Hand Fractures / Dislocations 01-22 Flashcards
A 25-year-old man presents to the office because of pain and swelling at the base of his dominant right thumb 3 days after a fall from his bicycle. X-ray study shows a Bennett fracture. The patient is scheduled for surgery. In addition to longitudinal traction and volarly directed pressure applied to the dorsal radial metacarpal base, which of the following best describes the appropriate reduction maneuver for this injury?
A) Abduction and pronation of the thumb
B) Abduction and supination of the thumb
C) Adduction and flexion of the thumb
D) Adduction and pronation of the thumb
E) Adduction and supination of the thumb
The correct response is Option A.
A Bennett fracture is an intra-articular fracture-dislocation of the carpometacarpal joint of the thumb that occurs following an axially loading force through a partially flexed metacarpal. A variable-sized volar ulnar fragment of the metacarpal base articular surface remains in position by attachment of the anterior oblique ligament to the trapezium. The larger fragment consisting of the remaining metacarpal base subluxates proximally, radially, and dorsally due to deforming forces from the abductor pollicis longus and the thumb extensors. Deforming forces from the adductor pollicis also cause metacarpal adduction and supination. To counteract the deforming forces of this unstable fracture-dislocation, reduction is attempted by applying axial traction to the extended thumb, palmar abduction, and pronation, while exerting pressure over the metacarpal base in preparation for insertion of Kirschner wires.
A 23-year-old man presents 1 week after an altercation, during which he sustained a spiral fracture of the metacarpal bone of the ring finger with malrotation. No reduction was performed at the time of injury. Which of the following forms of osteosynthesis is most likely to provide sufficient stability to allow early motion in this patient?
A) External fixation
B) Internal plate fixation with monocortical screws
C) Lag screw technique
D) Noncompressive intramedullary nail
E) Percutaneous Kirschner wire fixation
The correct response is Option C.
Absolute stability is achieved with constructs that heal by primary (Haversian) healing. These constructs do not allow micromotion, are low strain at the fracture site, and have high fixation stiffness. This form of bone healing occurs with absolute fracture stability, direct osteonal remodeling, and no callus formation.
Relative stability allows for indirect healing, which goes through the phases of inflammation, soft callus formation, hard callus formation, and then remodeling.
Of the choices, lag screw technique is the only one that will achieve primary healing of a fracture.
A 25-year-old man has an acute fracture of the third metacarpal on his dominant hand. An x-ray study shows a displaced oblique fracture with shortening and rotation. During open reduction, which of the following muscles is most likely attached to the fracture fragments?
A) Abductor digiti minimi
B) Extensor digiti minimi
C) Extensor indicis proprius
D) Interosseous
E) Lumbrical
The correct response is Option D.
The correct answer is the second dorsal interossei radially and third dorsal interossei ulnarly. There is little variation in atomic origins of the interosseous muscles. All interossei originate from the corresponding metacarpal shafts. The extensor indicis proprius and extensor digiti minimi muscle bellies are located in the forearm. The abductor digiti minimi muscle is attached to the 5th metacarpal.
The lumbrical originates on the flexor digitorum profundus tendon and not on the bone.
A 19-year-old college baseball player sustained an injury to his left hand when hitting the ball with a bat 6 weeks ago. The patient reports immediate pain in his palm, weakness of grip, and within hours developed tingling into his small and ring fingers, which persisted for 6 weeks despite rest. He reports continued tingling in the ulnar fingers. Standard x-ray studies of the hand show no abnormalities. A CT scan of this patient’s hand is likely to show a fracture of which carpal bone?
A) Capitate
B) Hamate
C) Lunate
D) Pisiform
E) Scaphoid
The correct response is Option B.
This college student has sustained a hook of hamate fracture that was missed on standard hand x-ray studies. Impact from the bat or from catching a pitched ball are common mechanisms of injury for a hook of hamate fracture in a baseball player. While fractures of other carpal bones may occur in baseball players, they would not produce the symptom spectrum described in the scenario.
An x-ray study from the carpal tunnel view and a CT scan will likely show the correct diagnosis. At 6 weeks, this patient is unlikely to improve with casting alone. Surgically, he may be offered open reduction and internal fixation versus resection of the bony fragment. During surgery, the flexor tendons to the small finger should be evaluated as they can sustain attritional injury next to the fracture fragment. Nerve irritation to the ulnar nerve (sensory and motor) usually resolves spontaneously after surgery, but the nerve should be examined during surgery.
A 29-year-old right-hand–dominant man presents with a right distal radius fracture after falling on his outstretched hand. He reports increasing pain and a pins-and-needles feeling in the right hand and fingers. Distal capillary refill is less than 2 seconds, and radial and ulnar arteries are readily palpable, but the patient has severe pain on passive extension of the fingers. Early compartment syndrome is suspected. Which of the following compartments is most likely to have the most increased measured pressures in this case?
A) Deep volar
B) Dorsal
C) Lateral
D) Superficial volar
The correct response is Option A.
Compartment syndrome is a devastating condition in which bleeding and/or edema within a muscle compartment surrounded and restricted by fascia can result in increased pressures leading to neurovascular compromise and muscle death. Sequelae of compartment syndrome include loss of function, Volkmann ischemic contracture, and even amputation. It typically presents with pain out of proportion to clinical examination, as well as increased pain with passive extension of the muscle bellies within the affected compartment. Signs of neurovascular compromise are often not seen until much later in the process. Compartment syndrome is most commonly associated with traumatic fractures.
Distal radius fractures are the most common cause of compartment syndrome in the forearm. The forearm musculature is contained in four separate compartments: dorsal, lateral (or mobile wad), superficial volar, and deep volar. The deep volar compartment is the most likely to develop the highest interstitial pressures early in acute compartment syndrome after traumatic distal radius fracture. This compartment houses the flexor digitorum profundus and flexor pollicis longus muscles, which are the muscles most likely to be affected with untreated compartment syndrome and responsible for distal interphalangeal flexion of the phalanges and interphalangeal flexion of the thumb, respectively.
A 32-year-old woman sustains a dorsal proximal interphalangeal (PIP) joint fracture-dislocation of the ring finger after a fall from standing. The fracture-dislocation is reduced, and the finger is splinted in the emergency department. Three days after injury, the patient presents to the office. An x-ray study demonstrates a volar lip fracture of the middle phalanx, which measures 40% of the joint. Live fluoroscopy demonstrates PIP joint congruency through an arc of motion of 20 to 100 degrees. Which of the following is the best treatment for this patient?
A) Dorsal block splint
B) Hemi-hamate resurfacing
C) Open reduction and internal fixation
D) PIP joint transarticular pinning
E) Volar static splint
The correct response is Option A.
Proximal interphalangeal (PIP) joint fracture-dislocations are generally stratified according to the percentage of middle phalanx articular surface disrupted: 30% or less, presumed stable; 30 to 50%, tenuous stability; and more than 50%, unstable. Stable fracture-dislocations (less that 30% of the middle phalanx palmar lip) are stable in full PIP joint extension. When 30 to 50% of the middle phalanx joint surface is fractured, stability is tenuous and can only be determined by clinical testing. Those fractures that require more than 30 degrees of flexion to maintain reduction are considered unstable and therefore require some form of surgical management for maintenance of reduction (dorsal block pinning, or open reduction and internal fixation).
For all fracture-dislocations, treatment methods are grouped into five broad categories: static immobilization, articular reduction, dorsal extension block splinting, open reduction and internal fixation, and volar plate arthroplasty.
Static immobilization is straightforward but generally avoided in cases of fractures involving the PIP joint, owing to the risk of overwhelming stiffness with prolonged immobilization.
Articular reduction must be serially monitored by x-ray study, and immobilization for more than 3 weeks may result in significant PIP joint stiffness.
Dorsal extension block dynamic splinting can be used for stable or tenuous fracture-dislocations. Dorsal block pinning uses the same concept as dorsal block splinting, but it requires the surgical insertion of a pin into the head of the proximal phalanx to prevent dorsal translocation of the middle phalanx with extension.
Open reduction and internal fixation can be used to fix a noncomminuted fragment that is sufficiently large enough to stabilize with small lag screws or K-wires.
Malerich and Eaton describe a procedure called volar plate advancement (advancement of the volar plate into the middle phalanx fracture defect), simultaneously restoring stability and resurfacing the damaged articular surface. Hastings and Kiefhaber describe hemi-hamate resurfacing arthroplasty (a technique used to resurface the volar lip of the middle phalanx with a hemi-hamate bone graft). Both of these resurfacing techniques (volar plate arthroplasty and hemi-hamate arthroplasty) are salvage procedures, better suited for chronic or subacute unstable fracture dislocations.
The fracture in this scenario involves 40% of the joint and is thus considered tenuous, but it achieves stable reduction at 20 degrees of flexion, allowing for treatments such as dorsal block splinting or pinning. Given a choice, nonoperative management is preferred initially, and surgical correction (dorsal block pin or open reduction and internal fixation) is reserved for those that fail nonoperative management.
A 6-year-old boy presents with a supracondylar fracture sustained during a fall on an outstretched hand. A splint with the elbow flexed less than 90 degrees is placed. The patient is screaming in pain. Examination shows the affected hand has a 3-second capillary refill. Which of the following is the most appropriate next step in management?
A) Closed reduction
B) Continued observation and application of ice packs
C) Elevation of the arm
D) Exploration of the brachial artery
E) Replacement of the current splint with an elbow extension splint
The correct response is Option A.
Supracondylar fractures are one of the most common traumatic fractures seen in children. It occurs most commonly in children 5 to 7 years of age with similar male and female incidence. The mechanism is usually from a fall onto an outstretched hand. The fracture can lead to severe forearm edema, then ischemia leading to Volkmann’s contracture.
Immobilization would be long arm casting with the elbow flexed at less than 90 degrees. Arm elevation would decrease tissue perfusion and would therefore be contraindicated. Immediate bedside closed reduction by gentle traction and elbow flexion to 20 to 40 degrees would be indicated in this case as a next step. If the closed reduction is unsuccessful or ischemia persists after reduction or recurs, urgent operative closed reduction with percutaneous pinning is required. Pins are placed to prevent recurrence. Brachial artery exploration could be required if ischemia has not resolved even after successful reduction, but not initially.
A 26-year-old man sustained a crush injury to the tip of the left middle finger with an associated fracture at the dorsal base of the distal phalanx with nail bed injury 6 months ago. No treatment was provided. Examination shows non-union of the distal phalanx. Which of the following is the most likely secondary deformity in this patient?
A) Boutonniere deformity
B) Jersey finger
C) Quadriga
D) Swan neck deformity
E) Trigger finger
The correct response is Option D.
The scenario described involves a bony mallet deformity in which a distal phalanx fracture is associated with disruption of terminal extension at the distal interphalangeal joint. If untreated, the DIP extension loss due to a non-union of a bony mallet injury may progress to a swan neck deformity through compensatory proximal phalangeal hyperextension in the setting of continued and persistent flexion at the distal interphalangeal joint (from unopposed pull of the flexor digitorum profundus tendon). A secondary swan neck deformity may occur because of dorsal subluxation of the lateral bands and attenuation of the volar plate and transverse retinacular ligament at the PIP joint level.
A jersey finger is caused by rupture of the terminal flexor digitorum profundus. A boutonniere deformity can be caused by an injury to the central slip (but not the terminal extensor tendon). Quadriga is due to loss of length of a repaired FDP tendon, causing the finger with the repaired tendon to reach terminal flexion sooner than the other fingers whose FDP tendons are of normal length. A trigger finger does not involve a fracture of the DIP joint.
A healthy 11-year-old boy is brought to the emergency department because of worsening redness and pain around the site of an injury to the middle finger of the left hand. The patient sustained the original injury 3 weeks ago while wrestling with his brother. The patient had swelling and pain of the finger, but the pain resolved quickly, so no medical care was sought. The patient’s mother reports that she noticed a small bump on the dorsum of the finger since then. However, the patient developed redness and pain 2 days ago at the same site, both of which have worsened. An image and x-ray studies are shown. Which of the following is the most likely cause of this patient’s symptoms?
A) Biting of nails
B) Exposure to Pasteurella species
C) Flexor tendon avulsion
D) Immunocompromised state
E) Trapped germinal matrix
The correct response is Option E.
This patient has a Seymour fracture—a juxta-epiphyseal open fracture—of the distal phalanx as evidenced by the eponychial disruption and fracture pattern on x-ray study. These are open fractures traditionally frequently with associated nail bed transection. Unfortunately, secondary to delay in treatment, the patient developed osteomyelitis.
These patients often present with a mallet-appearing deformity from flexion of the distal fracture segment, the nail may be disrupted (with the distal nail bed) and lay superficial to the eponychial fold, while the transected nail bed proximally (germinal matrix) becomes entrapped within the fracture, making closed reduction prone to failure. Acute treatment in the emergency department or operating room consists of nail plate removal, reduction of the trapped nail bed, irrigation and debridement of the fracture site, reduction of the fracture, nail bed repair, nail plate replacement, and immobilization. Instability or inadequate reduction warrants operative intervention and may require Kirschner wire fixation. Inadequate reduction and/or delayed treatment are critical influences of infection rates. In a study by Reyes and Ho in the Journal of Pediatric Orthopaedics, investigators reviewed acute appropriate reduction, acute partial treatment, and delayed treatment. No infections occurred in the acute appropriately managed group, whereas 15% of the patients developed infections in the partially treated group, and 45% of the delayed treatment group developed infections. Biting of nails has been associated with nontraumatic paronychial infections. There is no history of immunocompromised state, and healthy children can acquire infections with these injuries. This patient sustained the injury wrestling his brother as opposed to from an animal bite. Pasteurella is not the most frequent bacteria associated with infections in patients who have sustained Seymour fractures. Flexor tendon avulsions, also known as jersey fingers, are traditionally closed and would demonstrate lack of flexion of the distal interphalangeal joint.
A 17-year-old boy comes to the office because of ongoing pain of the right hand after he punched a wall 5 days ago. Physical examination demonstrates tenderness of the fifth carpometacarpal joint. Posteroanterior, oblique, and lateral x-ray studies taken at an urgent care facility were read as negative by the radiologist. Which of the following additional radiographic views is most likely to help confirm this patient’s diagnosis?
A) Anteroposterior with 30 degrees of pronation from full supination
B) Carpal tunnel view with wrist in full extension
C) Clenched fist lateral in neutral forearm position
D) Lateral with 15 degrees of supination from neutral forearm position
E) Posteroanterior with 45 degrees of supination from full pronation
The correct response is Option A.
Injuries to the fifth carpometacarpal joint, including subluxation, dislocation, and fracture-dislocation, are often missed with standard two-view and three-view hand images. Two views have been suggested to help detect this subtle injury:
Anteroposterior view with forearm pronated 30 degrees from full supination. This view shows more clearly the profile of the articulation between the hamate and fifth metacarpal base. (This is similar to the “reverse oblique” view, which is typically done in 45 degrees of pronation and might also be useful.)
Lateral with 30 degrees of pronation. This view is especially helpful for detecting subluxation of the metacarpal dorsally off of the hamate. In some cases, CT scan may be warranted if plain films are inconclusive.
An 11-year-old boy is brought to the office with an acute injury of the left small finger. A lateral x-ray study is shown. Which of the following is the most appropriate description of this patient’s injury?
A) Displaced Salter Harris fracture of the middle phalanx
B) Displaced Salter Harris fracture of the proximal phalanx
C) Nondisplaced Salter Harris fracture of the distal phalanx
D) Nondisplaced Salter Harris fracture of the middle phalanx
E) Nondisplaced Salter Harris fracture of the proximal phalanx
The correct response is Option A.
This is a displaced growth plate fracture of the small finger middle phalanx. There is a 90% displacement of the metaphysis relative to epiphysis. Although there is no obvious involvement of the metaphysis and, thus, the injury could be interpreted as a Salter Harris I fracture, minor concurrent involvement of some portion of the metaphysis (making it technically a Salter Harris II fracture) cannot be excluded and is quite common. The proximal and distal phalanges of the small finger are not injured.
The mnemonic “SALTER” may be used to recall Salter–Harris fracture types:
Type I: S (Slipped). The fracture occurs through the cartilage of the growth plate (physis) with an incidence of 5-7%.
Type II: A (Above). The fracture occurs above the physis, through the metaphysis. This is the most common type, occurring in 75% of patients.
Type III: L (Lower). The fracture occurs below the physis into the epiphysis. This occurs in 7-10%.
Type IV: TE (Through Everything). The fracture occurs through everything which includes the metaphysis, physis, and epiphysis. This type occurs in 10%.
Type V: R (Rammed or crushed). The growth plate (physis) has been crushed. This occurs in <1%.
A 54-year-old woman is evaluated for an injury to the proximal interphalangeal (PIP) joint of the long finger of the left hand that she sustained during a motor vehicle collision. X-ray study is shown. Which of the following methods is the most appropriate surgical management of this patient’s fracture?
A) Dynamic external fixation
B) Hemihamate arthroplasty
C) Lag screw fixation
D) PIP joint arthrodesis
E) Volar plate arthroplasty
The correct response is Option A.
This patient presents with an intra-articular, or pilon, fracture of the middle phalanx base. Typically, pilon fractures are axial load injuries to the finger resulting in impaction, comminution, central depression, and splaying of the middle phalanx fracture fragments both volarly and dorsally.
Fractures involving the proximal interphalangeal (PIP) joint are generally divided into three categories: volar rim fractures, dorsal rim fractures, and pilon fractures (volar and dorsal rim) with or without joint dislocation. Joint dislocation occurs secondary to ligamentous injury and correlates to the amount of articular surface involved in the fracture. Management of these injuries depends on the fracture type, severity, degree of articular surface involvement, extent of dislocation, and associated soft-tissue injuries. Pilon fractures due to the comminution and crush component of the middle phalanx base can be very difficult to treat. Post-traumatic osteoarthritis causing stiffness, impaired function, and pain is a known complication.
Multiple different types of dynamic external fixation devices have been described in the literature. These are mostly fabricated from K-wires with or without a rubber band traction system. The devices work by the principles of a lever and ligamentotaxis to maintain fracture reduction and joint congruency and to allow early motion for joint surface remodeling. The devices are inexpensive and relatively easy to place with experience, and can be placed using local anesthesia. Dynamic distraction external fixation has been indicated for use in pilon fractures and unstable PIP joint fracture dislocations. The constructs are usually removed 4 to 6 weeks after fracture consolidation and clinical healing is present. Most studies report 60 to 88 degrees of PIP motion with good patient satisfaction and return of function. The presence of arthritic changes on x-ray studies is common after these injuries. Pin tract infections up to 40% have been reported in retrospective studies; however, these seem to be treated with oral antibiotics alone and do not require pin removal. They do not progress to osteomyelitis.
PIP joint arthrodesis is an option for treatment in very severe pilon fractures or crush injuries with severe soft-tissue involvement; however, this sacrifices motion and should be reserved for cases where there are no other viable treatment options.
Hemi-hamate arthroplasty and volar plate arthroplasty are operations described to treat PIP joint fracture dislocations with isolated volar rim involvement. These procedures require an intact dorsal cortex of the middle phalanx base to achieve stable fixation. Both procedures are indicated for comminuted fractures involving 30 to 50% of the articular surface of the middle phalanx base.
Open reduction and internal fixation of pilon fracture with locking plates has been described, but is technically challenging and requires significant soft-tissue dissection compared with percutaneous dynamic external fixation. Lag screws are inadequate fixation in general for pilon fractures. Isolated volar rim fractures with a larger fracture fragment can be treated successfully with lag screws.
A 20-year-old rugby player is evaluated for an acute thumb injury 4 hours after falling onto his outstretched hand while being tackled. X-ray study is shown. Surgical intervention is planned. Which of the following is the most appropriate force to apply to the thumb metacarpal during reduction?
A) Abduction
B) Axial compression
C) Flexion
D) Supination
The correct response is Option A.
In a Bennett fracture, the smaller volar-ulnar fragment is retained by the anterior oblique (beak) ligament, while the abductor pollicis longus, thumb extensor tendons, and the adductor pollicis combine to distract the base of the larger shaft fragment radially, dorsally, and proximally. These distracting forces create joint incongruity, which is a relative indication for fracture reduction. These forces must be countered to reduce the fracture, thus, requiring axial distraction, pronation, and abduction of the metacarpal shaft, while simultaneously applying external pressure at the radial base of the metacarpal.
Axial compression will worsen proximal migration of the metacarpal shaft. Extension will worsen dorsal displacement, and supination will further distract the volar surfaces of the fracture fragments. Application of these forces will not promote fracture reduction.
A 30-year-old man is evaluated for a hand injury after punching a wall. X-ray study shows a fracture of the fifth metacarpal neck. Which of the following findings is most likely to require surgical intervention?
A) Angulation
B) Callus formation
C) Impaction
D) Malrotation
E) Shortening
The correct response is Option D.
Malrotation causes scissoring of the affected digit, which will adversely affect neighboring digits. This will affect activities of daily living and is an indication for operative intervention. Other indications for operative intervention include displaced intra-articular fractures, severe soft-tissue injury, unstable open fractures, segmental bone loss, and multiple fractures. Angulation is usually dorsal tip–oriented because of intrinsic and extrinsic muscle pull. A good rule of thumb is the 10, 20, 30, 40 for digits two, three, four, and five. The fourth and fifth digits have carpometacarpal joint mobility and can tolerate larger angulation. The fifth digit metacarpal may even tolerate up to 70 degrees of angulation as long as there is no extensor lag. Impaction can lead to shortening and/or angulation, which is tolerated more than rotational deformities. Similarly, shortening is well tolerated as long as there is no extensor lag. Nonoperative complications include aesthetic with loss of knuckle and possible pain in the palm from the metacarpal head. Callus formation is indicative of an old, healed fracture.
A 25-year-old man comes to the office 48 hours after “jamming” the right index finger while playing volleyball. The patient reports pain and swelling around the proximal interphalangeal (PIP) joint that prevents him from flexing the digit. Examination does not show malrotation or angulation of the fingertip, but range of motion is limited at the PIP joint because of pain. X-ray studies are shown. Which of the following is the most appropriate next step in management?
A) Arthrodesis of the PIP joint
B) Dorsal block splinting
C) Dynamic traction reduction
D) Hemi-hamate arthroplasty
E) Splint immobilization for 4 weeks
The correct response is Option C.
Dislocations of the proximal interphalangeal joint may be treated with splinting, typically dorsal block splinting, and early motion. In the setting of a volar dislocation, where injury to the central slip is suspected, splinting for 3 to 6 weeks in extension may be necessary. Splinting alone is inadequate treatment for fracture dislocations where the middle phalanx remains subluxed dorsally compared with the proximal phalanx condyles. This particular injury requires reduction prior to splinting or other methods of maintaining the joint congruity. Fracture/dislocations of the proximal interphalangeal joint that can be reduced and maintained with joint flexion can be successfully treated with either dorsal block splinting or percutaneous pinning as a dorsal block. Injury patterns amenable to this treatment typically involve <40% of the volar articular surface. The lateral radiograph demonstrates a comminuted fracture of 50 to 60% of the volar articular surface of the middle phalanx with the presence of a centrally depressed fragment; which is too large for a hemihamate graft. The AP radiograph shows comminution extending obliquely as well as in the sagittal plane, suggesting a pilon-type injury. This pattern of injury would not be reduced adequately with dorsal blocking alone. Complex fractures/dislocations of the base of the middle phalanx prove challenging to treat. Keys to success involve reduction of the dorsally dislocated middle phalanx base, restoration of articular congruity, and provision of early motion.
One useful approach to these injuries involves application of a dynamic traction device. Commercial devices are available; however, a construct composed of pins and rubber bands, described by Suzuki, allows creation of a dynamic traction device with materials available at any hospital. Outcomes from this treatment can achieve anywhere between 70 to 90% of the motion of the uninjured joint. When unstable, simple fracture/dislocations of the proximal interphalangeal joint can be treated with open reduction and internal fixation. Multiple techniques have been employed including dorsal, palmar, and midlateral approaches. Screws, cerclage wires, and even miniplates have been used. The lateral radiograph demonstrates this with the depressed articular fragment in the volar half of the joint surface. When severe comminution destroys enough of the volar half of the middle phalanx base so as to make restoration of stability unlikely, an osteochondral graft from the dorsum of the hamate between the little and ring finger metacarpal bases can be harvested and used to replace the lost articular surface. Use of this procedure requires the presence of a dorsal articular segment with some stability, to which the graft may be affixed. The AP radiograph demonstrates fracture lines extending through the dorsoradial articular surface of the middle phalanx, making hemi-hamate grafting difficult if not impossible. Arthrodesis is reserved as a salvage repair after attempts at primary repair have failed.
Which of the following is most likely an open fracture?
A) Barton
B) Colles
C) Epiphyseal
D) Salter-Harris III
E) Seymour
The correct response is Option E.
The Seymour fracture in children displaces through the epiphysis with the nail matrix interposed between the fragments. It is always an open fracture.
The Salter-Harris classification is the most commonly used method to describe the five most frequent patterns of pediatric fractures involving the physis. The classification helps explain the mechanism of injury and anticipate the consequences of the fracture upon subsequent growth. A Salter-Harris III fracture is epiphyseal but is not necessarily open.
Colles and Barton fractures are seen in the distal radius.
A 28-year-old man is brought to the emergency room because of pain, swelling, and deformity of the right small finger and a laceration over the finger after being involved in a motor vehicle collision. Physical examination shows a 7-mm laceration over the fifth metacarpal shaft. X-ray studies confirm a significantly displaced transverse metacarpal shaft fracture of the right small finger. Which of the following is the most appropriate management?
A) Closed reduction of the fracture and splint immobilization followed by 7 to 10 days of outpatient oral antibiotic therapy
B) Closed reduction of the fracture followed by splint immobilization only
C) Emergent debridement in the operating room followed by external fixation of the fracture
D) Inpatient intravenous antibiotic therapy and debridement in the operating room within 48 hours
E) Irrigation of the wound in the emergency room, splint immobilization, 24 hours of oral antibiotic therapy, and elective operative fixation of the fracture
The correct response is Option E.
This patient has a displaced Grade I open fracture of the fifth metacarpal shaft. Appropriate management includes irrigation and debridement of the wound in the emergency room, splint immobilization, and a brief course of antibiotic therapy. This allows the fracture to be managed as if it were a closed injury. Transverse shaft fractures typically are unstable and require some type of elective fixation beyond splint immobilization.
Open fractures usually are classified according to the Gustilo-Anderson scale, although outcomes of upper extremity open fractures do not necessarily correlate to this system. Grade I injuries are defined as fractures with open wounds <1 cm. Grade II fractures have open wounds measuring between 1 and 10 cm. Grade IIIA fractures have wounds >10 cm with comminution but adequate soft-tissue coverage. Grade IIIB fractures have wounds >10 cm with extensive periosteal stripping that requires soft-tissue reconstruction. Grade IIIC fractures have large wounds with associated vascular injury.
In upper extremity fractures, studies have not correlated time to operative debridement or the administration of antibiotic therapy with ultimate outcomes in terms of infection, malunion, or osteomyelitis. Factors that have been shown to correlate to poor outcomes in large-scale studies have been high injury severity score, Gustilo grade III, and fractures of the tibia/fibula. Shorter duration of antibiotic administration for open fractures has not been shown to result in a higher rate of infection. The current recommendation from the American Society of Orthopedic surgeons is a 3-day regimen of antibiotics for Grade I/II injuries and 5 days for Grade III.
Grade I injuries have only a minor soft-tissue component and there is no role for emergent surgery, hospital admission, or the need for provisional external fixation.
Closed reduction and splint immobilization are not appropriate for unstable fractures as definitive management in a healthy, young patient. In addition, there is no role for prolonged courses of antibiotic therapy. The fracture can be treated with percutaneous pin fixation or plate fixation depending on the preference of the surgeon.
The metacarpophalangeal (MCP) joint of the thumb is which of the following types of joint?
A) Ball-and-socket
B) Condyloid
C) Hinge
D) Pivot
E) Saddle
The correct response is Option C.
The metacarpophalangeal (MCP) joint of the thumb and interphalangeal joints of the index through little fingers are hinged joints and allow flexion and extension only. Lateral forces can disrupt the collateral ligaments, resulting in partial or full tears.
Condyloid joints allow flexion and extension, abduction and adduction, and circumduction, and they can be seen in the MCP joints of the index through little fingers and in wrist joints. Saddle joints allow flexion and extension, abduction and adduction, and circumduction, and they can be seen in the carpometacarpal joint on the thumb. Ball-and-socket joints allow flexion and extension, abduction and adduction, and internal and external rotation, and they can be seen in the shoulder and hip joints. Pivot joints allow rotation and are seen in the atlas and axis bones.
A 24-year-old man is evaluated because of a 1-cm metacarpal defect after sustaining a gunshot wound to the hand. In addition to operative fixation of the fracture, which of the following materials placed into the defect is most likely to promote osteogenesis?
A) Calcium hydroxyapatite
B) Cancellous autograft
C) Cortical allograft
D) Demineralized bone matrix
E) Methylmethacrylate
The correct response is Option B.
The material that will most likely provide osteogenesis is cancellous autograft.
Bony defects can be constructed by a variety of methods, and there has been an increase in the number of biomaterials that can be used. Autograft bone is obtained from the same individual, while allograft bone is obtained from another human source (i.e., cadaveric or donor). Demineralized bone matrix does not contain calcium, but retains growth factors and proteins as the nonmineralized components of bone. Calcium hydroxyapatite is a bone substitute that mimics bone in mineral structure, and gradually becomes replaced with native bone. Methylmethacrylate is used in orthopedic bone cement, and is not biodegraded or replaced, but can provide rapid structural support.
Osteoconduction refers to the replacement of the graft material through a process known as creeping substitution, where native cells from the surrounding bone break down the material and replace it with new bone. This is the primary mechanism of healing of cortical bone grafts. It is also seen in biocompatible materials that are replaced with bone, such as calcium hydroxyapatite.
Osteoinduction refers to the stimulation of bone-forming cells from surrounding host tissues, resulting in activation of progenitor cells and differentiation into osteoblasts, leading to the creation of new bone. This process occurs due to growth factors that are present in the graft material, and can be seen in cancellous bone grafts, as well as demineralized bone matrix, which contains growth factors. Osteoinduction also occurs with cortical grafts, although to a lesser extent.
Osteogenesis refers to new bone formation, which is provided from surviving cells within the graft material. In order for osteogenesis to occur, viable cells must be transferred with the graft. This is seen in autograft materials, but not in allograft materials, which are processed and may be decellularized. Cells contained within autografts can survive and produce new bone. Vascularized bone transfer may give rise to more cell viability than traditional autografts, because it maintains perfusion to the grafted bone, rather than relying on nutrients from the bed.
An 11-year-old boy is brought to the emergency department after sustaining an injury to the tip of the left long finger while playing baseball. The long fingertip is held in a flexed position. The proximal nail plate is slightly visible superficial to the eponychial fold, and a small subungual hematoma is noted. An x-ray study is shown. Which of the following is the most appropriate management?
A) Closed reduction and distal interphalangeal joint extension splinting for 6 to 8 weeks
B) Closed reduction, removal of nail plate, and percutaneous pinning
C) Open reduction, repair of nail bed, and Kirschner wire fixation
D) Repair of zone I flexor tendon avulsion
E) Suture repair of lacerations and observation for 6 weeks
The correct response is Option C.
This patient has a Seymour fracture, or an open physeal/juxta-epiphyseal fracture of the distal phalanx. These injuries present as mallet-like injuries, but they are open fractures by definition. The treatment of choice is open reduction, debridement of the fracture site, repair of associated nail bed laceration, and Kirschner wire fixation of the fracture across the distal interphalangeal (DIP) joint. The injury is secondary to hyperflexion and is essentially a Salter I or Salter II fracture of the distal phalanx. The flexed posture occurs because the terminal extensor tendon inserts on the proximal dorsal epiphysis, while the flexor digitorum profundus inserts on the metaphysis of the bone distal to the fracture site. These injuries can often be mistaken for mallet injuries or DIP dislocations. Often a flap of nail bed matrix becomes interposed between the fracture fragments, preventing closed reduction. This must be repaired. It is recommended to not discard the nail plate, because it helps maintain bone reduction. Dorsal physeal widening and flexion of the distal fracture fragment is seen on lateral x-ray studies.
Observation alone for a Seymour fracture, mallet finger, or DIP dislocation is inappropriate.
Closed reduction and DIP extension splinting is generally the treatment of choice for mallet-type injuries. These can be purely soft-tissue mallet fingers or osseous mallet fractures. Initial treatment should include closed reduction by extension or hyperextension and splinting that isolates the DIP joint in extension. Generally, the splint is worn for 6 to 8 weeks continuously, and then for a period of time at night as indicated. Compliance may be an issue with the pediatric or adolescent population, and the patient should be seen regularly to assess splint fit and skin integrity.
Closed reduction and pinning may be necessary for osseous mallet fingers with associated volar subluxation of the distal phalanx. Several techniques have been described, but this is not appropriate for a Seymour fracture. The nail bed tissue must be reduced from the fracture site to achieve anatomic reduction in this case. Also, closed treatment has an unacceptable incidence of infection, residual finger deformity from incomplete reduction, and nail deformity.
A zone I flexor tendon avulsion, or jersey finger, would present with the DIP joint held in extension. This is opposite to the presentation of this patient. In that case, the patient would require open exploration and reinsertion of the profundus tendon to the distal phalanx via bone tunnels or suture anchor.
A 29-year-old man comes to the office because of pain and the inability to flex the little finger of his dominant right hand 6 weeks after injuring it during a recreational football game. He reports that he “jammed” the finger and then pulled it back into place. He did not seek medical care at the time of the injury. He is concerned about maintaining an active lifestyle and preserving the maximum range of motion. Physical examination shows the inability to flex at the proximal interphalangeal joint. Lateral x-ray study of the finger is shown. Which of the following is the most appropriate management?
A) Arthrodesis
B) Dynamic external fixation
C) Hemi-hamate arthroplasty
D) Open reduction and internal fixation
E) Silicone implant reconstruction
The correct response is Option C.
Proximal interphalangeal (PIP) joint fracture dislocations are common finger injuries that result in pain and loss of motion. Normal PIP joint range is 0 to 110 degrees.
This type of injury normally results from an axial load applied to the finger in a hyperextended position. If more than 30 to 50% of the volar base of the middle phalanx breaks off, the joint will become unstable.
If identified early, the fracture can be managed with either open reduction and internal fixation or dynamic external fixation. At 6 weeks post injury, the fracture fragments would not be mobile, making dynamic external fixation unsuccessful. In addition, it is normally not possible to mobilize the fracture fragments in a manner that they can be reduced and fixated this far out from injury.
Silicone implant arthroplasty can provide pain relief and preserve limited PIP motion in low-demand patients such as those with rheumatoid or osteoarthritis. It would not be sufficiently durable to tolerate the lifestyle of this patient and does not provide as much range of motion as a hemi-hamate graft.
Arthrodesis will provide durable stability and pain relief even in a young patient. However, it sacrifices all motion at the PIP joint. As such, it should be reserved as a salvage option if motion-preserving options fail.
Since its description by Hastings in 1999, hemi-hamate arthroplasty has become a reconstruction of choice for unstable late dorsal fracture-dislocations, particularly those involving more than 50% of the articular surface. The dorsal central portion of the hamate is harvested as an osteocartilaginous graft. Due to the thicker articular cartilage of the distal hamate compared with the base of the middle phalanx, the bone surfaces may appear uneven even though the cartilage surface (and, therefore, the joint surface) is confluent.
Volar plate arthroplasty (VPA) avoids the need for a bone graft donor site but cannot stabilize a PIP joint if more than 50% of the volar base of the middle phalanx is missing.
A 23-year-old male rugby player is evaluated because of the inability to flex the ring finger at the distal interphalangeal (DIP) joint 2 days after injuring the finger during a match. The patient reports tenderness over the pulp and distal flexion crease. A clinical photograph and x-ray studies are shown. Which of the following is the most appropriate management?
A ) Closed reduction and percutaneous pin fixation
B ) DIP arthrodesis
C ) Extension block splinting
D ) Open reduction and internal fixation
E ) Volar plate arthroplasty
The correct response is Option D.
The clinical scenario, photograph, and x-ray studies demonstrate classic symptoms of a ?jersey finger,? or avulsion of the insertion of the flexor digitorum profundus (FDP) tendon. In this instance, the rupture involves a large bone fragment to which the FDP tendon remains attached (Type III). The large size of the bone fragment lends itself to repair via open reduction and internal fixation of the fracture. Use of mini-screws or transosseous wiring will provide suitable internal fixation. Type II (retraction of the tendon to the proximal interphalangeal [PIP] joint) and Type I (retraction to the palm) injuries can be addressed through transosseous suture reattachment or suture anchor.
Inadequate closed reduction would make percutaneous pin fixation a poor choice of treatment.
Arthrodesis offers a salvage procedure for failed or unrepaired FDP avulsion injuries. In this young patient with an acute condition, arthrodesis would be too aggressive an intervention.
Extension block splinting can be useful in volar plate injuries, which are often identified by a small, palmar avulsion fragment seen on the lateral x-ray study. This fracture would not be successfully reduced by attempts at flexion or splinting.
Volar plate arthroplasty can restore a functional articular surface following intra-articular fractures of the PIP joint but are not useful in the DIP.
A 22-year-old man comes to the emergency department after falling onto his outstretched left hand. An x-ray study and a clinical photograph are shown. Attempted reduction is unsuccessful. Reduction is most likely blocked by which of the following anatomical structures?
A) Central slip
B) Dorsal capsule and collateral ligaments
C) Flexor tendons and intrinsic muscles
D) Lateral bands
E) Sagittal bands
The correct response is Option C.
Dorsal metacarpophalangeal joint (MCP) dislocations are relatively uncommon. They occur with forced hyperextension injuries. The digit involved most commonly is the index finger, followed by the little finger.
With complete dislocation, the volar plate ruptures in the membranous proximal portion and becomes interposed in the joint. If this were the only structure blocking reduction, traction on the joint would be sufficient to draw the proximal edge of the volar plate over the metacarpophalangeal head. This is not possible in an irreducible MCP dislocation because additional taut medial and lateral structures are drawn around the narrow metacarpophalangeal neck. At the index finger, the structures include the lumbrical on the radial side and the flexor tendons on the ulnar side. At the little finger, the structures are the common tendon of the abductor digiti minimi and flexor digiti minimi on the ulnar side and the lumbrical and flexor tendons on the radial side. Central slip remains dorsal at the proximal interphalangeal joint and is not associated with the metacarpophalangeal joint. The other structures at the MCP joint would not result in a noose around the metacarpal neck and block reduction.
A 30-year-old woman comes to the office because she is unable to flex the distal interphalangeal (DIP) joint of the right long finger. An x-ray study is shown. She reports that she injured the finger 2 days ago when attempting to restrain her dog. Physical examination shows no active flexion of the DIP joint; however, the DIP joint can be passively flexed from 0 to 80 degrees. During surgical exploration, the distal end of the flexor digitorum profundus tendon is most likely to be found at the level of which of the following structures?
A ) A4 pulley
B ) Camper chiasm
C ) Central slip
D ) Sagittal band
E ) Terminal tendon
The correct response is Option A.
The injury to the patient described is commonly referred to as a €œjersey finger. € Patients have the sudden failure of fingertip-level grasp, like a football player attempting to tackle an opponent by the jersey. Injury may involve a pure soft-tissue rupture of the flexor digitorum profundus (FDP) tendon, or a portion of the volar proximal aspect of the distal phalanx may be avulsed along with the tendon. Injuries are classified based on the type of fracture and how proximally the FDP tendon has retracted. In the patient described, a large fragment of the distal phalanx base remained attached to the FDP tendon. The tendon and fragment are held in this position by the A4 pulley.
Camper chiasm is where the flexor digitorum superficialis (FDS) tendon splits to pass dorsal to the FDP tendon en route to its insertion at the base of the middle phalanx. Camper chiasm does not exist distal to the proximal interphalangeal (PIP) joint. The sagittal band is a stabilizer of the extrinsic extensor tendons over the dorsum of the metacarpophalangeal (MCP) joint. It also does not contact the FDP tendon. The terminal tendon and central slip are components of the finger extensor mechanism. They do not contact the FDP tendon.
The postoperative x-ray study shown demonstrates reduction of the bone fragments to the shaft of the distal phalanx. A Bunnell suture was used to capture the tendon and the multiple bone fragments. This suture was then passed through the distal phalanx and tied dorsally over a button.
A 28-year-old man who is an amateur motorcycle stunt driver comes to the emergency department because he has progressively worsening pain and numbness in the left hand three hours after injuring the left wrist in a motorcycle misadventure. Radiographs of the wrist are shown. He has previously fractured both scaphoids in similar accidents. The scaphoid fractures are not united. An operating room is not available for at least six hours. Which of the following is the most appropriate next step in management?
(A) Closed reduction
(B) Contrast arthrogram
(C) Contrast MRI
(D) Injection of corticosteroid into the left wrist
(E) Plaster splinting
The correct response is Option A.
The patient described has a closed right dorsal perilunate, transscaphoid, transulnar styloid fracture-dislocation. In the scenario described, with no immediate operating room availability and with worsening pain and numbness, the most appropriate treatment is closed reduction followed by splinting, which can be performed in the emergency department under conscious sedation. When an operating room becomes available, the injuries to ligament and bone can be open repaired or reconstructed.
The critical element is reduction to alleviate the numbness and pain. Splinting follows successful reduction. None of the other options listed addresses correction of the dislocation. The injection of corticosteroid, arthrogram, and MRI are not required for operative management.
Postoperative radiographs are shown.
A 17-year-old boy is referred to the office by his primary care physician for consultation regarding lack of active flexion of the distal interphalangeal joint of the ring finger of the dominant right hand. Six weeks ago, he sustained an injury to the hand while practicing with his high school football team. Immediately after the injury, the team €™s trainer initiated alternating application of hot and cold packs to the hand and gave the patient a finger splint, which he wore intermittently for five weeks. Current physical examination shows a tender mass at the distal interphalangeal joint of the ring finger. A radiograph is shown. Which of the following is the most appropriate next step?
(A) Fusion of the distal interphalangeal joint
(B) Fusion of the proximal interphalangeal joint
(C) Reduction and fixation
(D) Tendon repair with single-stage tendon grafting
(E) Two-stage tendon reconstruction with implantation of a silicone rod
The correct response is Option C.
The patient described has an avulsion of the flexor digitorum profundus (FDP) tendon from the distal phalanx, otherwise known as a jersey finger. This injury most commonly involves the ring finger. Leddy has classified these injuries into three types to direct treatment. In type 1 injuries, the proximal FDP retracts to the palm. These injuries must be repaired within two weeks to avoid a tendon graft. In Type 2 injuries, the tendon retracts to the level of the proximal interphalangeal (PIP), where it is usually maintained by a distal phalanx bone fragment by the A3 pulley. Type 2 injuries can usually be repaired without the need for a graft if treated within three months. However, over time, type 2 injuries can convert to type 1 injuries with proximal migration of the tendon to the palm. In Type 3 injuries, the bone fragment prevents tendon retraction proximal to the A4 pulley. Type 3 injuries can usually be repaired without a tendon graft, at any time, even after three months. Both type 2 and 3 injuries can be confirmed by radiography, which will demonstrate the small bone piece in the finger.
Critical to the outcome of profundus avulsion injuries is early identification of the injury.
A 28-year-old professional baseball player comes to the emergency department one hour after he sustained injuries to the index finger of the dominant right hand during a game. A radiograph is shown. Which of the following is the most appropriate management?
(A) Buddy taping the index and long fingers for three weeks
(B) Closed reduction, splinting, and repeat radiography at four weeks
(C) Extension block splinting with early protected motion
(D) Open reduction with rigid screw fixation with early protected motion
(E) Skeletal dynamic traction splinting for three weeks
The correct response is Option D.
Condylar fractures of the proximal phalanx are inherently unstable. The patient described has a displaced condylar fracture. The standard of care is open reduction and internal fixation with either screws or Kirschner wire. Screw fixation allows for early active range of motion. Percutaneous pinning or fixation with cannulated screws under C €‘arm control is a reasonable approach; however, it can be more difficult to obtain reduction using these techniques.
Nondisplaced condylar fractures can be treated with splinting alone. However, displacement is likely and radiographs must be taken frequently to monitor for displacement. Similarly, closed reduction can be performed, but frequent follow-up radiographs are needed.
Buddy taping is not appropriate because the intrinsic instability of condylar fractures of the proximal phalanx is ignored. A displacement of 2 mm also requires open reduction and internal fixation.
Skeletal dynamic traction splinting is appropriate for severely comminuted proximal interphalangeal (PIP) joint fractures such as those seen with pylon-type injuries.
A 40-year old woman who is a pitcher on a softball team has had swelling and discomfort of the ring finger of the dominant right hand since she sustained an injury during a game five days ago. She is concerned because she is not able to grip a softball and has several games scheduled over the next few months. Physical examination is limited because of edema and pain. The lateral radiograph is shown. Which of the following interventions is the most appropriate initial management of this patient €™s finger?
(A) Buddy taping of the ring and long fingers
(B) Extension block splinting of the proximal interphalangeal joint
(C) Forearm-based intrinsic plus splinting
(D) Hyperextension splinting of the distal interphalangeal joint
(E) Injection of a corticosteroid into the proximal interphalangeal joint
The correct response is Option B.
The patient described has a fracture dislocation of the proximal interphalangeal (PIP) joint, which is a frequent sports injury. The most common pattern involves the volar lip of the middle phalanx. With the stability of the PIP joint disrupted, the finger subluxes or dislocates dorsally. Early identification of the injury pattern and severity is critical to successful outcome. After evaluation and radiography, the injury should be splinted in a protected position. A dorsal semiflexed splint should protect the PIP joint in a stable, reduced position. The dorsal splint, which blocks extension, protects the injured joint from further complications.
An injection of a corticosteroid will alleviate pain and swelling but is not indicated for a fracture €‘dislocation injury. Buddy taping is useful for PIP joint collateral ligament injury. Hyperextension casting of the distal interphalangeal joint is indicated for a mallet injury or terminal tendon disruption. An intrinsic plus splint is useful for many soft tissue and bony injuries. However, the injury in the patient described requires specific positioning of the PIP joint.
A 42-year-old man comes to the office for initial consultation regarding an injury to the small finger of the right hand for which he was treated at an outside hospital one week ago. No medical records or radiographs related to the injury are available. The device on the patient €™s finger (shown) was most likely placed for correction of which of the following conditions?
(A) Central slip avulsion
(B) Fracture dislocation of the proximal interphalangeal joint
(C) Fracture of the middle phalangeal shaft
(D) Laceration of the flexor tendon
(E) Mallet finger deformity
The correct response is Option B.
Operative treatment of a fracture dislocation of the proximal interphalangeal (PIP) joint is generally indicated when more than 30% to 40% of the volar articular surface is involved. With this fragment volume, the PIP joint is unstable and displaced. Treatment options include open reduction and internal fixation, extension block pinning, or use of a dynamic traction device. Several manufactured devices are on the market; however, the simple device pictured has been shown to be very effective and can be made using easily available Kirschner wires. The technique relies on the fact that distraction of the finger will reliably reduce the fracture and restore the joint anatomy. It also allows the patient to move the joint during fracture healing, decreasing the incidence of PIP stiffness.
A simple central slip avulsion can be treated with extension splinting. The device shown would not stabilize a fracture of the phalangeal shaft. An unstable shaft fracture could be managed by pinning or plate fixation. Repair of the flexor tendon would not be helped by a dynamic intradigital traction device. A mallet injury would be treated with hyperextension splinting.
A 58-year-old woman comes to the emergency department one hour after she sustained an injury to the left hand when she tripped and fell. Physical examination shows edema and ecchymosis of the left small finger. X-ray study of the wrist is shown. Which of the following is the most appropriate management?
(A) Dynamic traction
(B) Casting
(C) Percutaneous K-wire fixation
(D) Open reduction and internal fixation
(E) Arthrodesis
The correct response is Option A.
When intra-articular fractures of the phalanges are severely comminuted or unstable, traditional methods of operative fracture fixation or immobilization may have an unacceptably high rate of late joint stiffness. Immobilization (splints, casts, or K-wire fixation) can hinder joint mobility by promoting the formation of intra-articular adhesions and extra-articular joint capsule contractures.
The dynamic traction method, however, combines movement and traction in the treatment of intra-articular fractures. Distal traction reduces and realigns the articular fragments by forces exerted on them through ligamentous attachments (ligamentotaxis). In severely comminuted articular surface fractures, open reduction may be impossible and ligamentotaxis the only way to achieve adequate fragment reduction. Movement under continuous traction also helps prevent joint stiffness and contracture. The dynamic traction splint is usually worn for six weeks, but this can vary from four to eight weeks, depending on the severity of the fracture.
Continuous passive motion following intra-articular fractures has shown to improve articular cartilage healing and regeneration. Initiation of continuous passive motion, however, requires prior reduction and stabilization of the fracture site. Pilon fractures of the PIP joint typically involve a comminuted fracture, with problematic late stiffness if standard immobilization techniques are used.
Interphalangeal joint fusion is a salvage procedure to achieve stability and pain relief, particularly in the index and small fingers, where grip strength is of high importance.
The spiral fracture shown above was most likely caused by which of the following types of forces?
(A) Axial loading
(B) Compression
(C) Tension
(D) Three-point bending
(E) Torsion
The correct response is Option E.
Spiral fractures occur when torsional loads are applied to bones. Axial loading and compression cause oblique fractures. Both tension and three-point bending can cause transverse fractures.
A 20-year-old football player twisted the small finger of the right hand when he tackled another player during a game one hour ago. Physical examination shows dislocation of the proximal interphalangeal joint of the small finger. A photograph and radiograph of the hand are shown above. Regional block anesthesia is administered, and even with flexion of the metacarpophalangeal and proximal interphalangeal joints, closed reduction is not possible. Which of the following anatomic structures are most likely blocking reduction of the dislocated joint?
(A) Central slip and lateral band
(B) Flexor digitorum profundus tendon and Cleland’s ligament
(C) Flexor digitorum superficialis and flexor digitorum profundus tendons
(D) Lateral band and Grayson’s ligament
(E) Volar plate and Grayson’s ligament
The correct response is Option A.
This is an irreducible volar dislocation of the proximal interphalangeal (PIP) joint of the small finger. In this injury, the condyle of the proximal phalanx ruptures through the transverse retinacular ligaments, usually between the central slip and the lateral band, which then become tightened around the condyle and prevent reduction, even with appropriate joint maneuvers. The central slip and lateral band structures should be identified and carefully reduced around the condyle to allow for reduction of the joint.
Cleland’s ligaments are involved in Dupuytren’s disease but not in irreducible dislocations of the PIP joint. The flexor digitorum superficialis and flexor digitorum profundus tendons are not involved in dislocations of this type. Grayson’s ligaments are not involved in irreducible dislocations of the digits.
In this patient, a slight division of the transverse retinacular ligaments between the central slip and the lateral band is required to facilitate reduction of the joint. Occasionally, division of the lateral band is required but should not be performed as initial management. This procedure was performed with a local anesthetic. Once reduction was achieved, proper functioning of the joint was verified with the full cooperation of the patient. The PIP joint was immobilized in extension; the distal interphalangeal and metacarpohalangeal joints were not splinted.
A 17-year-old boy has tenderness over the metacarpal shafts of the ring and small finger four weeks after undergoing closed reduction of a hand injury followed by use of a hand-based splint. On physical examination, there is no rotational deformity of the involved digits. Current radiographs are shown above.
Which of the following is the most appropriate management?
(A) Repeat closed reduction followed by application of a long arm cast
(B) Closed reduction and transcutaneous fixation with Kirschner wires
(C) Closed reduction and external fixation
(D) Open reduction and lag screw fixation
(E) Open reduction and miniplate fixation
The correct response is Option E.
This 17-year-old boy has displaced, angulated transverse fractures of the metacarpal shafts of the ring and small fingers. Closed reduction of the fractures and use of a hand-based splint for four weeks has not resulted in healing. Therefore, operative treatment is the most appropriate next step. This includes exploration to debride any material surrounding the fragments and open reduction of the fractures. In addition, miniplate fixation is indicated for transverse metacarpal fractures.
Repeat closed reduction and application of a long arm cast are unlikely to result in a successful reduction or lead to fracture healing.
Closed reduction and transcutaneous fixation with Kirschner wires may have been considered at the time of injury but are not appropriate four weeks later.
Closed reduction and external fixation are indicated in patients with highly comminuted fractures with or without bone loss or fractures associated with soft-tissue loss.
Lag screw fixation is appropriate for treatment of spiral and oblique metacarpal fractures in which the length of the fracture is at least twice the diameter of the bone. This technique is advantageous because it minimizes periosteal stripping.
