pad and exposure of bone and the flexor digitorum profundus tendon. The proximal half of the nail is intact. After repair of the lacerations of the long finger, which of the following is the most appropriate management of the injuries to the index finger?
(A) Reverse cross-finger flap
(B) Revision amputation
(C) Secondary healing
(D) Thenar flap
(E) V-Y advancement flap
The correct response is Option D.
The thenar flap is ideal for young patients with a volar defect of the index or long finger. These patients are not likely to have stiffness, and the radial digits are in proximity to the volar metacarpophalangeal joint of the thumb.
A reverse cross-finger flap is used to cover dorsal defects on adjacent digits. In this patient, a cross-finger flap is not an option because of the lacerations to the long finger.
Revision amputation is an option, but in this young woman it is preferable to preserve the nail and finger length for functional and cosmetic reasons.
Healing by secondary intention is not appropriate for patients with injuries involving exposed bone and tendon. Secondary healing is ideal for young patients but is usually reserved for smaller defects.
A V-Y advancement flap is indicated for distal tip amputations, but it is not an option in this patient because there is significant volar loss at the insertion site of the flexor digitorum profundus tendon on the proximal base of the distal phalanx. V-Y advancement flaps can be designed volarly or laterally. The volar flap is most useful when the volar skin is longer than the dorsal skin. The lateral flaps are designed bilaterally over the midlateral line and advanced to the tip, leaving a longitudinal incision at the tip of the digit.
A 44-year-old man comes to the emergency department immediately after he sustained an injury to the tip of the left thumb while working with a table saw. Physical examination shows a 1.5 × 1.5-cm wound involving the volar tip of the thumb with bone visible within the base of the wound. Which of the following is the most appropriate management?
(A) Cross-finger flap
(B) Island Moberg flap
(C) Secondary healing
(D) Skin grafting
(E) Thenar flap
The correct response is Option B.
The Moberg flap is the most effective intervention for thumb tip defects of 1.5 cm or smaller. Some of the tactics that have been described to facilitate distal advancement of the flap include flexion of the thumb interphalangeal crease, extension of the lateral incisions proximal to the metaphalangeal crease, and islandization of the flap by releasing the skin at the base of the flap and skin grafting the donor wound.
The cross-finger flap can be used for the thumb but is best suited for fingers of younger patients because of the risk of flexion contractures when used in older patients. Secondary healing is inappropriate in the case described because of the large size of the wound. Skin grafting is not appropriate for the patient described because bone is exposed. The thenar flap is harvested from the thumb and, therefore, is not used to reconstruct the thumb.
A 25-year-old woman comes to the emergency department for replantation of the left ring finger three hours after sustaining type III avulsion of the digit. Which of the following factors is most significant in ensuring success of the replantation effort?
(A) Leech application after replantation
(B) Long finger ulnar digital artery–based revascularization
(C) Native digital artery anastomosis
(D) Systemic heparinization
(E) Three-hour ischemic time
The correct response is Option B.
In patients with type III avulsion injury of the ring finger, the soft-tissue envelope detaches completely from the base of the finger. The zone of injury is extensive and the extent of arterial vessel injury cannot be determined, even with microscopy.
Recent technical modifications have focused on revascularizing the amputated digit as distally as possible to bypass the injured arterial segments. Effective techniques include long vein grafting or transfer of the ulnar digital artery from the long finger to anastomose the digital artery at the level of the distal interphalangeal joint. The transposition technique appears to be simpler because it affords exact matching of luminal diameters and involves only one anastomosis. Although amputation for type III avulsion injury has been advocated in the past, recent research has shown that judicious replantation efforts may achieve a better functional and aesthetic outcome.
Replantation requires recreation of arterial flow. Due to the extent of injury to the native arteries, an arterial source is required from an adjacent digit, i.e., the long finger ulnar digital artery. A native artery inflow source would thrombose due to the intimal injury. Leech application is useful for inadequate venous outflow. Successful arterial inflow, not systemic heparinization or relatively short ischemic time, is critical for success of replantation.
A 67-year-old farmer sustains an amputation of the volar soft tissue of the thumb. Physical examination shows a 2 * 1.5-cm defect with loss of 50% of the tactile surface of the thumb. There is exposure of 0.5 cm of the distal phalanx. Which of the following is the most appropriate management?
(A) Healing by second intention
(B) Full-thickness skin grafting
(C) Coverage with a Moberg flap
(D) Coverage with a neurovascular island flap from the long finger
(E) Second toe pulp transfer
The correct response is Option C.
The most appropriate management is coverage with a palmar advancement flap, also known as a Moberg flap. This flap provides durable and sensate skin to the pulp of the thumb and preserves length. Although it can be used to cover defects as large as 2 * 2 cm, it is more typically used for defects that have a length of 1 to 1.5 cm. Flap transfer involves mobilization of both digital arteries and nerves and advancement of volar skin, resulting in a minimal flexion deformity.
Healing by second intention is contraindicated in a patient who has a defect involving exposed bone.
Full-thickness skin grafts can be used for reconstruction of small defects but would result in an insensate thumb. In addition, grafting over exposed bone does not provide adequate coverage for pinch functions.
Although transfer of pulp from the second toe may be indicated for thumb reconstruction, it is not the procedure of choice in a 67-year-old farmer.
Coverage with a neurovascular island skin flap derived from the long finger is appropriate for reconstruction of large defects that involve sensate pinch on the radial aspect of the thumb. This technique is often performed secondarily if other first-line methods fail to restore satisfactory sensation.
A 50-year-old man comes to the emergency department after sustaining amputation of the right long finger involving an avulsion mechanism. The patient is taken to surgery for replantation. During surgery, extensive vascular injury is seen, and an approximately 2-cm vascular gap of the digital arteries and veins results following excision of injured vessels. Which of the following interventions is most likely to increase the probability of functional digit replantation?
A) Bone shortening
B) Medicinal leech therapy
C) Postoperative warming
D) Systemic heparin
E) Vein grafts
The correct response is Option E.
In patients who sustain digital amputation as a result of an avulsion mechanism, there is often an extensive zone of injury that precludes primary vascular anastomosis. Vein grafts permit vascular anastomosis outside of the zone of injury.
Bone shortening can sometimes allow excision of the injured vasculature and primary anastomosis. However, in this case, bone shortening is unlikely to make up for a 2-cm vascular gap.
Longer vascular gaps can be addressed with vein grafts. Despite the fact that vein grafts involve an additional anastomosis per vessel compared to primary anastomosis, they have been found to exhibit similar rates of thrombosis and replantation survival.
Medicinal leech therapy can help address venous congestion, but is typically considered when venous congestion occurs after attempt at surgical replantation, or if no suitable veins can be found for anastomosis.
While postoperative warming and systemic heparin are often used adjunctively in patients undergoing replantation, they have not been demonstrated to increase the likelihood of survival of the replanted part, and would most likely not have as significant an effect as restoring perfusion to the amputated part using vein grafts.
A 30-year-old man with a history of radius and ulna midshaft fractures underwent fasciotomies for acute compartment syndrome of the nondominant left volar forearm with immediate return of normal perfusion 4 months ago. He is now pain-free with normal sensation but has persistent stiffness and weakness of the fingers, despite appropriate splinting and physiotherapy. His compartments are soft, and there are no joint contractures. He has full motion and normal strength, except the fingers and thumb can fully extend only with the wrist flexed, and finger and thumb flexion have MRC grade 4/5 strength. Which of the following is the most appropriate next step in management?
A) Dynamic splinting
B) Flexor tendon transfers
C) Intrinsic releases
D) Selective muscle origin slide
E) Strengthening physiotherapy
The correct response is Option D.
The patient is presenting with evidence of Volkmann ischemic contracture of his deep volar forearm compartment musculature, specifically flexor digitorum profundus and flexor pollicis longus. Flexor digitorum superficialis could be minimally involved, but the wrist flexors are spared. Mild median nerve involvement with full recovery and sparing of the ulnar nerve would support this diagnosis. The patient has already undergone appropriate physiotherapy. With persistent findings at 4 months, the most appropriate treatment is surgical exploration, debridement of necrotic muscle, with either selective muscle origin slide or tendon lengthening of preserved but contracted muscle.
Although continued dynamic physiotherapy could potentially provide further improvement in this patient’s muscle tightness, strengthening physiotherapy will not address the problem adequately. Dynamic splinting could complement physiotherapy and be helpful but has likely provided most of its benefit in the 4 months after initial surgery. Intrinsic releases would be indicated in intrinsic muscle contractures; however, this patient has involvement of the extrinsic flexors, not the intrinsic muscles. Finally, flexor tendon transfers would be indicated for more severe cases of Volkmann contractures, where there is no muscle function remaining. This patient’s examination suggests adequate muscle function remains.
A 54-year-old man comes to the office because he has a two-year history of difficulty straightening the small finger of the dominant right hand. He reports that the finger catches when he puts on gloves or reaches into his pockets. He has no history of serious illness. Physical examination shows firm cords extending along the palmar surface of the small finger axis and the ulnar border of the proximal phalanx. Flexion contracture of the metacarpophalangeal (MCP) joint is 30 degrees, and flexion contracture of the proximal interphalangeal (PIP) joint is 65 degrees. Palmar/digital fasciectomy with complete correction of the PIP joint contracture is planned. Which of the following best describes the long-term outcome of both joints?
MCP PIP
(A) Good Good
(B) Good Poor
(C) Poor Good
(D) Poor Poor
The correct response is Option B.
Treatment of the PIP joint flexion contracture in Dupuytren disease can be difficult and often unsatisfying because early (within one to three years) partial recurrence is common. Adding to this frustration is the failure of recurrent PIP joint disease to respond to therapy and splinting as effectively as MCP joint recurrences.
Primary treatment of PIP joint Dupuytren contractures often results in incomplete correction; this also stands in contrast to the complete correction typically obtained at the MCP joint.
Recurrent PIP joint disease may require more aggressive management, including more extensive joint release (accessory collateral ligaments, palmar plate/check rein ligaments, flexor sheath) and possible dermatofasciectomy with full thickness skin graft reconstruction. Outcomes from reoperation are guarded, and arthrodesis of the PIP joint as a salvage procedure may be warranted.
Routine release of the volar/palmar plate has not been shown to improve outcomes for primary correction of PIP joint contractures in Dupuytren disease.
A 42-year-old man sustains an avulsion injury to the index finger of the left hand after it is caught in a piece of machinery. He says he needs to return to his job as a manual laborer as soon as possible. The bone of the proximal phalanx is exposed. The avulsed segment of the finger includes the distal and middle phalanges and soft tissue to the level of the mid-proximal phalanx, along with segments of tendons, nerves, and vessels. Which of the following is the most appropriate management?
A ) Coverage with a groin flap
B ) Coverage with a reverse radial forearm flap
C ) Microvascular replantation
D ) Revision amputation
E ) Skin grafting
The correct response is Option D.
The most appropriate management is revision amputation.
For the patient described, the tendons, nerves, and vessels have been stretched and avulsed, which results in an extensive zone of injury.
A well-planned amputation should be considered a reconstructive procedure and can return functional use of the hand to the patient. Goals include preservation of functional length, provision of durable coverage, preservation of sensibility, prevention of neuromas, prevention of joint contractures, minimal morbidity, early prosthetic fitting, and early return to activities of daily living. The surgeon should take into account the patient €™s occupation, functional status, and attitude toward the proposed amputation. In the scenario described involving a proximal phalanx amputation of the index finger in a manual laborer, the shortened finger will likely be bypassed in favor of the long finger for use in pinch. Amputation can result in a reliable and functional outcome and allow the patient to return to work quickly. Completion of the amputation can be performed, or ray amputation can be undertaken, to eliminate the intervening index finger segment and improve thumb pinch function.
A groin flap can be used for soft-tissue coverage but requires the hand to be attached to the groin for a period of time. This can result in stiffness of the other digits and requires a staged procedure.
A reverse radial forearm flap can be used for coverage of soft-tissue defects in the hand. This requires sacrifice of a major vessel to the hand and, in this case, would only preserve a section of bone that will serve little function.
Microvascular replantation is a challenging prospect in the setting of a ring avulsion injury. Relative contraindications in the patient described would include the avulsion nature of the injury and presence of single-digit amputation within Zone 2. These factors lead to less successful outcome, and replantation would delay the return to work.
Skin grafting is not likely to be successful in this patient, who has exposed bone. The lack of tendons would result in absence of movement, and the lack of nerves would lead to loss of sensibility.
A 45-year-old woman with systemic sclerosis (scleroderma) has severe Raynaud phenomenon. A photograph is shown. Periarterial injection of botulinum toxin type A is being considered for treatment in this patient. This treatment is believed to relieve vasospasm in Raynaud phenomenon by which of the following mechanisms?
A) Blocking fast sodium channels in axonal gap junctions
B) Increasing the activity of chronically down-regulated group C nerve fiber nociceptors
C) Inhibiting Rho/Rho kinase activity
D) Obstructing myofibroblast contractile activity in vascular smooth muscle
E) Promoting substance P secretion/receptor sensitivity
The correct response is Option C.
Several mechanisms have been proposed to explain the effect of botulinum toxin type A (Botox) to inhibit Raynaud phenomenon in patients with scleroderma. Studies have demonstrated inhibition of Rho/Rho kinase activity, inhibition of substance P secretion and receptor sensitivity, and decreasing the activity of chronically up-regulated C-fiber nociceptors all to occur in models of Raynaud phenomenon that responded to Botox treatment. Fast sodium channels conduct axonal signals AT in gap junctions, but have not been shown to be affected by Botox. Myofibroblasts may be involved in late fibrosis of scleroderma patients but do not exist within the vascular smooth muscle.
A 40-year-old woman has an extravasation injury following a CT scan. An automated power injector was used to inject 100 mL of nonionic contrast medium into an intravenous cannula on the dorsum of the hand approximately 60 minutes ago. On examination, the hand appears edematous with mild erythema and is moderately tender. The skin is intact with no blistering. Capillary refill time is normal, and there is no neurologic deficit. Which of the following is the most appropriate next step in management?
A) Administration of a corticosteroid
B) Bedside exploration of the intravenous cannula site
C) Elevation of the extremity
D) Surgical exploration with dorsal fasciotomy and carpal tunnel release
E) Surgical exploration with dorsal fasciotomy only
The correct response is Option C.
In a patient with an intravenous extravasation, if the symptoms are mild (pain, swelling, or erythema), elevation and cold compresses will usually lead to complete resolution. Patients who have more severe symptoms, such as neurovascular compromise, may need additional evaluation of compartment pressures and potentially surgical exploration for decompression; however, the first step in treatment is still elevation of the extremity.
Extravasation injury was once a difficult problem. The extravasation of ionic contrast at high osmolality had increased risk for soft-tissue complications, and plastic surgery consultation was often necessary. The switch to nonionic, low-osmolality contrast over the past decade has resulted in a significant decrease in complications. In a recent study of 69,657 patients undergoing a CT scan, the rate of extravasation was 0.7% (476 patients), and only one patient required operative intervention and decompressive fasciotomy.
Corticosteroids do not have a role in extravasation injuries.
A 32-year-old man sustains an avulsion injury involving the volar soft tissue of the left thumb. Physical examination shows exposure of the flexor pollicis longus tendon. The first dorsal metacarpal artery flap is to be used for closure of the defect.
Which of the following best describes the location of the first dorsal metacarpal artery during flap harvest?
(A) Adjacent to the common digital artery to the thumb
(B) At the deep palmar arch
(C) Over the periosteum of the first metacarpal
(D) Within the fascia of the first dorsal interosseous muscle
(E) Within the subcutaneous tissue over the first dorsal interosseous muscle
The correct response is Option D.
The first dorsal metacarpal artery courses within the fascia of the first dorsal interosseous muscle; in rare cases, it may lie within the muscle itself. It communicates with the perforators from the superficial palmar arch at the level of the metacarpophalangeal joint.
The first dorsal metacarpal artery flap is axially patterned and based on a terminal branch of the radial artery after it exits the region known as the anatomic snuff box. This region is bordered volarly by the abductor pollicis longus (APL) and extensor pollicis brevis (EPB) tendons (first dorsal compartment) and dorsally by the extensor pollicis longus (EPL) tendon (third dorsal compartment). The skin paddle of this flap is obtained from the dorsal aspect of the index finger over the proximal phalanx, and the venae comitantes and superficial veins provide venous drainage.
A 28-year-old man is brought to the emergency department 30 minutes after he sustained avulsion injuries to the nondominant left hand when it became caught in a motor vehicle fanbelt. Physical examination shows amputation of the index finger at the level of the proximal interphalangeal joint as well as a 2 x 1-cm area of soft-tissue loss. Replantation of the amputated digit is performed, and the resulting 2 x 1-cm soft-tissue avulsion volar defect is covered with an arterialized venous flow-through flap with overlying skin interposed as a vein graft in the arterial repair. Which of the following is the most likely early complication of this flap procedure?
A) Arterial thrombosis
B) Congestion of the flap
C) Failure of the replantation
D) Hematoma from vessel leak
E) Loss of flap due to infection
Correct answer is B.
Venous flow-through flaps (VFTFs) are unusual but are gaining acceptance for certain kinds of hand and finger wounds. The ideal site for coverage with a VFTF is a long and narrow defect needing thin soft tissue. VFTFs typically become congested in the first week and then decongest over the following two weeks as they revascularize from the wound bed. VFTFs cannot reliably transfer composite tissue such as bone and tendon or cover a wide defect such as an entire palm. Because VFTFs do not bring in vascularization to the wound bed as well as classic flaps, they are not indicated in radiated or potentially infected wound beds. A small defect such as the 2-cm defect needing coverage during the replantation of the finger in the scenario described is the ideal candidate for this flap. When compared with simple vein grafts, VFTFs are not associated with increased rates of arterial thrombosis, failure of replantation, or hematoma. Although VFTFs are more susceptible to infection than typical flaps, congestion of the flap with superior epidermolysis is a much more likely complication.
A 5-year-old boy is brought to the emergency department after sustaining a crush injury to the index finger of his right dominant hand, resulting in amputation through the distal interphalangeal (DIP) joint. X-ray study shows a comminuted fracture of the proximal phalanx. Which of the following is the most significant CONTRAINDICATION to replantation in this patient?
A) Children have a difficult time adapting to functional deficits
B) The index finger is expendable
C) The mechanism and multiple-level nature of the injury preclude a functional result
D) Microvascular anastomosis is unlikely to be successful in a child of this age
E) Replantation will adversely affect epiphyseal growth
The correct response is Option C.
In the patient described, the most significant contraindication to replantation is the mechanism (crush injury) and multiple-level nature of the injury. It is highly unlikely that replantation will be successful with a crush mechanism due to the zone of injury. In addition, the multiple-level injury including the proximal phalanx and distal interphalangeal (DIP) joint precludes a functional result.
Replantation in children does not adversely affect epiphyseal growth. Children adapt quite well to functional deficits of the hand. Microvascular surgery in children, while challenging, has been shown to have a very high success rate when performed by skilled microsurgeons. The index finger can be considered expendable; however, children tend to have more favorable results than adults when it comes to replantation and, therefore, whenever feasible, replantation should be attempted, even if it is an isolated index finger injury. The mechanism of injury plays a greater role than the type of digit in determining the feasibility of replantation in the pediatric population.
A 64-year-old, left-hand–dominant man presents with Dupuytren contracture of the hand. Physical examination shows joint contractures of the small finger metacarpophalangeal (MCP) joint (35 degrees), proximal interphalangeal (PIP) joint (30 degrees); and ring finger MCP joint (30 degrees) and PIP joint (15 degrees). Needle aponeurotomy is planned to correct the deformity. Which of the following disease-related factors is most predictive of re-intervention following this procedure?
A) Dominant hand involvement
B) MCP contracture severity
C) Older age
D) PIP contracture severity
E) Presence of a natatory cord
The correct response is Option D.
The disease-related factor most strongly predictive of recurrence is the degree of PIP contracture. In a retrospective review of 848 interventions for Dupuytren contracture, authors noted that degree if PIP contracture and a younger age at time of initial intervention were most predictive of re-intervention. They looked at a cohort of 350 patients over an 11-year period in which multiple surgeons performed interventions for varying degrees of contracture of both the MCP and PIP joints. Comparisons between needle aponeurotomy, collagenase, and partial fasciectomy were performed. They reported 2-year re-intervention rates of 24%, 41%, and 4% respectively. Based on cumulative number of re-intervention, total direct surgical costs were $1,540, $5,952, and $5,507 respectively (Leafblad et al.). [1]
MCP contracture severity was not an independent predictor of re-intervention. Natatory cords are responsible for webspace contractures and do not independently result in MCP or PIP contractures. Younger age at time of initial intervention was predictive of re-intervention and older age was preventative. They found no differences in contracture re-intervention when comparing dominant to non-dominant hand.
In a prospective, randomized trial, investigators compared needle aponeurotomy to collagenase in patients with isolated PIP joint contracture. Patients were followed for 2 years following intervention. Primary outcome was reduction in contracture by at least 50%. At 2-year follow-up, 7% of collagenase patients had maintained improvement as compared to 29% of patients who underwent needle aponeurotomy, suggesting that collagenase treatment of Dupuytren disease leading to PIP contracture is not superior to needle aponeurotomy (Skov et al.). [2
A 25-year-old construction worker sustains a crush amputation involving the distal third of the dominant right thumb. Examination shows exposed bone at the distal phalanx. Which of the following is most appropriate for coverage of the wound?
(A) Split-thickness skin graft from the hypothenar region
(B) Full-thickness skin graft from the medial upper arm
(C) Cross-finger flap from the index finger
(D) Thenar flap
(E) Volar advancement flap
The correct response is Option E.
In this patient who has sustained a crush amputation of the distal third of the dominant thumb, the most appropriate management is coverage of the wound using a volar advancement, or Moberg, flap. This flap is most effective for coverage of thumb amputations that occur distal to the interphalangeal joint. It is comprised entirely of palmar thumb skin, providing an excellent color and tissue match. In addition, both neurovascular bundles are included for stable, sensate wound coverage.
Split-thickness skin grafting alone over exposed bone will result in a painful thumb due to inadequate padding. A full-thickness skin graft provides a poor skin match. Sensory recovery is diminished with the use of this type of graft. The cross-finger flap should not be used in construction workers or other patients who require good hand function following repair. In addition, a large donor site defect would result. A thenar flap, which is based on the thenar eminence, is used to cover adjacent defects and cannot be used for the thumb.
A 35-year-old woman is brought to the emergency department four hours after sustaining an amputation of the right thumb when it was caught in a machine at a meatpacking plant. The amputated part (shown) was wrapped in moist saline gauze and placed on ice within 20 minutes of the injury. Which of the following factors is most likely to limit the success of replantation of the thumb?
A ) Inadequate bone stock
B ) Initial treatment of digit
C ) Mechanism of injury
D ) Possibility of infection
E ) Warm ischemia time
The correct response is Option C.
The extensor tendons and flexor tendons in the scenario described have been avulsed from the musculotendinous junction. In addition, the nerve ends extend proximally beyond the level of the soft-tissue injury; both of these findings are indicative of an avulsion-type injury. Such injury mechanisms often result in significant intimal injury within digital arteries, limiting the success of replantation. The amputated part was appropriately managed, and warm ischemia time was minimized. Digits have been successfully replanted with greater than 24 hours of cold ischemia time. Amputations at the metacarpophalangeal or interphalangeal level of the thumb may result in joint fusion; however, in this scenario, bone stock is adequate for skeletal fixation. Infection is a potential problem following any traumatic hand injury, but adequate surgical debridement and appropriate antibiotic coverage make replantation loss from infection a rare occurrence.
A 55-year-old, right-hand–dominant man who is a machinist comes to the office because of inability to fully extend the right ring finger. Photographs are shown. The patient reports that his symptom began 5 years ago and has worsened progressively. Examination shows a 45-degree flexion contracture of the right ring finger (PIP) joint during attempts at full extension. All other joints demonstrate full extension, and the patient can create a complete fist during flexion. Regarding treatment options for this patient, which of the following interventions is most likely to provide the longest relief of his symptom prior to recurrence?
A) Collagenase injection and manipulation
B) Limited fasciectomy
C) Percutaneous aponeurotomy with lipografting
D) Percutaneous needle fasciotomy
E) Radiation therapy and splinting
The correct response is Option B.
Radiotherapy has been proposed as a potential treatment to slow or stop progression of Dupuytren contractures (palmar fibromatosis). A prospective study of radiotherapy revealed no greater efficacy than observation as an intervention for slowing the disease process. There is no evidence to suggest radiotherapy for correction of an established contracture.
Rijssen and colleagues established quantitative criteria for recurrence, using an increase of total passive flexion contracture of 30 or greater, compared to the 6-week follow-up values in previously treated joints. After 5 years, their recurrence rate following percutaneous needle fasciotomy was 85%; 21% for limited fasciectomy; and 32% of joints successfully treated with Clostridial collagenase. Percutaneous aponeurotomy with lipografting is an experimental technique which has shown some promise with correction of contractures and prevention of recurrence, but the evidence is level 4, with no controlled studies looking at this technique, in comparison to other established techniques.
Although limited fasciectomy provides the greatest degree of initial correction for Dupuytren contractures, as well as the longest period prior to recurrence, the costs associated with the procedure are by far the highest. When comparing the QALY costs of three interventions (limited fasciectomy, percutaneous needle fasciotomy, and collagenase injection), limited fasciectomy yielded the highest cost per QALY. The authors emphasize that this does not indicate limited fasciectomy is an inappropriate intervention—only that it is relatively the most expensive.
A 28-year-old man comes to the office 8 weeks after sustaining an amputation of the tip of the index finger that healed by secondary intention and has resulted in a hook nail deformity. Physical examination shows the residual nail growing over the residual tip of the finger. Which of the following is the most likely cause of this patient’s current condition?
A) Dorsal-sided tissue loss with loss of eponychial fold
B) Dorsal-sided tissue loss with loss of germinal matrix
C) Lateral-sided soft-tissue loss with ingrown nail fold
D) Volar-sided tissue loss with the nail bed folding over the residual tip
E) Volar-sided tissue loss with nail bed overgrowth by eponychial fold
The correct response is Option D.
The nail is supported by the dorsal tuft of the terminal phalanx. Following distal fingertip trauma, varying amounts of nail support may be lost, resulting in the nail curving palmarwards. This curvature is dependent on the degree of bony loss, the amount of remaining nail bed, and the degree of scar contracture at the hyponychial-pulp interface. The ?parrot beak,? or hook nail, deformity is caused most commonly by tight closure of a fingertip amputation and excessive palmar tension at the hyponychial-pulp suture line.
The hook nail deformity is a relatively common complication following fingertip amputation. It can be corrected or prevented with a carefully performed surgical procedure. The nail plate is removed. The redundant nail bed that is folded over the tip of the terminal phalanx is carefully removed with an additional 2 mm that is supported by the terminal phalanx, which ensures that wound healing will not draw the nail bed over the tip of the phalanx again. The fingertip is then resurfaced by a V-Y advancement flap, with precautions taken to avoid all tension in the flap.
A critically ill 85-year-old man requires arterial catheterization for serial arterial blood testing and continuous blood pressure monitoring. Which of the following is the most likely complication of brachial artery catheterization in this patient?
A) Increased risk of catheter thrombosis compared with radial artery catheterization
B) Increased risk of infection compared with femoral artery catheterization
C) Paresthesia to the radial three digits
D) Progressive clawing of the ring and little fingers
E) Transient loss of wrist and finger extension
The correct response is Option C.
Of the choices given, the most likely complication of brachial artery catheterization is paresthesia to the lateral three digits due to median nerve injury. The median nerve travels adjacent to the brachial artery along its length of the arm until the two separate deep to the bicipital aponeurosis and is thus subject to unintended injury in the course of attempted cannulation in the distal arm.
Progressive clawing of the ring and little fingers, and transient loss of wrist and finger extension, manifesting ulnar and high radial nerve injuries, respectively, have not been described as complications of brachial artery catheterization.
Common sites of arterial catheterization in adults include the radial, femoral, brachial, dorsalis pedis, and axillary arteries. Complications common to all sites include local and systemic infection, catheter thrombosis, bleeding, hematoma, and pain. One prospective cohort study involving almost 2500 patients found that femoral artery catheters were associated with increased incidence of both local infection and bloodstream infection when compared with radial arterial catheters. A significant relationship between other anatomical sites of arterial catheterization and increased incidence of infection has not been shown in other large studies.
There is a decreased risk of catheter thrombosis in larger caliber vessels like the brachial artery compared with smaller vessels such as the radial artery. Other risk factors for catheter thrombosis include duration of catheterization greater than 72 hours, larger gauge catheters, low blood flow states, peripheral artery disease, and vasospastic disorders.
A 25-year-old man sustained traumatic amputation of the nondominant index finger 3 hours ago and requests replantation. Which of the following factors has the greatest influence on survival of the injured digit after replantation?
A) Mechanism of injury
B) Number of vessels repaired
C) Patient’s smoking status
D) Time from injury to replantation
E) Use of anticoagulation
The correct response is Option A.
The mechanism of injury has the greatest influence on survival of replanted digits. Injuries from sharp devices that leave a clean cut with little or no crush component are the most amenable to replantation. The more the tissue is crushed or avulsed, resulting in greater vessel injury, the less likely the digit will survive. No studies have shown that the use of anticoagulants changes survival rates. Smoking decreases blood flow in digits, but has not been widely studied in replantation. Fingers have no muscle, which is the tissue most susceptible to ischemia, so digits can tolerate long delays as long as they are treated correctly. At least two veins per artery have been shown to help prevent venous congestion.
A 50-year-old man comes to the emergency department after sustaining an injury to the right thumb. A photograph is shown. The patient declines revision amputation and states that he does not want to lose thumb length or the nail. Which of the following is the most appropriate next step in management?
A) Complete the amputation of the thumb proximal to the germinal matrix
B) Obliterate the germinal matrix and remaining nail bed, followed by skin grafting
C) Transplant germinal matrix from the great toe
D) Transplant sterile matrix from the great toe
E) Continue to observe
The correct response is Option D.
The patient described has lost the sterile matrix of the nail bed. The germinal matrix is intact, as the nail continues to grow. The nail bed consists of the germinal matrix proximally and the sterile matrix distally. The sterile matrix allows the nail to adhere to the bed. Observation, amputation, and obliteration of the nail bed do not seem to be good options for a patient who has stated that appearance is paramount. The issue here is that the nail continues to grow, but cannot adhere to the full-thickness skin graft. The best option would be to harvest a split-thickness sterile matrix graft from the big toe. No additional germinal matrix is necessary as the germinal matrix is intact and producing nail.
A 45-year-old woman comes to the office because of a split in the nail plate following a previous crush injury to the left index finger. The patient desires improvement in the appearance of the nail. A photograph is shown. Which of the following is the most appropriate treatment?
A) Application of topical phenol
B) Excision/repair of the nail bed
C) Nail plate avulsion
D) Oral antifungal therapy
E) Split-thickness skin grafting
The correct response is Option B.
The most appropriate method of treatment is excision and repair of the nail bed.
The anatomy of the nail consists of a nail plate, nail fold, and a nail bed. The nail bed is the soft tissue beneath the nail plate, which is composed of the germinal matrix proximally and the sterile matrix distally. Most nail plate growth (90%) is provided by the germinal matrix. In cases of trauma, adherence between the nail fold dorsally and nail bed volarly can result in synechiae, interfering with nail growth and resulting in a longitudinal split in the nail. It is important to prevent adherence of dorsal and palmar elements by splinting the nail fold open during the healing phase. This can be accomplished by replacement of the nail plate if available, or using a piece of foil from the suture packet. This patient presents with a split nail deformity after previous trauma. There is scarring between the nail fold and the nail bed, resulting in a longitudinal split with inability to allow for growth of the nail plate in the central portion. Proper treatment consists of excision of the nail bed scar, with repair of the nail bed. Splinting of the nail fold during the healing period will prevent recurrent scarring of the dorsal fold to the palmar surface. In cases where there is significant scar tissue and inability to close the resultant defect after excision, grafting of the nail bed may be required. A split graft of the sterile matrix can be performed if the deficit is only present distally. If the germinal matrix is involved, a full-thickness graft is needed.
Avulsion of the nail plate alone will not eliminate the scarring at the proximal nail fold.
Oral antifungal therapy is useful in treatment of fungal onychomycosis.
Complete excision of the nail bed and split-thickness skin grafting can be used in nail ablation, but would result in absence of the nail and not yield a more cosmetic appearance.
Topical phenol application has been used for nail matricectomy, but can produce irregular tissue destruction and would result in loss of the nail.
A healthy, active 75-year-old man of Northern European descent comes to the office because he has had “tightness” in the ring and small fingers of the nondominant left hand for the past 15 years. He is able to work and play golf without difficulty. Physical examination shows a thick band of tissue in the palm extending into the involved digits. Fixed flexion deformities of 20 degrees in the metacarpophalangeal joints and no contractures in the proximal interphalangeal joints are noted. Which of the following is the most appropriate initial step in management?
(A) Observation
(B) Splinting
(C) Injection
(D) Fasciectomy
(E) Fasciotomy
The correct response is Option A.
Palmar bands in an older man of Northern European descent without a history of trauma is most likely Dupuytren’s disease. Because the patient is entirely functional and has a history of slow progression, observation would be the best course of management at this time. Threshold indications for surgery include a 30-degree contracture of the metacarpophalangeal joint or any contracture of the proximal interphalangeal joint. In a fully functioning patient with slow progression of disease, immediate surgery would not be necessary. Corticosteroid injections are useful for painful Dupuytren=s nodules but are generally ineffective for the extensive bands described. Finally, although therapy is a routine part of the postoperative management of this problem, it is unlikely to be of benefit in preventing the progression of disease. Stretching the joint contractures with splints and external fixators has shown limited long-term improvement.
Which of the following is the most commonly affected muscle in patients with Volkmann contracture?
A) Flexor carpi radialis
B) Flexor carpi ulnaris
C) Flexor digitorum profundus
D) Flexor digitorum superficialis
E) Pronator teres
The correct response is Option C.
Volkmann contracture results from ischemia and myonecrosis, which leads to secondary fibrosis of the muscles. The most frequently affected muscles are supplied by the anterior interosseus artery in the deep flexor compartment of the forearm—most commonly, the flexor digitorum profundus. Involvement is usually first seen in the ring and small fingers. With more significant ischemia, the flexor digitorum superficialis, flexor carpi ulnaris, flexor carpi radialis, and pronator teres muscles can also be affected.
A 28-year-old, right-hand–dominant woman is brought to the emergency department after sustaining a severe crush injury to the right upper extremity during a rollover motor vehicle collision. Examination shows multiple digit amputations and comminuted fractures of the distal radius and ulna. After multiple debridements, the limb is unsalvageable. Which of the following is the shortest stump length distal to the elbow that is required when fitting a prosthesis to maintain native elbow motion?
A) 3 cm
B) 8 cm
C) 13 cm
D) 18 cm
E) 23 cm
The correct response is Option B.
The minimum stump length required for prosthesis fitting is 5 to 10 cm distal to the elbow. Major upper extremity amputations are defined as amputations at or proximal to the wrist joint. Data from 2005 estimate that upper extremity amputations account for 34% of the 1.6 million people living in the US with limb loss, and 41,000 of these were considered major amputations. Limb salvage is always the goal of the initial surgical management; however, the decision to amputate is made when limb salvage will result in a less functional outcome for the patient.
The ideal stump has adequate length, durable soft tissue, minimal edema, and a tapered shape with minimal scar tissue that is not directly over the bony prominence. Muscle preservation is important for the potential use of a myoelectric prosthesis.
In order to preserve elbow function and allow for fitting of a prosthesis, at least 5 cm of a bony stump is required. Although shorter transradial stumps do not allow for pronation and supination, preservation of elbow function is felt to be worthwhile functionally. Transfer of the biceps tendon to the ulna should be considered in shorter transradial stumps to decrease the risk of developing a flexion contracture at the elbow.
Amputations at least 10 cm proximal to the wrist or at the junction of the middle and distal 1/3 are felt to be ideal in terms of muscle coverage, stability of prosthesis fit, and forearm rotation, but not required. More distal stumps can be problematic in terms of soft-tissue coverage over bone and limb-length discrepancy to accommodate the wrist unit of the prosthesis.
Replantation is most likely to be contraindicated in which of the following patients who have sustained amputations of a single digit at the level of the interphalangeal joint?
A ) A 5-year-old girl with an amputation through the index finger
B ) A 25-year-old steelworker with an amputation through the index finger
C ) A 30-year-old musician with an amputation through the long finger
D ) A 35-year-old attorney with an amputation through the long finger
E ) A 40-year-old construction worker with an amputation through the thumb
The correct response is Option B.
Functional outcomes following replantation vary with the level of injury. Replantation of single digits amputated within the zone II level is relatively contraindicated due to postoperative stiffness. It is also contraindicated when rehabilitation will significantly delay the patient €™s return to work and the procedure offers minimal or no functional benefit. Replantation of single digits, particularly index fingers, usually does not improve hand function.
Replantation should be considered on nearly all parts in healthy children. Replantation should be considered in most cases of thumb amputation.
A 28-year-old man is brought to the emergency department 3 hours after sustaining complete amputation at the level of the right mid forearm during a paper mill accident. A tourniquet was placed at the scene of the accident. He is medically stable and has no additional injuries. Which of the following is the most appropriate management of the amputated segment until vascular anastomoses are completed?
A) Clamp distal vessels
B) Cool amputated extremity
C) Flush artery with thrombolytics
D) Immerse in saline
E) Perform fasciotomies
The correct response is Option B.
The correct response is that the limb should be cooled until vascular anastomoses are complete.
Replantation of an amputated extremity remains the primary option at initial presentation. Contraindications for immediate replantation include an unstable patient who cannot tolerate a prolonged operative procedure, and patients in whom amputation and prosthesis would provide a better functional result than reconstruction. Warm ischemia should not exceed 6 hours, but can be extended to 10 to 12 hours when a part is cooled. Therefore, keeping a replanted part cooled until reperfused is important to success.
Clamping vessels in an amputated segment damages vessels needed for microanastomoses.
Cold heparinized saline and University of Wisconsin solution are commonly used to flush amputated parts to reduce thromboses and cool the part. Systemic complications are not common with the doses used. Persistent cold intolerance is a complaint of the majority of replanted patients. Unless thrombi are present, it is not routine to flush with thrombolytics. Immersing in saline is not appropriate.
When performing vascular anastomoses on larger masses of tissue with a longer ischemia time, performing arterial anastomoses and allowing run-off of metabolites through an open venous system before venous anastomoses are performed is recommended. Arterial perfusion may also be established early, allowing more time for repair of bone and tendon without prolonging ischemia times.
Fasciotomies are recommended as periods of ischemia can lead to compartment syndrome. However, these do not need to occur before anastomoses and should not delay reperfusion. Elevation of a replanted part is helpful to reduce post-operative edema but has no role before anastomoses.
A 40-year-old man comes to the office because of an 8-month history of intermittent ischemic change to the right ring finger. The patient reports intermittent coolness, pallor, pain, and cold sensitivity. Angiogram demonstrates a tortuous ulnar artery at the wrist and faint radial digital artery runoff into the right ring finger. Digital brachial index (DBI) of the ring finger is 0.9. Which of the following is the most appropriate first step in management?
A) Botulinum toxin type A injection
B) Excision and vein grafting of the ulnar artery
C) Ligation of the thrombosed ulnar artery segment
D) Thrombectomy and heparin drip
E) Trial of acetylsalicylic acid and nifedipine
The correct response is Option E.
This patient presents with hypothenar hammer syndrome. The gold standard for establishing the diagnosis is angiography. Aortic arch and upper extremity arteriography is the study of choice. In hypothenar hammer syndrome, the pathognomonic angiographic features can include tortuosity of the ulnar artery with a corkscrew appearance, aneurysm formation, occlusion of the ulnar artery segment overlying the hook of the hamate, occluded digital arteries in the ulnar artery distribution, and demonstration of intraluminal emboli at sites of digital obstruction.
Treatment depends largely on the severity of the ischemia. The therapeutic strategy is controversial because there are limited studies on this problem. For most patients with milder or transient/intermittent symptoms, nonsurgical treatment will be sufficient, particularly in the setting of vasospasm with adequate collateral circulation. Conservative nonoperative care may include smoking cessation, avoidance of further trauma (may require change of occupation), padded protective gloves, cold avoidance, calcium channel blockers (nifedipine, diltiazem), antiplatelet agents or anticoagulation, local care of fingers with necrosis, and pentoxifylline to reduce blood viscosity.
More severe symptoms (persistent ischemia, soft tissue loss/gangrene, ulnar nerve symptoms) or symptoms refractory to nonoperative management require consideration of surgical intervention. Surgical options in this setting include arterial ligation (assuming an intact radial/palmar arch), resection of thrombosed arterial segment or aneurysm with end-to-end anastomosis, or resection and vascular reconstruction with vein or artery graft. Some argue that best outcomes are seen in those treated with surgical resection and reconstruction. The benefits of surgical treatment include removal of the source of embolism, removal of the painful mass, relief of ulnar nerve compression, and creation of a local periarterial sympathectomy. As this patient has mild and intermittent symptoms without evidence of soft-tissue loss or gangrene or any evidence of ulnar nerve irritation, a trial medical management is indicated. Botulinum toxin type A is indicated for vasospasm secondary to Raynaud syndrome or disease and would not be part of the medical management algorithm.
A 32-year-old right-hand–dominant woman comes to the office because of an unstable nail at the mid-nail bed of the right ring finger. The nail sometimes comes off when she puts her hand in her pocket. History includes trauma to the nail bed of the ring finger. Physical examination shows full range of motion of the finger. X-ray studies show a bone exostosis dorsally. In addition to removal of the nail plate, which of the following is the most appropriate management of nonadherence of the nail?
A) Debridement of the distal phalanx exostosis
B) Debridement of exostosis and sterile matrix grafting
C) Nail bed ablation with split-thickness skin grafting
D) Reassurance that the nail will eventually regrow naturally
The correct response is Option B.
Nonadherence of the nail is the most common nail deformity after trauma and is usually distal to scarring in the nail bed or bone irregularities. The most common cause of nonadherence is nail bed scarring. The scar interrupts the progressive addition of nail cells from the sterile matrix to the volar nail plate, causing detachment of the nail. The nail is then unable to attach to the nail bed distally. Distal nonadherence of the nail may lead to subungual hygiene problems, an unstable nail when manipulating small objects or pain, when catching the nail on objects. Nonadherence is treated by removing the nail plate and excising the underlying scar. The area of scar resection can then be closed primarily or closed with a split-thickness sterile matrix graft if the defect is too large. Malalignment of distal phalanx fractures may cause or contribute to nonadherence. The exostosis should be removed to form a flat surface for the sterile matrix and subsequent nail adherence.
A 12-year-old boy has necrosis of the tip of the right small finger eight days after undergoing surgical release of a 90-degree flexion contracture of the proximal interphalangeal joint. The deformity resulted from a crush injury he sustained 10 years ago. In this patient, which of the following is the most likely cause of postoperative necrosis?
(A) Intra-arterial injection of anesthetic agent
(B) Laceration of the bilateral digital arteries
(C) Stretching of the digital arteries
(D) Tight splinting of the finger
(E) Vasospasm
The correct response is Option C.
When the proximal interphalangeal (PIP) joint is flexed for an extended period, the neurovascular bundles shorten. During contracture release, extension of the PIP joint must be performed judiciously. It may be necessary to accept a less-than-perfect PIP joint correction in an effort to prevent stretching of the digital arteries, which can cause insufficient perfusion distal to the PIP joint. After joint release and splinting, regular follow-up is necessary to ensure adequate perfusion. If vascularity is a concern, the surgeon must remove the splint and flex the finger to relax the digital arteries.
Vasospasm typically resolves and does not result in postoperative necrosis. Bilateral digital artery laceration loss would result in complete digital loss. Intra-arterial injection of a local anesthetic agent would not result in postoperative necrosis. A retained digital tourniquet, not a tight splint, would cause postoperative necrosis.
A 65-year-old man comes to the office because he has had worsening pain and stiffness in the right ring finger (shown) for the past five years. Which of the following additional findings will have the greatest impact on the decision to manage this patient’s condition surgically?
(A) Loss of flexion of the metacarpophalangeal joint
(B) Loss of flexion of the proximal interphalangeal joint
(C) Loss of extension of the metacarpophalangeal joint
(D) Loss of extension of the proximal interphalangeal joint
(E) Palmar nodule
The correct response is Option D.
This patient has a Dupuytren’s contracture of the hand. Dupuytren’s disease is a benign fibroproliferative disorder of the palmar fascia that may result in disabling finger contractures. This condition has been associated with epilepsy, alcoholism, chronic pulmonary disease, diabetes, and northern European ancestry. There is no cause-and-effect relationship between the existence of one of the comorbidities listed above and the development of Dupuytren’s disease.
Because the risk of complications with this disease is significant, there are narrow indications that must be met to justify surgery for this condition. The surgery involves direct excision of the involved fascia. This can be performed through zig-zag (Brunner), midlateral, Y-to-V incisions, and longitudinal with zig-zag rearrangement incisions. The complications of Dupuytren’s fasciectomy include recurrence, hematoma, skin loss, infection, nerve and arterial division, loss of flexion, reflex sympathetic dystrophy, and digital loss. Threshold indications concerning contractures are 30 degrees at the metacarpophalangeal (MP) joint and any at the interphalangeal (IP) joints, specifically the proximal interphalangeal (PIP) joint. Some studies have shown that when surgery was performed for patients with less than 30-degree MP joint contracture, surgery outcome was worse for some patients after fasciectomy. PIP joint contracture is not improved with joint release. Additionally, with or without PIP joint release, long-term improved motion is approximately 37% of the short-term improved motion.
The general indications for Dupuytren’s fasciectomy include loss of 30 degrees of MP joint extension, any loss of proximal phalangeal joint extension, and neurovascular compromise. Spiral cords can wrap around the neurovascular bundles and cause neurovascular compromise. Solitary asymptomatic palmar nodules are observed. Tender nodules can be injected with corticosteroids or collagenase. Pain in the hand is not an indication for Dupuytren’s surgery. The most commonly involved finger is the ring finger. The anatomic structures that are involved with Dupuytren’s include pretendinous bands, spiral bands, lateral digital sheet, Grayson’s ligament lateral digital sheet, and natatory ligament. The superficial transverse ligament, deep transverse ligaments, Cleland’s ligament, and Landsmeer’s ligament usually are not involved.
A 27-year-old man is brought to emergency department because of a thumb avulsion injury measuring 3 × 3 cm. A photograph is shown. Which of the following is the best option for sensate, soft-tissue coverage?
A) Cross-finger flap
B) First dorsal metacarpal artery flap
C) Moberg flap
D) Pedicled groin flap
E) Skin grafting
The correct response is Option B.
There are several sensate options for thumb pulp deformities. These include neurovascular island flaps, Moberg flaps, free toe pulp flaps, and the first dorsal metacarpal artery flap (FDMA). Cross finger flaps, skin grafts, and pedicle groin flaps do not have innate innervation. The defect in the question involves the entire pulp of the thumb overlying the distal phalanx and is too large for a Moberg advancement flap.
The FDMA flap is supplied by its eponymous artery, which travels in the fascia overlying the index metacarpal and supplies the skin overlying the dorsum of the proximal phalanx. The vessel is accompanied superficially by a branch of the radial nerve that provides neural activation to the skin overlying the proximal phalanx of the index finger. The flap can be transposed to provide sensate coverage of the tip of the thumb, and can provide sufficient size to resurface relatively large defects.
Cortical reorientation is the fact that the brain recognizes a stimulus from the flap area as a stimulus from the thumb, and not from the index finger. This process takes some time, but is usually complete after 2 years. Average static two-point discrimination in these flaps utilized for thumb resurfacing is 10 to 11 mm.
Use of the FDMA flap for resurfacing of the thumb pulp has been compared to heterodigital island flaps in several studies. Both remain options to be considered, but the ease of elevation, limited dissection, and acceptable donor site morbidity make the FDMA flap a common primary option for thumb tip resurfacing.
A 21-year-old man sustains traumatic amputation of the right thumb at the level of the metacarpal base. Pollicization should include osteosynthesis of which of the following?
A) Index metacarpal base to trapezium
B) Index metacarpal to thumb metacarpal
C) Index middle phalanx to thumb metacarpal
D) Index proximal phalanx to thumb metacarpal
E) Index proximal phalanx to trapezium
The correct response is Option D.
Transfer of the index finger to the thumb position on the hand (pollicization) typically transfers the proximal phalanx to the thumb metacarpal, as long as the base of the thumb metacarpal is preserved. Transfer of the middle phalanx or metacarpal of the index would create a neo-thumb that is too short or too large, respectively. Obliterating an intact carpometacarpal joint by transferring the index metacarpal to the trapezium would eliminate palmar and ulnar abduction of the thumb and compromise global hand function.
A 55-year-old woman comes to the office because of a 3-month history of severe pain and stiffness after undergoing tendon repair to correct a laceration to the extensor digitorum communis in Zone VI of the long finger of the nondominant hand. Which of the following additional clinical findings is most likely to support a diagnosis of complex regional pain syndrome?
A) Adhesion
B) Disrupted tendon repair
C) Normal blood flow
D) Numbness
E) Osteopenia
The correct response is Option E.
Osteopenia is related to disuse and is typical in Stage II of complex regional pain syndrome (CRPS). Calcium stores need to be depleted by 30 to 50% for the osteopenia to become apparent, so this finding may appear more regularly in postmenopausal women. The demineralization affects both cortical and cancellous bone.
The clinical presentation of CRPS is slightly different depending on the stage. In Stage I, there is extreme pain out of proportion to the injury, hyperesthesia, edema, erythema, and hyperhidrosis, all of which last for 3 months. Stage II is the ?dystrophic? phase and spans between the third and the ninth month. It is characterized by pain, pronounced stiffness, ?hard? edema, altered blood flow (increased warmth alternating with cyanosis), hair loss, decreased moisture, and osteopenia visible on plain x-ray study. Stage III starts at approximately the ninth month and lasts until 18 months after onset. It represents the ?atrophic? phase, which features increased stiffness and pale, cool, and dry skin, but decreased pain.
Tendon adhesions and disruption of the tendon repair are not unique features of CRPS and occur regardless as complications of tendon repair surgery.
Abnormalities in blood flow are common in CRPS, which is a direct effect of autonomic dysfunction, and occurs in 98% of cases. The vasomotor changes include loss of thermoregulatory and sudomotor control and manifest as a discolored limb (pale, red, or blue) with excessive sweating or anhidrosis.
Numbness is not a typical feature, whereas hyperalgesia and allodynia are very prominent and extend beyond the anatomical confines of any particular peripheral nerve. Exception would be noted if the inciting injury were to involve the nerve.
An 18-year-old man sustains a deep laceration to the volar aspect of the wrist. Multiple tendons are involved. Which of the following structures is located in the carpal tunnel?
(A) Abductor pollicis longus
(B) Flexor carpi radialis
(C) Flexor digitorum superficialis
(D) Palmaris brevis
(E) Pronator teres
The correct response is Option C.
The carpal canal contains nine tendons: the flexor pollicis longus and the four slips of both the flexor digitorum superficialis and the flexor digitorum profundus. The ulnar nerve is contained within Guyon’s canal, which is bordered by the pisiform ligament, hook of the hamate ligament, and pisohamate ligament. The flexor carpi ulnaris partly forms the volar boundary of Guyon’s canal. The flexor carpi radialis is contained within its own flexor sheath outside the carpal canal. The palmaris longus, which is also outside the carpal canal, continues into the palm as the palmar aponeurotic expansion. The brachioradialis is an accessory elbow flexor that crosses the elbow and inserts into the distal radial aspect of the radius. The pronator teres is the most superficial of the forearm muscles and inserts into the radius proximal to the level of the wrist. The abductor pollicis longus and extensor pollicis brevis are located within the first dorsal compartment. The lumbrical muscles arise from the flexor digitorum profundus tendons at the level of the palm and are typically distal to the carpal canal. The palmaris brevis is a vestigial muscle that partly constitutes the prominence of the proximal aspect of the hypothenar eminence of the hand. The palmar cutaneous branch exits from the median nerve at the level of the distal third of the forearm on the radial aspect of the flexor carpi radialis tendon as it travels toward the scaphoid tuberosity.
A 5-year-old girl sustains a stellate laceration of the sterile matrix of the nail bed of the left long finger when she closes a door on the finger. Which of the following is the most appropriate management?
(A) Allowing the nail bed to heal by second intention
(B) Primary repair of the nail bed
(C) Debridement of the nail bed and split-thickness skin grafting
(D) Debridement of the nail bed and split germinal matrix nail grafting
(E) Coverage of the nail bed with a free flap from the great toe
The correct response is Option B.
In this patient who has sustained a stellate laceration of the nail bed of the long finger, the most appropriate management is primary repair of the nail bed. Lacerations of the nail bed are common injuries that most frequently occur in the long finger, as it is typically the last digit to be moved during a situation of potential trauma to the hand. Injury to the nail bed can be classified as simple laceration, stellate laceration, avulsion, crush injury, or amputation.
The most appropriate management of simple and stellate lacerations of the sterile matrix is primary repair. These injuries are associated with the best prognosis; the nail typically has a normal appearance after healing.
In patients with avulsion and crush injuries, the outcome is often variable, as fracture of the distal phalanx may be associated. Any fracture that occurs must be reduced initially to eliminate irregular bone contours, which often result in a nail deformity. If there is contamination of the nail bed, the necrotic tissue is debrided. Split matrix grafting, using sterile grafts obtained from an adjacent portion of uninjured nail bed, can be performed for reconstruction. A split nail bed graft can be harvested also from the great toe.
Healing by second intention would result in deformity of the nail bed.
Germinal matrix grafts are appropriate for repair of trauma to the germinal matrix of the nail. These are full-thickness grafts that leave a deformity at the donor site following harvest.
Reconstruction of the nail bed with a free flap is reserved for management of chronic deformities of the nail and is not considered in patients with acute injuries.
A 5-year-old boy presents to the emergency department 4 hours after he sustained an amputation of his left index finger when it was slammed in a door. The parents brought the amputated digit in a plastic bag on ice. The amputation is at the level of the mid proximal phalanx. Which of the following is the most important reason to attempt replantation?
A) The amputation is proximal to the flexor digitorum superficialis insertion
B) The cold ischemia time is less than 6 hours
C) It is the index finger
D) It is a single-digit amputation
E) The patient is a child
The correct response is Option E.
Digital replantation should almost always be attempted in a child, except when the amputated part is severely crushed or there are other life-threatening injuries that preclude surgery. Replantation in children is technically more challenging due to the smaller size of the vessels. However, functional outcomes are more superior than in adults. The replanted parts have better sensory return and can have normal growth. Amputations through joints also exhibit remarkable joint remodeling.
A single digit amputation, especially proximal to the flexor digitorum superficialis (FDS) insertion is considered a contraindication to replantation. Digit replantations proximal to the FDS insertion have a poor range of motion as compared to amputations distal to the FDS insertion. This is, thus, an important landmark when making decisions about amputation versus replantation. Multiple digit amputations are an indication for replantation as the functioning deficit with loss of multiple digits is great. The thumb is responsible for 40% of the function of the hand and should always be replanted, if possible. Even if it is stiff and insensate, a replanted thumb will act as a post for opposition.
Index finger amputations at or proximal to the proximal interphalangeal joint are considered by many to be an indication for amputation. A stiff and painful index finger is likely to be excluded by the patient; amputation will result in better global hand function.
Digits tolerate longer ischemia times than more proximal level amputations, due to absence of muscle. Amputated digits tolerate warm ischemia times of 6 to 12 hours and cold ischemia times of 12 to 24 hours. Digital replantation has been reported with warm ischemia time of 33 hours and cold ischemia time of 94 hours. Cold ischemia time is thus not a major consideration in the decision-making process for amputation versus replantation.
A 32-year-old carpenter is scheduled to undergo a revision amputation procedure after sustaining an amputation of the left index finger at the level of the distal interphalangeal joint. She says that she often catches the finger on objects and has extension of the proximal interphalangeal (PIP) joint of the index finger when she attempts to make a fist.
Which of the following is the most likely cause of these findings?
(A) Adherence of the extensor tendon of the index finger
(B) Excessive power of the central slip over the flexor digitorum sublimis tendon
(C) Lumbrical plus deformity
(D) Quadriga effect
(E) Posttraumatic stiffness of the PIP joint
The correct response is Option C.
The findings in this patient are most likely caused by the development of a lumbrical plus deformity. Patients with this deformity have paradoxical extension of the proximal interphalangeal (PIP) joint during attempted flexion; the finger often catches on objects. Common causes of the lumbrical plus deformity include distal amputations, excessively long flexor digitorum profundus (FDP) tendon interposition grafts, and excessive FDP tendon lengthening procedures.
A patient with extrinsic extensor tendon adherence or scarring will have limited flexion across the metacarpophalangeal and PIP joints without paradoxical extension of the finger. The flexor digitorum sublimis tendon is still intact at the level of the distal interphalangeal joint. The quadriga effect results from adherence of the FDP tendon to the amputation stump. In patients with this condition, tethering of the FDP tendon in the injured finger leads to decreased motion and strength in the uninjured fingers. Posttraumatic stiffness would inhibit both passive and active range of motion of all joints in the hand.
A 35-year-old man is transferred to the emergency department via helicopter 7 hours after he sustained a table saw injury to the left hand. The patient smokes one pack of cigarettes daily. Physical examination shows amputation of the thumb and partial amputation of the index finger. No other injuries are noted. An x-ray and a photograph study are shown. Which of the following is the most appropriate management?
A) Replantation of the thumb and index finger segment
B) Revision amputation of the index finger and replantation of the thumb
C) Revision amputation of the thumb and index finger
D) Revision amputation of the thumb and microvascular “on-top plasty” of the index finger
E) Revision amputation of the thumb and pollicization of the index finger
The correct response is Option B.
In patients with traumatic amputations of the thumb, optimal reconstruction is provided by replantation. Vein grafts from the princeps pollicis artery, in the anatomical snuff box, are often required because of the difficult positioning. Vein grafts can be harvested from the foot or the forearm. For injuries at the metacarpophalangeal joint level, no reconstruction method approximates that of the replanted thumb. All efforts should be utilized in order to salvage the amputated thumb. In contrast, for index finger amputations, any surgery which would not provide normal or near normal function often only serves to hamper hand function. A traumatic injury which involved the index finger metacarpophalangeal (MCP) joint would require arthrodesis. A fused MCP joint would only get in the way and detract from function. Option (A) replantation of the thumb and index segment is not correct because of the decreased function which would be observed after a replantation of a poorly functioning index finger. Option (B) is the correct answer. Option (C) is incorrect and since it involved the amputation of both the thumb and index finger. Option (D) “on-top plasty” is a procedure which involves a non-vascularized bone graft covered with a local pedicle flap; this would not provide optimal function. Option (E), which is pollicization of the thumb to index finger, would be suboptimal. Pollicization would only be an option if the thumb were deemed unreplantable.
A 62-year-old man comes to the office 1 week after he sustained an avulsion injury to the soft tissue of the dorsal aspect of the left thumb while firing his crossbow. Moist dressing changes have not resulted in granulation tissue over the tendon. A photograph is shown. Which of the following is the most appropriate definitive treatment of the defect?
A) Alginate dressing changes
B) Cross-finger flap transfer
C) First dorsal metacarpal artery flap transfer
D) Full-thickness skin grafting
E) Split-thickness skin grafting
The correct response is Option C.
In this patient with exposed tendon denuded of tenosynovium (as evidenced by the photo and failure to granulate) flap coverage with the first dorsal metacarpal artery flap, or “kite” flap, will provide closure of the wound with similar skin to what has been lost with minimal morbidity. Apart from reaching the thumb dorsal surface, this flap has been successfully used to resurface palmar wounds of the thumb. Photographs of the flap are shown.
Alginate dressings would keep the wound moist but would not add to the conservative management of dressing changes the patient has already tried.
Skin-graft take relies on adequate granulation tissue in the recipient site to survive. Here neither split- nor full-thickness grafts would be likely to take. Furthermore, grafts directly to tenosynovium can limit tendon excursion after healing.
Cross-finger flaps are useful for resurfacing the palmar defects of adjacent digits. Reversed/turnover cross-finger flaps, or cross-finger fascial flaps, can resurface adjacent digits. Wound closure then requires skin grafting of the fascial flap at the recipient site.
A 37-year-old man who works as a laborer sustains a saw injury to the non-dominant left hand. X-ray studies are shown. Which of the following is the most appropriate functional option for reconstruction of this thumb defect?
A) Metacarpal lengthening
B) Osteoplastic reconstruction
C) Pollicization
D) Prosthesis
E) Toe transfer
The correct answer is Option C.
The x-ray study shows a carpometacarpal-level amputation of the thumb. Toe transfer, osteoplastic reconstruction, and metacarpal lengthening require part or most of the thumb metacarpal to be present. A thumb prosthesis would have limited functionality and be insensate.
Pollicization would potentially allow a sensate, functional index finger to accomplish some of the functions of the thumb. It is, however, not without its drawbacks because it is technically demanding and has a high likelihood of requiring secondary procedures. For a carpometacarpal-level amputation, pollicization provides the best option for function.
A 65-year-old man undergoes fasciectomy for Dupuytren disease affecting the left ring finger. During dissection, the ulnar digital nerve is noted to be centrally displaced on the ring finger by a Dupuytren cord. A photograph is shown. Which of the following palmar fascia structures contributes to the formation of this cord? A ) Central band
B ) Cleland ligament
C ) Lateral digital sheet
D ) Natatory ligament
E ) Septa of Legueu and Juvara
The correct response is Option C.
Except for Cleland ligament, any of the above named structures can become involved in Dupuytren contracture. Once involved in a contracture, the name of the structure is changed to include ?cord? (e.g., natatory ligament becomes natatory cord).
A spiral cord is formed when Dupuytren disease affects the pretendinous band, spiral band, lateral digital sheet, and Grayson ligament. The normal palmar fascia structures pass around the neurovascular bundle in a spiral fashion. As the cord forms and contracts, it eventually becomes straight. The neurovascular bundle is then displaced centrally on the digit and is distorted to spiral around the cord.
An 18-year-old man comes for evaluation 4 days after he sustained an avulsion injury of the pad of the index finger of his dominant right hand. A photograph is shown. The part was never recovered, and the patient has been performing dressing changes. The defect is 2.5 cm2 and extends to the distal phalanx bone. Coverage with which of the following flaps is most likely to result in fingertip sensation closest to pre-injury?
A) Cross-finger flap
B) First dorsal metacarpal artery flap
C) Homodigital island flap
D) Reverse radial forearm flap
E) Thenar flap
The correct response is Option C.
The homodigital island flap raises skin and fat overlying one digital neurovascular bundle that can be advanced distally to cover a pulp defect. As long as both digital arteries are patent, the flap can be raised on either digital artery on any finger. Because the digital nerve is raised with the flap, the overlying skin retains its sensibility (figures 2b and 2c).
The first dorsal metacarpal artery flap raises skin and fat from the dorsum of the proximal phalanx of the index finger based on branches of the radial artery and superficial radial nerve. It is useful in providing sensate coverage of the thumb, but the pedicle is not long enough to allow the flap to reach the tip of a finger.
The thenar flap and cross-finger flap raise skin from the thenar eminence and dorsal middle phalanx of a finger, respectively. Innervation is not transferred in coverage with these flaps; sensation recovery must occur with growth of the tissue surrounding the original defect. Both of these flaps require two stages, making them less appealing options.
The reverse radial forearm flap is a large, robust flap that provides excellent coverage of the hand. Its pedicle allows it to reach the tip of a finger; however, when raised in a reverse pattern with retrograde vascular flow, the flap would not bring sensation with it. In addition, the flap is too large for the defect shown in the photograph.
The apical portion at which the distal nail loses its natural adherence and transitions to the white color indicated by the arrow in diagrammatic longitudinal section of the fingertip shown is called which of the following?
A) Eponychium
B) Hyponychium
C) Lunula
D) Perionychium
E) Sterile matrix
The correct response is Option B.
The hyponychium is the junction of the nail bed (sterile matrix) and fingertip skin beneath the distal free margin of the nail. It consists of a keratinous plug and contains large numbers of polymorphonuclear leukocytes and lymphocytes. It is the first barrier of defense, preventing microorganisms from invading the subungual region.
The perionychium extends along the lateral borders of the nail. The eponychium is the distal part of the nail fold where it attaches to the surface of the nail.
The lunula is the white arc just distal to the eponychium and marks the distal end of the germinal matrix of the nail bed. It is caused by nail cell nuclei in the germinal matrix as they stream distally and upwards, creating a difference in light reflection between this area and the more distal pink sterile matrix. The nail overlying the sterile matrix, on the other hand, is pink since the nuclei within the nail cells have disintegrated. The nail beyond the point of the lunula is thus clear and the blood vessels of the nail bed show through, giving that part of the nail a pink color.
A 42-year-old man comes to the emergency department after sustaining an injury to the right hand when he caught his thumb in a table saw. Physical examination and x-ray studies show a 1.5-cm defect of the distal and volar aspect of the thumb with exposed bone. Which of the following flap and blood supply classifications is most appropriate for coverage of this defect?
A)
B)
C)
D)
E)
F)
The correct response is Option C.
The most appropriate coverage option for this 1.5-cm defect of the thumb is a Moberg flap. The Moberg flap has an axial pattern blood supply. It is indicated for defects as great as 1.5 cm on the volar surface of the thumb. It provides sensate soft-tissue coverage of thumb tip wounds.
The VY advancement flap will not cover defects as large as 1.5 cm; and the cross-finger flap, although it will cover defects as large as 1.5 cm, is inferior to the Moberg flap for defects of this type. It also does not carry innervated tissue, making the Moberg flap the most appropriate flap option for this defect.
A 70-year-old woman presents with injury to the left hand sustained while cleaning a jammed lawnmower. The tendons have been avulsed from the forearm. A photograph is shown. While waiting for transport to surgery, the patient reports worsening forearm pain in the ipsilateral extremity. X-ray studies show no fracture of the forearm. In addition to operative intervention for the hand site, which of the following is the most appropriate next step in management?
A) CT scan with contrast
B) Forearm muscle fascia release
C) Perform an axillary nerve block
D) Ulnar nerve neurolysis
E) Upper extremity angiography
The correct response is Option B.
This patient has sustained a severe avulsion-type mechanism of amputation and has developed subsequent acute compartment syndrome of the forearm secondary to avulsion of multiple flexors at their musculotendinous junctions at the forearm. This led to intracompartmental hematoma within the forearm flexors and subsequent edema, leading to increased intracompartmental pressure. When the intracompartmental pressures become significantly increased, the perfusion gradient is decreased, with subsequent capillary collapse and ischemia. This is a surgical emergency in addition to the amputated hand warranting myofascial release of the forearm compartments. If left untreated, not only will the patient’s pain be uncontrolled, but her overall morbidity will be worsened.
In the setting of compartment syndrome, additional radiologic tests are not warranted, and while a nerve block could control the pain, it does not address the underlying cause of the patient’s symptoms. Angiography is not appropriate to evaluate or treat compartment syndrome. Ulnar nerve release will not treat the compartment syndrome.
A 42-year-old man comes to the emergency department 45 minutes after he sustained an amputation injury to the long finger of the right hand (shown) when the hand was crushed in a truck tailgate as it was being closed. Physical examination shows exposed bone. No fractures are noted on radiographs of the hand. The most appropriate management of this patient’s injury is reconstruction using which of the following techniques?
(A) Atasoy-Kleinert flap
(B) Cross-finger flap
(C) Moberg flap
(D) Split-thickness skin grafting
(E) Thenar flap
The correct response is Option A.
Goals in management of fingertip amputations include wound closure, maximizing sensory return, maintaining joint function, obtaining satisfactory cosmesis, and preservation of length, especially in the thumb. Split-thickness grafting would not be appropriate to cover with exposed bone. The cross-finger flap is a pedicled, heterodigital flap that brings in durable cover from the dorsal middle phalanx skin from an adjacent finger. The donor site requires a split-thickness skin graft for coverage. The thenar flap is a regional pedicled flap based on the soft tissue of the thenar eminence. Both the cross-finger flap and the thenar flap reconstructions have the disadvantages of requiring a second stage for division and inset as well as problems with joint stiffness secondary to immobilization while awaiting vascular ingrowth from the recipient bed. The Atasoy-Kleinert flap is a homodigital V-Y advancement flap of the volar pulp tissue useful in transverse or oblique fingertip injuries with greater soft tissue on the volar aspect. The Atasoy-Kleinert flap is the best choice because it is a one-stage repair that allows primary closure of its donor site. The Moberg flap is a volar advancement flap used in thumb tip amputation coverage.
A 27-year-old man who is right-hand–dominant and works as a manual laborer comes to the emergency department for evaluation 6 hours after inadvertently incurring a high-pressure latex paint injection to the volar aspect of his left index finger. Which of the following is the most appropriate management?
A) Admission to the hospital and intravenous administration of antibiotics
B) Operative exploration
C) Radial gutter splint with follow-up in 3 days
D) Topical application of acetone
E) Warm compresses, elevation, and observation
The correct response is Option B.
Emergent incision and drainage is mandatory for high-pressure paint gun injuries. Although clinically these may appear benign and/or superficial, there is often significant underlying injury. Even small amounts of material can lead to compartment syndrome, poor perfusion, and closed space infections resulting in tissue necrosis and ultimately, amputation. History is critical, but plain films may be used to confirm the diagnosis, as both latex and the less common oil-based paints are easily seen. Grease may be radiolucent or radiopaque, depending on lead content. The most commonly injected materials are paint and grease but can also include paint solvents and fuel oil.
Nearly all reported cases involved male occupational injuries and injury to the non-dominant second or third digit, as in this case. These machines can generate pressures of 2,000 to 12,000 pounds per square inch (psi), which far exceeds the 100 psi needed to break the skin. These extreme pressures can propel injected material through the skin and subcutaneous tissues down to the bone or along fascial planes, tendon sheaths, and neurovascular bundles.
The overall rate of amputation was 30% and particularly related to the location of injury and type of material injected. Optimal time for wide surgical debridement was within 6 hours of injury. Other studies have documented an amputation rate of approximately 40% when surgery is performed within 6 hours, and an amputation rate of 57% when surgery is delayed beyond 6 hours. The amputation risk is as high as 87% without treatment or if treatment is further delayed.
None of the other interventions listed are appropriate for this type of emergent injury.
Which of the following is the arterial supply of the flap for digital tip reconstruction shown?
A) Distally based from the contralateral digital artery
B) Dorsal perforating vessels
C) Perineural perforating vessels
D) Proximally based from the ipsilateral digital artery
The correct response is Option A.
A reverse homodigital island flap is shown. It is a distally based flap that is useful in the repair of fingertip injuries. Arterial inflow is based upon the contralateral digital artery in the crossing ladder vessels of the palmar digital arch that lie just dorsal to the volar plate at each joint. The flap requires sacrifice of the ipsilateral digital artery and care must be taken to preserve the digital nerve during elevation of the skin paddle. Typically, the donor site is grafted.
A 34-year-old man who works as a pipe fitter sustains amputation of the radial three digits of the nondominant left hand. Replantation of the thumb and long finger is performed. Three weeks later, the replanted thumb becomes necrotic. Photographs are shown. Which of the following methods of reconstruction is most likely to provide the best functional outcome?
A ) Amputation and web space deepening
B ) Debridement and coverage with a radial forearm flap
C ) Distraction lengthening of the remaining thumb
D ) Pollicization of the long finger
E ) Toe-to-thumb transfer (Please note that this pictorial appears in color in the online examination)
The correct response is Option E.
Toe-to-thumb transfer has become the standard of care for thumb reconstruction when the level of loss occurs at or around the metacarpophalangeal (MCP) joint. The functional outcomes from the transfer are excellent and the donor defect, while not completely free from morbidity, is acceptable. Wound and nerve complications, such as neuroma, can be successfully managed through traditional techniques.
Revision amputation of the thumb in the patient described would be at or proximal to the MCP joint level. Even with web space deepening, there would be insufficient length of the thumb against which the other fingers could oppose.
Distraction lengthening requires a higher-quality skin envelope than exists in the patient described to tolerate the increased space that would be occupied by the thumb metacarpal. In addition, the only remaining mobile joint in this patient would be the carpometacarpal (CMC) joint. Also, the distal end of a thumb created by this technique would have poor sensation and poor durability.
Debridement and coverage with a radial forearm flap would provide high-quality tissue that could even be made sensate with coaptation of the medial and lateral antebrachial cutaneous nerves to the digital nerve stumps. However, there would still be inadequate length of the thumb with this method.
Pollicization, while less commonly used in adult than in pediatric reconstruction, can still be useful when the level of amputation occurs at the CMC joint, or when the patient cannot tolerate or will not accept microsurgical transfer of a toe. Pollicization generally moves the index finger to the thumb position; pollicizing the long finger is technically very difficult to do because of the vascular pedicle. Given that the index finger is already lost in this patient, sacrifice of the long finger would leave only two mobile fingers on this hand.
Photographs of the patient several months after great toe-to-thumb transfer are shown. Although the great toe is slightly larger than a normal thumb, recovery of function is quite good.
A 57-year-old man is referred to the office by his primary care physician for management of contracture of the little finger (shown) that has been present for more than five years. Flexion of the digit has been increasing during the past year. Surgical management is planned via a transverse palmar approach with longitudinal incisions based over the contracted cord and later converted to the necessary V-Y advancement Z-plasties. Which of the following is the most likely long-term outcome in this patient?
(A) Anesthesia of the digit
(B) Carpal tunnel syndrome
(C) Complex regional pain syndrome type I
(D) Cord recurrence
(E) Vascular insufficiency
The correct response is Option D.
Complications of Dupuytren disease have been reported to be 17% overall. Nerve injuries can be a devastating complication after surgery for Dupuytren disease. The digital nerves are displaced medially by the spiral cord, making them more prone to injury. Fortunately, nerve transection is relatively rare, reported in only 1.5% of patients with Dupuytren disease. Complex regional pain syndrome (reflex sympathetic dystrophy) may occur after Dupuytren disease, but this is an uncommon complication (approximately 4% to 8%). It can be confused with flare reaction, which can intense vasodilation; however, there is no associated pain. Infection in patients with Dupuytren disease is not significantly greater than other similar surgeries. Arterial injuries occur in less than 1% of Dupuytren cases.
Recurrence after Dupuytren is significant; a recent study placed recurrence at 18% to 24%. Other studies, with 10 €‘year follow-up, have noted that no patients were free of disease. Patients should have realistic expectations on the possible complications and recurrence risks prior to surgery.
A 25-year-old man is evaluated for thumb reconstruction after failed replantation just distal to the metacarpophalangeal (MCP) joint. The amputation was a sharp injury with no avulsion component. A photograph is shown. Which of the following is the dominant arterial pedicle for the most appropriate flap for reconstruction?
A) First dorsal metatarsal artery
B) Lateral plantar artery
C) Peroneal artery
D) Radial artery
E) Superficial circumflex iliac artery
The correct response is Option A.
The microvascular reconstruction of choice is a toe-to-thumb transfer involving the great toe. The most common arterial pedicle for this composite flap is the first dorsal metatarsal artery (~70%), a branch of the dorsalis pedis artery. The great toe can be harvested en bloc, as a trimmed flap to improve size match, or as a wrap-around soft-tissue flap for more distal or soft-tissue–only reconstructions. Less commonly, there is a dominant plantar arterial system from the plantar digital arteries via the lateral plantar artery. Communications between the dorsal and plantar systems exist between the metatarsals, and a flap with plantar-dominant inflow can be traced back to the dorsalis pedis in most cases, although the dissection is tedious. Many authors recommend vein grafting if more length is needed in a plantar-dominant flap.
This patient requires mostly restoration of length and sensibility. Reconstruction with a toe-to-thumb transfer has the advantages of transferring similar glabrous tissue with good cosmetic match. Flexion, extension, and sensation can be restored with good outcomes, according to the literature. This patient has an intact carpometacarpal joint and adequate range of motion should be maintained.
The lateral plantar artery is the arterial pedicle for the medial plantar artery fasciocutaneous flap. It does not contribute to the plantar arch. This flap is used mostly as a pedicle flap for coverage of defects on the forefoot and heel. It can be used for free tissue transfer. The deep plantar arch is an anastomotic network between the lateral plantar and dorsalis pedis arteries.
The peroneal artery is the pedicle for the free fibula osteocutaneous flap; however, this is not described for use in thumb reconstruction.
Osteoplastic reconstruction for thumb defects not involving the basilar joint have been described as both pedicle and microvascular free flaps. These involve a vascularized soft-tissue flap surrounding a nonvascularized bone graft. The radial artery is the pedicle for the radial forearm flap, which can be harvested as a soft-tissue flap around an iliac crest bone graft, or as an osteocutaneous flap. The superficial circumflex iliac artery is the pedicle for the groin flap. This is mostly described as a staged pedicled flap for osteoplastic reconstruction around an iliac crest bone graft. Both of these techniques are complicated by poor return of sensation and bone resorption. They should be used as second-line options when free toe transfer or pollicization is not available due to severity of injury or other patient-related concerns.
An otherwise healthy 50-year-old right-hand-dominant rodeo cowboy is brought to the emergency department immediately after he sustained a roping injury to the nondominant thumb. On examination, the digit is completely separated from the remaining hand, and is cool and pale. The flexor pollicis longus (FPL) tendon is attached to the amputated part, which has been avulsed from its musculotendinous junction. A photograph is shown. Which of the following is the most appropriate operative management?
A) Completion amputation and wound closure
B) Immediate toe-to-thumb transfer
C) Nonvascularized bone grafting and a reverse radial forearm flap
D) Tendon repair into the FPL muscle belly
E) Replantation with vein grafting
The correct response is Option E.
The most appropriate option for this patient is to perform a replantation with the use of vein grafts to the snuffbox for arterial inflow. Roping injuries are a combination of both an amputation as well as an avulsion, resulting in a significant zone of injury to all structures, but especially to the vessels, which sometimes have up to 4 cm of involvement with bruising of the intima and adventitia and separation of the media from the vessel walls. This zone of injury can result in anastomotic failure and digital demise if not recognized both by the mechanism of injury as well as careful examination of the structures under the operating microscope during attempted repair. Primary anastomosis in these particular injuries is most often not possible; therefore, the use of vein grafts after resection of the involved segment is an optimal strategy. The use of an end-to-side anastomosis into the radial artery at the snuffbox has been described with good success, and would be the preferred choice in this situation.
A completion amputation of the thumb at this level (just distal to the metacarpophalangeal joint) would sacrifice needed thumb length and compromise ultimate function. As the thumb is reported to be responsible for up to 40% of hand function, this would represent a significant impact to the patient.
It is difficult to repair the FPL tendon once avulsed from the musculotendinous junction, and many authors advocate for FPL resection rather than attempted repair. As the carpometacarpal joint of the thumb is intact, it will afford good range of motion of the thumb in all directions, even if the thumb serves merely as a “post” without ability to flex at the interphalangeal joint.
Nonvascularized iliac crest bone grafting with a reverse radial forearm coverage is a surgical option but would not be the primary option in this acute amputation with an intact amputated part eligible for replantation, nor would it be preferred over staged toe-to-thumb transfer for better restoration of function and appearance.
A toe-to-thumb transfer would be a good option in this patient if the thumb could not be replanted due to extensive distal injury, distal contamination, or loss of the digit during injury. In this particular case, none of those criteria are met.
A 57-year-old man has a flexion contracture involving the ring and small fingers of the left hand. A photograph is shown on page 178. During partial fasciectomy in this patient, the neurovascular bundle to these fingers is at risk for injury. Each of the following structures is a normal component of the fascia surrounding the neurovascular bundle EXCEPT
(A) Cleland’s ligament
(B) Grayson’s ligament
(C) lateral digital sheet
(D) pretendinous band
(E) retrovascular band
The correct response is Option D.
Fascial structures that encase the neurovascular bundles include Cleland’s and Grayson’s ligaments, the lateral digital sheet, and the retrovascular band. Cleland’s ligament is a thick fascial structure that lies deep to the neurovascular bundle; it arises from the side of the phalanges and courses obliquely toward the skin. Grayson’s ligament is thinner and more sheet-like than Cleland’s ligament, and is positioned superficial to the neurovascular bundle; it arises from the tendon sheath and extends to the skin. The lateral digital sheet is comprised of superficial fascia on either side of the phalanges. It receives fibers from the natatory ligament and the spiral band, and is found lateral to the neurovascular bundle. The retrovascular band is a longitudinal structure situated dorsomedial to the neurovascular bundle.
The pretendinous cord is a pathologic component of Dupuytren disease. It is an extension of the pretendinous band in the midline of the phalanges. The pretendinous band is not a component of the fascia surrounding the neurovascular bundles.
A 71-year-old woman with a long history of scleroderma has had a painful ulceration on the tip of the index finger for approximately the past year. Treatment regimens of calcium channel blockers, repeated stellate ganglion blocks, hyperbaric oxygen therapy, and wound care have been unsuccessful in resolving the lesion. Physical examination shows an area of ulceration on the index finger penetrating into the proximal interphalangeal joint (shown above). Arteriography with runoff shows digital small vessel disease. Which of the following interventions is the most appropriate management of this patient’s lesion?
(A) Conservative amputation
(B) Digital arterial bypass
(C) Distally based digital island flap
(D) Full-thickness skin grafting
(E) Ray amputation
The correct response is Option A.
In patients with established connective tissue disease and small vessel disease of the hand, the most appropriate management of painful ulcerations of the fingertip is conservative amputation. The degree of dermal bleeding at the site of amputation can be used to assess the likelihood of healing. Digital sympathectomy is also a possible management of this lesion.
Digital arterial bypass is unlikely to succeed in patients with small vessel occlusive disease.
Skin flaps should be loosely approximated without tension. Distally based digital flaps are highly unlikely to succeed in patients with small vessel disease. Full-thickness skin grafting is unlikely to succeed in this patient because the wound extends into the joint, the finger is ischemic, and the wound bed is unlikely to provide adequate vascularity for the skin graft.
Larger surgical procedures, such as ray amputation, are not indicated as a first choice in this patient, because of the increased incidence of complications and wound-related problems.
A 14-year-old boy is brought to the emergency department 30 minutes after he sustained traumatic amputation of the index, long, and ring fingers of the dominant right hand (shown) when his hand was caught in an elevator door. Which of the following is the most appropriate method of replantation?
(A) Digit by digit; index finger, long finger, ring finger
(B) Digit by digit; long finger, ring finger, index finger
(C) Digit by digit; ring finger, long finger, index finger
(D) Part by part; bone, flexor tendons, extensor tendons, nerves, arteries, veins
(E) Part by part; flexor tendons, extensor tendons, bone, arteries, veins, nerves
The correct response is Option D.
The most appropriate method of replantation in this case is part by part; bone, flexor tendons, extensor tendons, nerves, arteries, veins. This patient has acute amputations and has presented promptly to the emergency department. In addition, all amputated parts have been approximately equally well preserved. In this scenario, the longer ischemia times tolerated by digital amputations allow for increased operative efficiencies by group repair of similar parts.
Because all three digits have been equally preserved, replantation should proceed by group repair of similar parts. Therefore, the digit-by-digit options are incorrect. If the digits were in different states of preservation, with one or more digits being more mutilated than the others, then replantation would proceed digit by digit. In that scenario, the digit in the best condition would be replanted first and might be orthotopically replanted based on the clinical circumstance. In this particular instance, if the index digit were the only well preserved digit, then consideration would be given to replanting that digit in the ring position because ulnar-sided hand function is more important than index function radially.
Skeletal stability must always be restored before any soft-tissue repairs. This is usually performed with crossed K-wires. Therefore, replantation part by part &Mac255; flexor tendons, extensor tendons, bone, arteries, veins, nerves is incorrect. The exact sequence of part-by-part repair thereafter is somewhat controversial; however, the heavier structures (flexor and extensor tendons) should be repaired first, followed by microsurgery. Arterial repair usually precedes venous repair, because the venous efflux assists with identification of the most desirable veins for anastomosis or grafting. The timing of the repairs often depends on tourniquet time but may be done either before the arterial repairs or after the venous repairs.
A 36-year-old man comes for evaluation because he is dissatisfied with the appearance of his nail (shown) after burning his hand. After removal of the nail, it is clear that more than one third of the nail bed is involved. Which of the following procedures is most likely to improve the appearance of the nail?
A ) Debridement of the nail bed and full-thickness skin grafting
B ) Dermabrasion of the nail bed and placement of a silicone rubber stent
C ) Excision of the scar tissue, reconstruction with an eponychial flap, and nail bed graft from a toe
D ) Reconstruction with a cross-finger flap to the distal pad and bone graft to the distal phalanx
E ) Resection of the scar, elevation of the nail bed for advancement, and primary repair of the nail bed
The correct response is Option C.
Nail bed deformities are common after injury to the fingertip. The photograph shows that the patient has a synechia of the nail bed at the lateral aspect of the eponychial fold. In the scenario described, the problem is twofold. First, the eponychial fold is contracted and adherent to the underlying nail bed. Second, the nail bed itself is likely scarred. Therefore, dermabrasion and
stent will not affect the status of the nail bed and will not improve the deformity. Reconstruction with a cross-finger flap and bone graft is good for a hook nail deformity but is not appropriate for scarred nail bed. Excision of the scar and attempt at advancement and primary closure is likely to fail in the scenario described as it is limited to defect of 1 mm or less. Given these constraints, resection of the scar and replacement with a graft from an adjacent finger or from one of the toes along with a flap procedure on the eponychial fold is most likely to correct the deformity. Full-thickness skin grafting will not affect this patient €™s goal of improved appearance.
A 35-year-old woman presents with a fixed adduction contracture of the first web space that has not improved with splinting and hand therapy for 4 months. Medical history includes a crush injury with complex laceration to the first web and dorsal hand and index finger five months ago. A photograph is shown. Which of the following is the most appropriate plan for reconstruction of the first web space contracture in this patient?
A) First dorsal metacarpal artery flap
B) Flexor carpi ulnaris flap
C) Posterior interosseous artery flap
D) Thenar flap
E) Split-thickness skin grafting
The correct response is Option C.
Contracture of the first web space may be secondary to cutaneous scarring, skin deficiency, fibrosis of the fascia and thenar muscles, or joint contractures. Mild contractures may be isolated to the skin; however, deeper structures are most likely involved as the contracture becomes more severe. It is important to understand the mechanism of injury, length of time the contracture has been present, and any prior treatments.
Reconstruction of the first web space involves complete contracture release and resurfacing with adequate vascularized tissue. The dissection should be carried out palmarly and dorsally with release of the palmar fascia and adductor aponeurosis as needed. Intrinsic muscle and joint contractures should be addressed at this time, and a trapeziectomy may be needed to restore carpometacarpal (CMC) motion.
This patient has a severe contracture that likely involves multiple structures given her history of deep lacerations and bony injury. This requires resurfacing with thin, pliable vascularized tissue. In this setting, the posterior interosseous artery (PIA) flap is the best choice. This flap is outside the zone of injury and provides an adequate amount of vascularized tissue for resurfacing of the web space. The PIA runs between the extensor carpi ulnaris and extensor digit quinti and forms an anastomosis with the anterior interosseous artery 2cm proximal to the distal radioulnar joint.
Skin grafting alone, either split-thickness or full-thickness, should be avoided because of the inherent tendency for secondary contracture. Skin grafts may be combined with local flaps such as a 4-flap or 5-flap z-plasty in mild to moderate contractures.
Tissue flaps from the dorsum of the hand such as the first dorsal metacarpal artery fasciocutaneous flap or dorsal hand transposition flap may be good options in some patients with small- to moderate-sized skin deficits. However, this patient sustained trauma to the dorsal hand with dorsal skin lacerations. This makes a random-pattern transposition flap unreliable. The defect in question is also too large to be completely resurfaced with a first dorsal metacarpal artery (FDMA) flap. The flexor carpi ulnaris flap is useful for elbow coverage as a turn-over flap but will not reach the hand.
A 30-year-old man is scheduled to undergo transhumeral amputation after unsalvageable brachial artery occlusion. A photograph is shown. Use of targeted muscle reinnervation may allow improved functional recovery by which of the following means?
A) Better bulk and durability by preventing denervation atrophy of muscles at the amputation stump
B) Better prosthesis control by input from median and ulnar nerve signals
C) Better sensory detection in the prosthesis by positioning amputated nerve stumps closer to the skin closure
D) More precise control of an osseointegrated body-powered prosthesis
E) Preservation of greater bony length in the amputation stump
The correct response is Option B.
A body-powered prosthesis uses motion of remaining joints, such as the gleno-humeral and scapulo-thoracic joints, to control an upper extremity prosthesis.
Targeted muscle reinnervation (TMR) would not affect function of a body-powered prosthesis. TMR positions amputated nerve stumps well within the remaining muscle and far from the cutaneous closure. Current prosthetics are not yet able to detect sensation and transmit this to the patient. Having nerve stumps near the amputation closure site increases the risk for neuroma pain.
TMR has not been shown to decrease denervation atrophy of residual upper extremity muscles. TMR has gained increasing acceptance in the treatment of patients who have undergone or will undergo upper extremity amputation. Resected nerves, such as the median and ulnar nerves, can be coapted to nerve branches to remaining muscles, such as the pectoralis and deltoid. Transcutaneous EMG detectors are positioned over these reinnervation sites to detect nerve signal, which a myoelectric prosthesis can then use to better control distal joints.
TMR does not affect the amount of bony length that can be preserved in an amputation.
A 51-year-old woman is scheduled to undergo needle aponeurotomy for Dupuytren disease of the small finger. A photograph is shown. The addition of lipografting after needle aponeurotomy is most likely to decrease the rate and severity of recurrence in this patient by which of the following mechanisms?
A) Decreasing the proximity of residual cord tissue to the skin
B) Increasing the density of myofibroblast cell-to-cell contact
C) Increasing the density of the residual cord tissue
D) Inhibiting myofibroblast proliferation
E) Providing stem cells to promote collagen production
The correct response is Option D.
Fat grafting (also called lipofilling) has shown promise as a means to improve outcomes after percutaneous needle aponeurotomy for Dupuytren disease. It is believed to work by several mechanisms:
Reducing the density of cell-to-cell myofibroblast contact
Inhibiting myofibroblast proliferation via adipose-derived stem cells
Acting as an interposed tissue graft
Providing passing over the cords to replace native subdermal fat displaced by the nodules and cords
A randomized prospective trial by Kan and colleagues showed that aponeurotomy with lipofilling showed equivalent results at one year out from treatment with a much faster recovery compared with limited fasciectomy.
A 63-year-old man has the deformity of the left small finger shown in the photographs above. It has worsened over the past two years, and he has limited passive and active extension of the proximal interphalangeal (PIP) joint of the finger. The most likely cause is contracture of which of the following cords?
(A) Central and lateral
(B) Central and pretendinous
(C) Natatory and lateral
(D) Natatory and pretendinous
(E) Natatory and spiral
The correct response is Option A.
In this 63-year-old man who has limited extension of the proximal interphalangeal (PIP) joint of the left small finger that has occurred as a result of a Dupuytren contracture, the central and lateral cords are the most likely cause. Diseased cords evolve from the normal fascial bands of the hand in patients with Dupuytren disease, leading to flexion deformities of the affected joints. Fascial structures of the hand that may contribute to Dupuytren contracture include Grayson’s and Cleland’s ligaments, the lateral digital sheath, the natatory ligament, the pretendinous and spiral bands, and the superficial transverse ligament.
The central, lateral, and spiral cords cause flexion contractures of the PIP joint. The central cord arises from the pretendinous band, and the lateral cord is formed from the central digital sheath. The spiral cord is composed of the pretendinous and spiral bands, lateral digital sheath, and Grayson’s ligament. Contraction of the spiral cord results in medial and superficial displacement of the neurovascular bundle.
In addition to the contracture of the PIP joint caused by the central and lateral cords, this patient’s hand posture results from contracture of the metacarpophalangeal joint caused by the action of the pretendinous cord. The pretendinous cord does not contribute to contractures of the PIP joint.
The natatory cord is formed from the natatory ligament as it passes transversely across the palm at the level of the web spaces. It causes adduction, not flexion, contractures of the digits.
An 86-year-old farmer is brought to the emergency department because of a large dorsal wound of his nondominant left hand sustained when his hand was caught in a flail mower. After debridement is performed, examination shows normal volar structures, including nerve and tendon function, and loss of dorsal skin and tendons. Medical history includes myocardial infarction 1 month ago. An x-ray study and photograph are shown. Which of the following is the most appropriate method of reconstruction for this patient?
A) Bilaminate neodermis (Integra) and skin grafting with delayed bone grafting
B) External fixator and posterior interosseous artery flap
C) Finger fillet flaps of index and middle finger
D) Free anterior lateral thigh flap with secondary bone grafting
E) Pedicle radial forearm flap with secondary bone grafting
The correct response is Option C.
When caring for patients with mangling hand injuries, it is imperative to consider all aspects of the patient’s history and future goals. This patient would be at risk for cardiac complications if a longer procedure such as a free flap were chosen. The amount of bone loss in the index and middle metacarpals is also problematic and would most likely require multiple procedures. Just placing an external fixation and covering the wound with a local flap is also possible but will require several procedures. Bone grafting while receiving bilaminate neodermis (Integra) and skin grafts is not recommended because of the lack of subcutaneous tissue and poor blood supply. The most expeditious method of covering this patient’s wounds in one procedure is finger fillet flaps of the injured digits. Finger fillet flaps can cover a large area for reconstruction as shown.
A 27-year-old man with a cocaine addiction is brought to the emergency department one hour after sustaining amputation of the thumb of the nondominant left hand at the distal third of the proximal phalanx while using a circular saw. The amputated part was wrapped in a towel and placed on ice. Replantation is performed with an anastomosis of the ulnar digital artery to the radial artery at the anatomic snuffbox with a vein graft. Two weeks after the procedure, there is partial survival of the replanted thumb with exposure of the flexor pollicis longus. Use of which of the following flaps is most appropriate for reconstruction?
(A) First dorsal metacarpal artery
(B) Moberg
(C) Reverse posterior interosseous artery
(D) Reverse radial artery
(E) Thenar
The correct response is Option A.
A durable, sensate, well €‘vascularized reconstruction is required. The most appropriate flap for reconstruction of the defect in the scenario described is the first dorsal metacarpal artery. When paired with the first dorsal metacarpal nerve, this flap provides sensate coverage of large defects to the distal volar aspect of the thumb. Photographs are shown below.
The Moberg flap is a sensate advancement flap used to reconstruct volar thumb tip defects of up to 1 cm. This defect is too large. Use of this flap would endanger the blood flow for the replanted thumb, and it would have a high likelihood of partial flap loss.
The reverse posterior interosseous artery flap is a pedicled fasciocutaneous flap often used to reconstruct the dorsum of the hand or the first web space. A proximal extension would be required for the flap to reach the distal volar aspect of the thumb. Tip necrosis is a known complication of this nonsensate flap.
The reverse radial artery flap is often a fine choice for thumb reconstruction. In the scenario described, however, ligating the radial artery proximal to the harvested flap may compromise the vascular supply to the replanted thumb. The replanted thumb has already displayed signs of potential vascular compromise caused by the loss of the thumb tip after replantation.
The thenar flap is a random flap used to cover volar tip defects of the long and ring fingers. The defect in the patient described could not be covered with a thenar flap.
A 65-year-old man undergoes fasciectomy for Dupuytren disease affecting the left ring finger. During dissection, the ulnar digital nerve is noted to be centrally displaced on the ring finger by a Dupuytren cord. Which of the following palmar fascia structures contributes to the formation of this cord?
A) Central band
B) Cleland ligament
C) Lateral digital sheet
D) Natatory ligament
E) Septa of Legueu and Juvara
Correct answer is option C.
Except for Cleland ligament, any of the above named structures can become involved in Dupuytren contracture. Once involved in a contracture, the name of the structure is changed to include ―cord‖ (e.g., natatory ligament becomes natatory cord).
A spiral cord is formed when Dupuytren disease affects the pretendinous band, spiral band, lateral digital sheet, and Grayson ligament. The normal palmar fascia structures pass around the neurovascular bundle in a spiral fashion. As the cord forms and contracts, it eventually becomes straight. The neurovascular bundle is then displaced centrally on the digit and is distorted to spiral around the cord.
