20241107 Wrist disorders P3a Dr Ba Huang

Which of these is the most important for scapholunate joint relationship?

• A. Palmar Scapholunate ligament

• B. Dorsal scapholunate ligament

• C. Proximal scapholunate ligament

• D. Dorsal radiocarpal ligament

• E. Dorsal intercarpal ligament

A 28-year-old woman fell on her right wrist while rollerblading 6 days ago. She was seen in the emergency department at the time of injury and was told she had a sprain. Examination now reveals dorsal tenderness in the proximal wrist but no snuffbox or ulnar tenderness. Standard wrist radiographs are normal. What is the next most appropriate step in management?

• A. Arthroscopy of the wrist

• B. CT of the wrist

• C. Bilateral PA clenched fist radiograph

• D. Electromyography and nerve conduction velocity studies

• E. AP and lateral radiographs of the forearm

Answer explanation

When considering the diagnosis of scapholunate ligament injury, standard radiographic views of the hand will not always reveal widening of the scapholunate gap. Although MRI may reveal injury to the ligaments, the PA clenched fist view can be obtained in the office during the initial patient visit. Arthroscopy is not a first-line diagnostic tool.

A 40-year-old right-handed professional football player reports persistent right wrist pain after falling during a game 5 days ago. A radiograph is shown in Figure. Management should consist of

• A. Immobilization in a short arm thumb spica cast.

• B. Immobilization in a long arm thumb spica cast.

• C. Arthroscopic repair and percutaneous pinning.

• D. Open repair and percutaneous pinning.

• E. Dorsal capsulodesis.

Answer explanation

The radiograph reveals an increased distance between the scaphoid and the lunate, which is indicative of scapholunate disassociation. A ring sign is also present, which represents the distal pole of the scaphoid viewed end on in a palmarly flexed position. In the acute setting, the scapholunate can be repaired. Open repair and percutaneous pinning is the treatment of choice. Dorsal capsulodesis is performed in the chronic setting if such an injury is initially missed.

A 24-year-old event crew fell 12 feet off a ladder while preparing a set. As he tried to brace his fall, he landed directly on his extended and ulnarly deviated left hand. He was taken to the local hospital where radiographs were taken. What additional information is most necessary to obtain before next step of management?

• A. Distal vascular examination

• B. Neurological examination

• C. Wrist MRI

• D. DRUJ stability assessment

• E. Allen test

In the type of injury this patient has sustained, what is the most likely order of structural failure?

• A. Scapholunate ligament -> disruption of capitolunate articulation -> disruption of lunotriquetral articulation-> failure of dorsal radiocarpal ligament

• B. Scapholunate ligament -> disruption of lunotriquetral articulation-> disruption of capitolunate articulation-> failure of dorsal radiocarpal ligament

• C. Scapholunate ligament -> disruption of capitolunate articulation-> failure of dorsal radiocarpal ligament-> disruption of lunotriquetral articulation

• D. Failure of dorsal radiocarpal ligament-> Scapholunate ligament -> disruption of capitolunate articulation -> disruption of lunotriquetral articulation

• E. Failure of dorsal radiocarpal ligament-> Scapholunate ligament-> disruption of lunotriquetral articulation-> disruption of capitolunate articulation