7. Hand and Wrist MCQs

DISCUSSION: The tetracycline family of medications can stain teeth and bone in skeletally immature patients and as a result should be avoided in those patients. The remaining antibiotics have no known specific contraindication to use in children. REFERENCE: Trumble TE (ed): Hand Surgery Update 3: Hand, Elbow, & Shoulder. Rosemont, IL, American Society for Surgery of the Hand, 2003, pp 433-457.

DISCUSSION: The patient has a scaphoid fracture with cystic resorption of the distal aspect of the midthird of the scaphoid. This fracture is unlikely to heal without intervention. Percutaneous pinning, closed manipulation, and bone grafting will not restore alignment. Treatment requires restoration of scaphoid length, bone grafting, and internal fixation to obtain healing with normal alignment. REFERENCES: Cooney WP, Linscheid RL, Dobyns JH, Wood MB: Scaphoid nonunion: Role of anterior interpositional bone grafts. J Hand Surg Am 1988;13:635-650. Fernandez DL: A technique for anterior wedge-shaped grafts for scaphoid nonunions with carpal instability. J Hand Surg Am 1984;9:733-737. Stark HH, Rickard TA, Zemel NP, Ashworth CR: Treatment of ununited fractures of the scaphoid by illiac bone grafts and Kirschner-wire fixation. J Bone Joint Surg Am 1988;70:982-991. Feldman MD, Manske PR, Welch RL, Szerzinski JM: Evaluation of Herbert screw fixation for the treatment of displaced scaphoid nonunions. Orthopedics 1997;20:325-328.

DISCUSSION: In a recent study on restoration of motion following zone I and zone II flexor tendon repairs in children, age was found to have no effect on the results of zone II tendon repairs. Early passive motion offered no better results than immobilization for 3 weeks. Immobilization for more than 4 weeks correlated with poorer results. REFERENCE: O’Connell SJ, Moore MM, Strickland JW, Frazier GT, Dell PC: Results of zone I and zone II flexor tendon repairs in children. J Hand Surg Am 1994;19:48-52.

EXPLANATION: The patient sustained a radial shaft fracture with subsequent apex volar malunion. As a result, his distal ulna subluxates volarly with wrist supination. Radiographs of the wrist reveal minimal arthritic changes. The most appropriate treatment option is to surgically correct his radial shaft malunion, which would indirectly address his DRUJ instability. A DRUJ ligament reconstruction or triangular fibrocartilage complex repair could be used to augment DRUJ stability; however, they might be unnecessary after correction of the radial shaft malunion. A DRUJ ligament reconstruction alone would not achieve stability of the DRUJ joint and maintain full wrist pronosupination. An ulnar head implant arthroplasty would not be reliable in eliminating the instability or the pain. Similarly, a one-bone forearm procedure might improve the patient's pain and instability but at the cost of abnormal wrist and forearm mechanics and kinematics.

The radiograph shows a complete simple dislocation of the metacarpophalangeal joint. The clue to this injury is the perpendicular alignment of the proximal phalanx to the metacarpal on the lateral radiograph. This must be differentiated from the complete complex dislocation pattern that is irreducible because of the interposed volar plate. In lateral radiographs of these injuries, the long axes of the proximal phalanx and the metacarpal are parallel. Simple dislocations are amenable to closed reduction and casting. Some authors have recommended ulnar collateral ligament repair if instability is detected on examination after reduction.

The recurrent motor branch of the median nerve supplies the thenar muscles (abductor pollicis brevis, flexor pollicis brevis, and opponens pollicis) that are primarily responsible for thumb opposition. The nerve can be injured in carpal tunnel release. A branch of the nerve also supplies the first lumbrical. The adductor pollicis and the interossei are supplied by the ulnar nerve.

The radiographs are classic for a Bennett’s fracture, which involves a fracture of the palmar ulnar aspect of the proximal phalanx. This fracture fragment is still attached to the anterior oblique ligament. The deforming forces that cause subluxation of the base of the proximal phalanx include the pull of the abductor pollicis longus as well as the adductor pollicis. Adequate reduction can be achieved by closed reduction, percutaneous pin fixation, and casting. The fragment is too small for secure internal fixation.

Which of the following is the defect in pseudohypoparathyroidism (Albright Hereditary Osteodystrophy [AHO]):

Studies demonstrate that surgical treatment of distal radius fractures in elderly people does not result in improved outcomes. Although nonsurgical treatment resulted in worse radiographic findings for this patient, these findings did not translate into worse functional outcomes.

Figure 1 reveals evidence of an intra-articular distal phalanx fracture with a distal interphalangeal (DIP) joint dorsal subluxation. This injury is unstable and requires surgical management for an active individual. Volar distal phalanx fractures are often associated with flexor digitorum profundus avulsion injuries, which are addressed concomitantly. This injury was treated with ORIF of the intra-articular fracture, pinning of the DIP joint, and repair of an avulsed flexor digitorum profundus tendon with a button on the dorsal nail plate, as shown in Figure 2. Splint immobilization would not maintain a reduction of this unstable injury. The terminal tendon is not injured in this patient but is often injured in a dorsal distal phalanx fracture with a volar dislocation. Arthrodesis of the DIP is a salvage procedure and would not be considered acutely.

EXPLANATION: This patient has a physically demanding occupation. His radiographs show a long-standing nonunion with avascular necrosis and collapse of the proximal pole. This condition is referred to as a scaphoid nonunion advanced collapse wrist (SNAC). He has advanced arthritis of the capitolunate joint, but the radiolunate joint is preserved. The best option for him would be scaphoid excision with four-corner fusion. Proximal row carpectomy would be incorrect because of the advanced arthritis of the capitolunate joint. This procedure relies on normal cartilage/joint articulation of the capitate as well as of the lunate fossa of the distal radius. Proximal pole scaphoid excision alone would not address the advanced arthritis of the capitolunate joint. Scaphoid fixation with bone grafting would not address the midcarpal arthritis and advanced proximal pole collapse.

DISCUSSION: The patient has a neglected PIP joint fracture-dislocation with comminution involving more than 40% of the volar articular surface of the middle phalanx. Volar plate arthroplasty has been advocated for the treatment of acute unstable and chronic dorsal fracture-dislocations. The volar plate is incised laterally and released from the collateral ligaments. The volar fragments of the middle phalanx are removed and a trough is created for advancement of the volar plate, which is secured with sutures secured on the dorsum of the middle phalanx beneath the extensor mechanism.

The patient has a Monteggia fracture-dislocation (proximal ulnar fracture and radial head dislocation). The posterior interosseous nerve branch of the radial nerve is the most likely to be injured and could result in weakness of thumb extension and finger metacarpal extension. Considerably less likely are injuries to the more proximal radial nerve branches supplying the extensor carpi radialis longus and brevis, resulting in weak wrist extension; the ulnar nerve supplying the digital intrinsics, resulting in weak finger abduction; the anterior interosseous branch of the median nerve, resulting in weakness of the flexor pollicis longus; and the distal median nerve, resulting in weakness of thumb opposition.

DISCUSSION: The woman has early basilar thumb arthritis. An extension osteotomy will redirect the force to the dorsal, more uninvolved portion of the first carpometacarpal joint and has been reported to alleviate pain in these patients. Arthrodesis is usually reserved for young, typically male laborers. Thermal shrinkage and denervation are considered experimental at this time. Interposition arthroplasty is typically used for more advanced stages of arthritis. REFERENCES: Tomaino MM: Treatment of Eaton stage I trapeziometacarpal disease with thumb metacarpal extension osteotomy. J Hand Surg Am 2000;25:1100-1106. Pellegrini VD Jr, Parentis M, Judkins A, et al: Extension metacarpal osteotomy in the treatment of trapeziometacarpal osteoarthritis: A biomechanical study. J Hand Surg Am 1996;21:16-23. Tomaino MM, Pellegrini VD, Burton RI: Arthroplasty of the basal joint of the thumb: Long-term follow-up after ligament reconstruction with tendon interposition. J Bone Joint Surg Am 1995;77:346-355.

The patient has Kienbock’s disease (osteonecrosis of the lunate), which presents with boggy synovitis of the wrist, decreased range of motion, and often normal radiographs. The patient’s radiographs reveal small fragments from the lunate, with increased density in the lunate body.

Originally, Burkhalter and Strait recommended bony insertion into the proximal phalanx through a drill hole. This procedure does require more surgical dissection and flexes only the MCP joints; thus it cannot extend the PIP joints directly. It does improve clawing in the fingers if the PIPs can extend with preoperative MCP flexion. The ability to extend the PIP joints is evaluated preoperatively using the Bouvier test. With the wrist in neutral position, the examiner holds the MCPs flexed and looks for the ability in that position to actively extend the PIPs. If the patient is able to do so, then the test is considered positive, and this describes "simple" clawing. In such cases, procedures that flex only the MCPs are appropriate. The insertion sites for these procedures include the proximal phalanx, the first annular pulley, and the second annular pulley. If the Bouvier test is negative, then it is best to insert the tendon grafts distally into the lateral bands. This technique has a low chance of leading to hyperextension of the PIP joints, particularly when performed with a wrist extensor motor (which leaves the flexor digitorum superficialis undisturbed) and with no preoperative hyperextensibility of the PIPs.

The structure at the tip of the forceps is the radial digital nerve to the index finger. If this nerve is accidentally cut, the patient will experience numbness to the radial aspect of the index finger. Laceration of the common digital nerve to the index-long interspace or laceration to the proper ulnar digital nerve to the index finger and the proper radial digital nerve to the long digit results in numbness at the second webspace. Numbness to the ulnar aspect of the index finger occurs after an injury to the ulnar digital nerve to the index finger. Numbness in the dorsal first webspace results from an injury to the dorsal radial sensory nerve, which is not located in the palm.

DISCUSSION: The radiographs reveal a gap between the scaphoid and lunate bones, indicative of disruption of the scapholunate ligament complex. The three components of the complex are the dorsal scapholunate ligament, the volar (or palmar) scapholunate ligament, and the proximal fibrocartilaginous membrane, listed in decreasing yield strength. Disruption of the stout dorsal interosseous ligament is required for scapholunate dissociation to occur.

DISCUSSION: The patient has an evolving acute carpal tunnel syndrome. Initial management for this injury is to relieve all external pressure that may elevate the neural compression. Surgical decompression of the median nerve at the carpal tunnel is the optimal intervention. Further nonsurgical interventions (cast removal or further bivalving) are insufficient to alleviate the neural compression.

DISCUSSION: Ball and associates reported that “horseback riding was more dangerous than motorcycle riding.” In a 10-year study of major traumatic injuries, they reported that 151 (2%) of 7,941 trauma patients had major equestrian injuries (injury severity score > or = 12). Injuries included the chest (54%), head (48%), abdomen (22%), and extremities (17%). Only 9% of riders wore helmets, and 64% believed the accident was preventable. The authors noted that “helmet and vest use will be targeted in future injury prevention strategies.” In another study, Frankel and associates noted that helmet use was only documented in 34% of riders. Although orthopaedic injuries are common, knee pads, wrist guards, boots, and quick release stirrups would most likely have less impact on injury prevention.