Hand Flashcards
A 1-year-old boy is brought to the office by his parents for consultation of a flexion deformity of the right thumb. Physical examination shows fixed flexion of the thumb at the interphalangeal joint. No other abnormalities are noted. Which of the following is the most likely diagnosis?
A) Camptodactyly
B) Clinodactyly
C) Delta phalanx
D) Macrodactyly
E) Trigger thumb
E
After 3 years of age, surgical release is generally recommended.
Trigger digit can be confused with the diagnosis of camptodactyly, which is a congenital flexion posture most often found in the small finger. Although congenital trigger thumb is related to a nodule in the tendon, the etiology of camptodactyly is less clear, with various etiologies related to skin deficit, volar plate abnormalities, and abnormalities of the lumbrical and superficialis tendons.
Abnormally angulated digits in the radial ulnar plane is clinodactyly. Clinodactyly may be associated with a delta phalanx, which is an abnormally shaped, short tubular bone within the digit.
Macrodactyly refers to an abnormal enlargement of the digit. In true macrodactyly, all structures of the digits are enlarged.
A 13-year-old girl comes to the office for consultation regarding a volar defect of the right thumb she sustained two months ago from an electrical burn to the right arm. On physical examination, bone and tendon are exposed from the metacarpophalangeal crease to the pad. Healed burn scar wounds are noted on the dorsum of the index finger along with most of the skin below the elbow. Which of the following is the most appropriate method of reconstructing this patient’s thumb?
A) First dorsal metacarpal artery flap
B) Free innervated, first web space flap
C) Moberg flap
D) Skin graft
E) Groin flap
B.
This defect is too large for reconstruction with a Moberg flap. Typically, the Moberg flap is suitable for 1- to 1.5-cm defects. A skin graft would be inappropriate because bone is exposed along the wound. Because the index finger is burned, the first dorsal metacarpal artery flap, which would usually be the first choice for this type of defect, is not available. The groin flap would be insensate and unstable and, therefore, is a poor option for reconstruction of the thumb. In the thumb, sensory restoration is crucial for hand function; therefore, an innervated flap is preferred.
The gold standard neurosensory flap is the first web space flap. The first web space flap is harvested from the lateral aspect of the great toe and the medial aspect of the second toe. The general dimensions of the flap are 6 cm transversely and 3 cm longitudinally. This flap usually is based on the first dorsal metatarsal artery, which is a branch of the dorsalis pedis artery. It also can be based on the first plantar metatarsal artery, but the dorsal branch usually is used because of difficulty with exposure of the first plantar metatarsal artery. If more pedicle length is required, the arterial dissection can be extended to include the dorsalis pedis artery.
A 25-year-old woman comes to the office for consultation regarding an injury to the left thumb (shown). During surgical repair of this injury, which of the following is the sequence in which anatomic structures will be encountered?
A) Abductor pollicis, flexor pollicis longus, volar plate
B) First dorsal interosseous, oblique pulley, volar plate
C) Junctura tendineum, extensor pollicis longus, collateral ligament
D) Sagittal bands, adductor aponeurosis, collateral ligament
E) Skin, ulnar collateral ligament, volar plate
D.
This patient has an ulnar collateral ligament injury of the thumb metacarpophalangeal (MP) joint. Although the indications for surgical repair are controversial, the pertinent anatomy is consistent. After the skin and subcutaneous tissue are divided, the sagittal bands are encountered. The sagittal bands stabilize the extensor pollicis longus over the MP joints of the thumb and travelfrom the lateral aspects of the tendon towards the flexor digital sheath. Repair of this structure is important to prevent subluxation of the tendon with thumb motion.
The adductor for aponeurosis is readily visible under the sagittal bands. This structure should also be tagged before division to facilitate accurate surgical repair. Once the adductor aponeurosis is divided, the ulnar collateral ligament is readily visible and amenable to repair.
The juncturae tendineum are extensor tendon connections on the dorsum of the hand and are not involved with the regional anatomy of the thumb. The extensor pollicis longus is usually dorsal to the area of dissection and does not require surgical manipulation.
The ulnar collateral ligament does not exist under the skin. The volar plate may be injured in a gamekeeper’s type of injury and should be assessed. A clue to a significant volar plate injury requiring repair is volar subluxation of the proximal phalanx in relation to the metacarpal.
The abductor pollicis, flexor pollicis longus, and first dorsal interosseous are out of the zone of injury and should not be surgically disturbed.
A 62-year-old man with type 2 diabetes mellitus has a nonhealing wound on the right foot six months after he sustained a degloving injury of the dorsal surface of the right foot. Radiographs obtained at the time of injury showed no abnormalities. Physical examination shows a 6 × 8-cm wound on the dorsal aspect of the foot with minimal granulation tissue, exposed tendons, and intact sensation to the sole. Which of the following is the most appropriate diagnostic study?
A) Semmes-Weinstein monofilament test
B) MRI of the foot
C) Bone scan
D) Determination of ankle-brachial index
E) Measurement of transcutaneous oxygen
E.
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.
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
D.
A 30-year-old man who works as a brick mason comes to the emergency department one hour after he sustained an injury to the right wrist when he fell backward off a 10- foot-high wall. He has severe pain in the wrist as well as numbness in the fingers and thumb. Radiographs of the wrist are shown. Which of the following is the most appropriate management?
A) Elevation of the hand and monitoring of compartment pressures with a wick catheter
B) Carpal tunnel release only
C) Carpal tunnel release and proximal row carpectomy
D) Carpal tunnel release and scapholunate arthrodesis
E) Carpal tunnel release, relocation of the lunate, and repair of the volar radiocarpal ligaments
E.
A 30-year-old man is brought to the operating room for removal of a grade 2 fibrosarcoma on the right hand. He is otherwise healthy and currently takes no medications. Physical examination shows a 4 x 5-cm lesion on the dorsal aspect of the hand. Which of the following interventions is the most appropriate preparation for dissection of the lesion?
A) Elevation of the arm for one minute and application of tourniquet pressure to 250 mmHg
B) Exsanguination with an elastic bandage and application of tourniquet pressure to 200 mmHg
C) Exsanguination with an elastic bandage and application of tourniquet pressure to 250 mmHg
D) Compression of the brachial artery, elevation of the arm for one minute, and application of tourniquet pressure to 250 mmHg
E) Compression of the radial and ulnar arteries, elevation of the arm for one minute, and application of tourniquet pressure to 250 mmHg
D.
don’t like to exsanguinate with tumor
A 24-year-old man is brought to the emergency department by ambulance because of injuries to the right leg he sustained in a motorcycle collision. Physical examination shows fracture of the tibia and fibula, thrombosis of the anterior and posterior tibial arteries, and transection of the posterior tibial and peroneal nerves just below the knee. Which of the following is the most appropriate management?
A) External fixation
B) Skeletal traction and vacuum-assisted closure of the wound
C) Revascularization and coverage with a gastrocnemius flap
D) Revascularization and coverage with a latissimus dorsi flap
E) Below-the-knee amputation
E.
A 52-year-old man who works as a watchmaker comes to the emergency department 30 minutes after he sustained avulsion of the volar skin of the dominant right thumb and index finger while using a bandsaw. Physical examination shows 2 × 2-cm wounds involving the distal phalanx of each affected digit. There is no exposed tendon or bone, and no involvement of the joints is noted. The patient requests a treatment option that will retain the most sensation. Which of the following is the most appropriate management of this patient’s wounds?
A) Radial forearm flap
B) Coverage with cross-finger flaps
C) Coverage with a thenar flap for the index finger and a cross-finger flap for the thumb
D) Split-thickness skin grafting
E) Full-thickness skin grafting
E.
Because of his occupation, this patient requires the best sensation and the most rapid treatment possible. Local flaps such as cross-finger and thenar flaps are good options but require at least two operations (inset then division) and can result in stiffness. Local flaps also have lesser return of sensibility than the other techniques listed.
Return of tactile sensibility is excellent after treatment with application of dressings. However, dressing changes for wounds that measure a total of 2 cm2 require a lengthy recovery time. This patient would undergo two to three months of dressing changes.
Skin grafting would be the next available option with acceptable sensory return. It is an operation that can be performed during local anesthesia, requires only one operation, and would allow for early motion. Interestingly, classic studies have shown that full-thickness skin grafts recover sensation better than split-thickness skin grafts.
A radial forearm flap will be excessively bulky and is not warranted. This procedure will result in inadequate sensory recovery.
A 65-year-old woman comes to the office because she has had recurrent swelling of the right wrist over the past six months. She has also had some associated numbness of the index and long fingers of the right hand. Physical examination shows swelling of the palmar aspect of the wrist. Radiographs of the hand and wrist show no abnormalities. During surgical exploration, rice bodies are identified within the carpal canal as well as granuloma formation around the flexor tendons. Which of the following is the most appropriate next step?
A) Acid-fast cultures of the tenosynovium
B) CT scan of the abdomen
C) Initiation of a course of allopurinol
D) Potassium hydroxide preparation of tenosynovium
E) Sampling of tenosynovium for amyloid
A.
Tuberculous tenosynovitis is the most frequent tuberculous infection in the hand. It may clinically simulate rheumatoid tenosynovitis. The most common pathogen is Mycobacterium marinum. Radiographs often show no abnormalities and pathology alone will often show only nonspecific tenosynovitis, but granulomas may be present. Cultures must be requested at 30 degrees Celsius to identify M. marinum.
There are several diagnostic clues for tuberculous tenosynovitis, such as proliferative synovitis occurring in the absence of a known rheumatoid or collagen vascular disease as well as the presence of rice bodies during surgical exploration. Rice bodies are infected villous bodies on the synovial surface that break off and become trapped within the inflammatory mass.
CT scan of the abdomen is sometimes recommended for women with palmar fibromatosis and arthritis because this condition may be associated with ovarian cancer. Amyloidosis can cause tenosynovitis and carpal tunnel syndrome but does not commonly produce rice bodies. Allopurinol is a treatment for gout, and potassium hydroxide stains are used to identify fungus.
A 13-year-old girl with cerebral palsy is brought to the office by her parents because she has had inability to voluntarily extend the dominant right wrist as well as weak grasp of the right hand since birth. On physical examination, when the fingers are held straight, the wrist can be brought to neutral. During grasp, there is ulnar deviation of the hand, and during extension of the fingers, there is radial deviation of the hand. Active extension of the fingers is intact, but active extension of the wrist is diminished. Dynamic electromyography confirms that function of the flexor carpi ulnaris (FCU) and flexor carpi radialis (FCR) tendons is intact. Which of the following is the most appropriate intervention for improvement in function of the hand?
A) Fusion of the wrist
B) Proximal row carpectomy
C) Transfer of the superficialis tendon to the profundus tendon
D) Transfer of the FCR tendon to the extensor carpi radialis brevis tendon
E) Transfer of the FCU tendon to the extensor carpi radialis brevis tendon
e.
During grasp, this patient’s hand deviates to the ulnar aspect, suggesting a functioning flexor carpi ulnaris (FCU) tendon. Therefore, this tendon may be transferred to augment wrist extension. Muscles that fire during grasp work well when transferred for wrist extension, whereas muscles that act while the patient attempts to release objects work better for finger extension. Because this patient’s wrist tends to deviate radially with finger release, the flexor carpi radialis (FCR) would be better transferred as a finger extensor. It is important to ensure that the FCR is working, if the FCU is going to be transferred.
Evaluation of the fingers and wrist is important before any tendon transfer. If the proximal interphalangeal and distal interphalangeal joints are passively extendable with wrist extension, then the digital flexors are relatively loose and do not require release before transfer. If the finger flexors were very tight, a transfer of the superficialis to the profundus tendon may be required to improve finger function. In cases of severe wrist contracture, a proximal row carpectomy may be necessary to allow extension of the wrist to neutral before tendon transfer
