Hand - Fractures - Dislocations Flashcards
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 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.
Which of the following is the most appropriate management of the fracture shown in the radiograph (not available) above?
(A) Buddy taping
(B) Extension block splinting
(C) Stack splinting
(D) Closed reduction and longitudinal pin fixation
(E) Open reduction and internal fixation
The correct response is Option D.
This patient has a type IV mallet injury in which greater than 30% of the articular surface of the distal phalanx has been avulsed. The most appropriate management of this patient’s fracture is closed reduction and longitudinal pin fixation. Because most of the collateral ligament remains attached to the avulsed fragment, the distal phalanx is subluxed on the middle phalanx. In order to correct this deformity, closed reduction and longitudinal Kirschner wire immobilization or open reduction with a pull-out wire technique should be performed. This will restore articular congruity and reduce the subluxed joint, preventing the development of osteoarthritis. Most type IV mallet injuries can be reduced with a closed technique alone; open reduction should be considered only if closed reduction cannot be achieved.
Buddy taping is more appropriate for dislocations of the metacarpophalangeal and proximal interphalangeal joints but will not immobilize the distal interphalangeal joint in extension. Extension block splinting, which again does not immobilize the distal interphalangeal joint, is a useful rehabilitation technique in patients with dorsal dislocations of the proximal interphalangeal joint.
Stack splinting is more appropriate for correction of a type I mallet injury in which the tendon is avulsed from the proximal dorsal base of the distal phalanx. The stack splint immobilizes the distal interphalangeal joint in extension, allowing healing of the avulsed tendon to the distal phalanx. Stack splinting should also be used following suture repair in a patient with a type II mallet injury, which manifests as an open laceration of the terminal extensor tendon.
A 45-year-old man who has had pain, swelling, and ecchymoses over the ulnar aspect of the thumb metacarpophalangeal joint since falling on his outstretched hand three days ago. On examination, a tender mass can be palpated.
Which of the following is the most appropriate management?
(A) Application of a thumb spica splint
(B) Application of a thumb spica cast
(C) Closed reduction
(D) Open reduction
The correct response is Option D.
Open reduction is the most appropriate management of this patient’s deformity. These findings are consistent with a classic Stener lesion, in which the ulnar collateral ligament (UCL) avulses and retracts proximally. The interposed adductor aponeurosis precludes primary healing; the UCL will not heal properly without contact at the site of avulsion. Avulsion of the UCL can occur with or without a bony fragment. A mass can be palpated. Laxity of the ulnar capsule will occur and will not improve with immobilization of the fracture, resulting in chronic pain and instability. Open reduction and internal fixation should be performed to effectively restore contact between the fracture fragments and allow the fracture to heal.
In patients who have partial tears of the UCL, operative repair is indicated if collateral ligament instability is greater than 30 degrees during stress in both full extension and semi-flexion. Conservative management is recommended instead for incomplete ligament tears not associated with instability.
Appropriate surgical repair of this injury includes debridement of the fracture fragment, division of the adductor aponeurosis, and anchoring of the residual UCL to the small area of decorticated proximal phalanx using sutures. The adductor aponeurosis is repaired after the UCL is attached. The repaired ligament can be protected with a transarticular Kirschner wire and a cast for four weeks. After the cast is removed, a thumb spica splint should be worn for four weeks.
As mentioned above, splint immobilization or closed reduction would be ineffective in restoring contact between the fracture fragments in this patient.
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 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.
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 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 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 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 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 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.
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 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 hand 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
Correct answer 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.
A 25-year-old man comes to the emergency department six hours after sustaining an acute dorsal dislocation of the proximal interphalangeal joint of the ring finger of the dominant right hand. Following reduction, the joint is stable when flexed approximately 30 degrees but is unstable in full extension. Postreduction lateral radiographs show that approximately 20% of the volar articular surface is avulsed from the base of the middle phalanx. Which of the following is the most appropriate initial management?
A) Extension-block splinting
B) Hemi-hamate arthroplasty
C) Repair of the torn collateral ligaments
D) Screw fixation of the fracture fragment
E) Volar plate arthroplasty
Correct answer is option A.
Acute dorsal dislocation of the proximal interphalangeal joint is a complex problem that requires various approaches to treatment depending on the percentage of articular surface disrupted and the presence of impaction. Generally, if only 20% of the volar articular surface is avulsed from the base of the middle phalanx, when the fracture is reduced, there is sufficient collateral ligament attached to both the volar lip fragment and the majority of the middle phalanx to bring the fragments into close apposition. Extension-block splinting can safely be performed up to a 30-degree angle block. If more flexion is required to reduce the fragments or maintain stability, then closed reduction and splinting is probably not adequate because unacceptable flexion contracture may result. In such cases, the wound may be opened and screw fixation of the fracture fragment may be indicated. In cases of comminution, impaction, or greater amounts of articular loss, a volar plate arthroplasty or hemi-hamate arthroplasty may be indicated. Other dynamic splinting methods of treating these injuries in certain cases are the Agee force-couple technique and the Schenck splint technique. In summary, the maximum percentage of middle phalanx joint avulsion that is acceptable for closed reduction is approximately 30% to 40% and no more than 30 degrees of flexion can be accepted to maintain reduction. When extension-block splinting is used, generally after approximately two weeks of splinting, the finger is gradually extended or buddy taped to an adjacent finger to start controlled extension. Prolonged flexion can result in permanent contracture.
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 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
Correct answer 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 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 20-year-old college basketball player sustains a dorsal dislocation of the metacarpophalangeal joint of the dominant index finger. Repeat attempts at closed reduction are unsuccessful. Which of the following structures are the most likely cause of the unsuccessful closed reduction?
(A) Extensor indices, lumbrical muscle, and flexor digitorum profundus
(B) Flexor digitorum profundus, volar plate, and sagittal bands
(C) Lumbrical muscle, volar plate, and flexor digitorum profundus
(D) Sagittal bands, extensor indices, and lumbrical muscle
(E) Volar plate, sagittal bands, and extensor indices
The correct response is Option C.
The lumbrical muscle, volar plate, and flexor digitorum profundus tendons are most likely interfering with reduction of the index finger dislocation. Dorsal dislocations are uncommon injuries that occur as a result of forced hyperextension. The membranous proximal portion of the volar plate ruptures and becomes interposed dorsally between the base of the proximal phalanx and the dorsal metacarpal head. Reduction can be accomplished by flexing the wrist, which loosens the flexor tendons, and then applying pressure, directed distally and volarly, to the base of the proximal phalanx. In patients with complex dislocations, open reduction is required because the volar plate lies in the joint space, blocking a successful closed reduction. With dislocations of the metacarpophalangeal joint, the flexor digitorum profundus tendon lies ulnar to the joint and the lumbrical muscle lies radial to the joint. The sagittal bands and extensor indices are dorsal structures that are not involved.
A 23-year-old man is brought to the emergency department after twisting the long finger of his dominant right hand while playing basketball. Physical examination shows dorsal instability of the proximal interphalangeal (PIP) joint. X-ray study shows a volar buttress fracture involving 40% of the articular surface of the base of the middle phalanx. X-ray joint reduction is attained by passively flexing the PIP joint to 30 degrees. Which of the following is the most appropriate management?
A) Dynamic force-coupler external fixation
B) Extension block splinting
C) Hemi-hamate reconstruction of the volar buttress
D) Open reduction and internal fixation of the fracture fragments
E) Volar plate arthroplasty
Correct answer is option B.
If the PIP fracture/dislocation can be maintained stable with 30 degrees of flexion, then this is suitable to treat by extension block splinting. This will be the case with an approximate 40% volar articular fracture of the base of the middle phalanx. There is a risk of late flexion contracture if greater than 30 degrees of flexion is required to maintain PIP joint stability. More complex injuries may be treated with force-coupler dynamic splinting or with hemi-hamate reconstruction. For a larger fracture fragment with greater instability, open reduction and internal fixation may be required. Volar plate arthroplasty may be suitable with more chronic injuries and is limited to 60% of the articular surface.
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 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
Correct answer 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 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.
A 35-year-old woman has an open fracture of the index finger metacarpal after sustaining a gunshot wound to the hand. Physical examination shows a 2.5-cm defect of the skin; radiographs show a 2-cm segmental defect of the metacarpal. The patient is to undergo single-stage reconstruction using a distally based posterior interosseous flap with vascularized bone.
Harvest of the flap with a cuff of which of the following muscles will maintain the blood supply to the bone?
(A) Extensor carpi radialis brevis
(B) Extensor carpi ulnaris
(C) Extensor digiti minimi
(D) Extensor pollicis longus
(E) Supinator
The correct response is Option D.
The vascular supply of the ulna can be maintained by harvesting the distally based posterior interosseous flap with a cuff of the extensor pollicis longus muscle. In this patient who has a 2-cm segmental defect of the metacarpal, vascularized bone from the ulna is appropriate for single-stage reconstruction. Other reconstructive options include the radius, scapula, fibula, humerus, and iliac crest. The radial forearm flap may also be harvested as an osteocutaneous flap for reconstruction of the metacarpal.
To determine the cutaneous portion of the posterior interosseous flap, a line is drawn from the lateral epicondyle of the humerus to the ulnar head with the forearm in full pronation. The cutaneous branch of the posterior interosseous nerve, which must be incorporated in the flap, lies 1 cm distal to the midpoint of this line. The posterior interosseous artery lies deep to the deep fascia, and the septum passes between the extensor carpi ulnaris and extensor digiti minimi. After the artery has been identified, the surgeon dissects distally to the supinator, taking care to identify and preserve the posterior interosseous nerve. A 5- to 7-cm segment of bone can be harvested by dissecting through of a portion of the extensor pollicis longus while leaving a cuff of muscle attached to the bone.
Although free iliac crest corticocancellous grafts can be used to reconstruct metacarpal defects, vascularized bone graft is often preferred instead if the defect is large or the soft-tissue envelope has poor quality.
The extensor carpi radialis brevis and supinator muscles do not supply perforators to the ulna.
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 22-year-old man who has consumed alcoholic beverages punches a concrete wall with both hands and sustains multiple metacarpal fractures. Which of the following will cause the most significant long-term hand impairment in this patient?
A ) Fifth metacarpal neck fracture with 40-degree angulation
B ) Fourth metacarpal neck fracture with 35-degree angulation
C ) Fourth metacarpal shaft fracture with 10-degree angulation
D ) Third metacarpal neck fracture with 25-degree angulation
E ) Third metacarpal shaft fracture with 0-degree angulation
The correct response is Option D.
Angulation is better compensated for in the ring and little fingers. The carpometacarpal (CMC) joints of these digits have 20 to 30 degrees of mobility in the sagittal plane. Angulation deformities in the little finger up to 40 to 70 degrees have been followed and found to have no functional impairment.
However, because of the lack of compensatory CMC motion in the index and long metacarpal neck fractures, there is universal agreement that residual angulation greater than 10 to 15 degrees should not be accepted.
Metacarpal shaft fractures generally require reduction for angulation greater than 30 degrees in the little finger, 20 degrees in the ring finger, and any angulation in the long and index fingers.
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 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.
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 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
Correct answer 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.
The radiograph shown above is from a 12-year-old boy who sustained a thumb fracture. According to the Salter-Harris fracture classification, which of the following is the most appropriate classification of this fracture?
A) Type I
B) Type II
C) Type III
D) Type IV
E) Type V
Findings on this child’s radiograph are consistent with a Salter-Harris type II fracture in which the fracture has proceeded through the diaphysis of the proximal phalanx of the thumb and the epiphyseal plate.
The Salter-Harris classification describes fractures involving the epiphyseal plate in children. The degree of growth disturbance correlates directly with the level of fracture classification.
In type I fractures, the epiphysis is separated from the metaphysis; the diaphysis and articular surface are unaffected.
Type II fractures involve a small fracture of the metaphysis and separation of the epiphysis from the metaphysis.
In type III fractures, the epiphysis is fractured and the articular surface is involved.
Patients with type IV fractures have involvement of the diaphysis, epiphyseal plate, and articular surface.
In type V fractures, the epiphyseal plate is compressed; the metaphysis is unaffected.
In children with Salter-Harris type I or type II fractures, appropriate management is closed reduction, followed by casting or pin fixation. Management of type III, type IV, and type V fractures is similar but should also include restoration of the articular surface.
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 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 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.
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 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 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
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 25-year-old male motorcycle enthusiast presents to the clinic four days after sustaining an injury to his left thumb during a fall while riding. He reports significant pain, swelling, and difficulty grasping objects. Physical examination reveals tenderness at the base of the thumb and limited range of motion. Radiographs confirm the fracture shown in the image. Closed reduction of the fracture followed by percutaneous pin fixation is planned. In addition to longitudinal traction on the thumb while exerting pressure over the dorsoradial aspect of the metacarpal base, which of the following is the most appropriate reduction maneuver?
(A) Palmar abduction and pronation of the thumb
(B) Palmar adduction and pronation of the thumb
(C) Palmar abduction and supination of the thumb
(D) Palmar adduction and supination of the thumb
Correct answer is option (A): Palmar abduction and pronation of thumb.
Bennett fracture is a fracture subluxation of the thumb carpometacarpal (CMC) joint. The causative mechanism is axial overload along the first metacarpal with simultaneous flexion. The palmar oblique ligament holds the palmar marginal fragment in its anatomic position. The distal part of the first metacarpal is adducted and supinated by the adductor pollicis, and the metacarpal is also displaced proximally by the abductor pollicis longus muscle.
The treatment goals are to reduce the thumb metacarpal in the CMC joint and restore the articular surface. Reduction is achieved by axial traction, pronation of the thumb, and abduction of the extended thumb while a volarly directed force is applied to the metacarpal base.
References
1. Wong VW, Higgins JP. Evidence-based medicine: management of metacarpal fractures. Plast Reconstr Surg. 2017;140(1):140e-151e. doi:10.1097/PRS.0000000000003470
2. Fricker R, Kastelec M, Nuñez Vasquez F, Axelrod TS. Metacarpal, Bennett fracture. AO Surgery Reference. https://surgeryreference.aofoundation.org/orthopedic-trauma/adult-trauma/thumb/metacarpal-bennett-fracture
3. Sasson DC, Shah ND, Yuksel SS, Kearney AM, Brandt K, Gosain AK. A fourteen-year review of practice patterns and evidence-based medicine in operative metacarpal fracture repair. Plast Reconstr Surg Glob Open. 2022;10(1).
A 7-year-old boy is brought to the emergency department one hour after sustaining a fracture of the small finger of the non-dominant left hand when he fell down a flight of stairs. A radiograph of the left hand is shown. Which of the following is the most likely diagnosis?
A) Extra octave fracture
B) Fracture-dislocation
C) Salter Harris type I fracture
D) Salter Harris type II fracture
E) Salter Harris type III fracture
Correct answer is option A.
This is an extra octave fracture that does not involve the physis. The fracture line is very close to the physis but is above it. Forty-one percent of pediatric hand fractures involve the physis. Most involve the phalanges, particularly the proximal phalanx. The reason for this high rate is that the collateral ligaments insert into the epiphysis.
All Salter-Harris-type fractures involve the physis. Traditionally, pediatric physeal fractures are described using the Salter-Harris classification system. There are five types of Salter-Harris fractures (see below). Type I fractures are transphyseal. Type II are transphyseal but exit through the metaphysis. Type III are transphyseal fractures that exit the epiphysis and the joint. Type IV fractures traverse both the epiphysis and physis, exiting through the metaphysis. Type V fractures describe crush injuries to the physis.
The joint has not been affected in the fracture described and would therefore not be considered a fracture dislocation. If it had involved the physis, this extra octave fracture would likely have been a Salter Harris Type II fracture, the most common type of fracture in this population.
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. See current radiographs shown. 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
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.
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 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 34-year-old man presents to the emergency department after a football injury. An X-ray is taken in the ED, and a failed attempt at reduction is performed. Which structure is most likely impeding the reduction of the joint?
A. Central slip
B. Collateral ligaments
C. Sagittal bands
D. Flexor digitorum superficialis
E. Volar plate
Correct answer: E. Volar plate
The phalangeal joints have numerous stabilizers to prevent dislocation during normal range of motion. When these stabilizers are disrupted, dislocations can occur. The collateral ligaments, dorsal capsule, sagittal bands, and volar plates all contribute to maintaining joint alignment.
When a dislocation occurs, these structures can be injured. In dorsal dislocations, the volar plate, which prevents hyperextension, may be injured or torn. In some cases, the volar plate can slip between the joint surfaces, preventing reduction of the joint. Additionally, in some instances, the flexor digitorum superficialis may prevent reduction.
The collateral ligaments, sagittal bands, and triangular ligaments, when injured, do not block reduction due to their location around the joint and involvement in dorsal dislocations. The central slip is located dorsally and distal to the proximal interphalangeal (PIP) joint, meaning it would not block reduction in this case. However, if the central slip is injured and not repaired, it can lead to a boutonnière-like deformity.
In lateral PIP joint dislocations, the proximal phalanx can become wedged between the lateral bands and extensor tendons. However, this mechanism is not typically seen in dorsal dislocations.
References:
1. Bamal R, Bindra R. Open reduction of neglected dislocations of the proximal interphalangeal joint.
J Hand Surg Am. 2020;45(10):991.e1-991.e7.
doi:10.1016/j.jhsa.2020.07.002
2. Saitta BH, Wolf JM. Treating proximal interphalangeal joint dislocations.
Hand Clin. 2018;34(2):139-148.
doi:10.1016/j.hcl.2017.12.004
Clinical Scenario:
A 28-year-old male presents to the emergency department after a sports-related injury to his right hand. He reports that his middle finger was forcefully hyperflexed while attempting to catch a basketball. On examination, the patient has pain and swelling over the proximal interphalangeal (PIP) joint of the middle finger, with a limited active range of motion and noticeable extensor lag. Imaging confirms a volar dislocation of the PIP joint without associated fractures.
The injury is reduced in the emergency department by applying traction to the digit and dorsally directed pressure to the volar aspect of the middle phalanx, with the wrist and metacarpophalangeal joint held in flexion. Post-reduction imaging confirms no fracture.
Question:
What is the most appropriate next step in managing this patient’s injury?:
A. Buddy tape the injured finger to the adjacent digit and encourage early motion.
B. Immobilize the PIP joint in extension with a splint for 4–6 weeks while allowing distal interphalangeal (DIP) joint mobility.
C. Apply a short arm radial gutter cast for immobilization of the wrist, hand, and injured digit.
D. Perform open reduction and internal fixation (ORIF) to stabilize the joint.
E. Apply dynamic traction to achieve joint stabilization and allow early motion.
Correct Answer: B. Immobilize the PIP joint in extension with a splint for 4–6 weeks while allowing distal interphalangeal (DIP) joint mobility.
Explanation:
The patient has suffered a central slip injury associated with a volar PIP dislocation. Extension splinting of the PIP joint for 4–6 weeks is the standard management to allow healing of the central slip. The DIP joint can remain free to maintain mobility and prevent stiffness. Other management options are inappropriate for the following reasons:
• Option A: Buddy taping is appropriate for stable dorsal dislocations but not for volar dislocations with central slip injuries.
• Option C: A short arm cast is bulky and unnecessary unless the patient is noncompliant.
• Option D: ORIF is indicated only in the presence of a fracture or when closed reduction is unsuccessful, neither of which applies here.
• Option E: Dynamic traction is reserved for pilon fractures of the PIP joint and is not indicated in isolated dislocations without fractures.
