Which sign is used to assess scapholunate instability and may be positive in wrist injuries?

Which sign is used to assess scapholunate instability and may be positive in wrist injuries?

• A. Watson test
• B. Phalen's test
• C. Tinel sign
• D. Finkelstein test

Answer: (A)

The key idea is detecting abnormal movement between the scaphoid and lunate caused by injury to the scapholunate ligament. When this ligament is damaged, the scaphoid can move abnormally relative to the lunate during wrist motion. The Watson test specifically provokes that abnormal movement by loading and moving the scaphoid through its range, and a positive result is a painful clunk as the scaphoid shifts and relocates in the carpal arc. That clunk or pain indicates scapholunate instability, which is a common consequence of wrist sprains or trauma. The other tests target different problems: Phalen’s test and Tinel sign relate to median nerve compression, while the Finkelstein test assesses De Quervain’s tenosynovitis.

The key idea is detecting abnormal movement between the scaphoid and lunate caused by injury to the scapholunate ligament. When this ligament is damaged, the scaphoid can move abnormally relative to the lunate during wrist motion. The Watson test specifically provokes that abnormal movement by loading and moving the scaphoid through its range, and a positive result is a painful clunk as the scaphoid shifts and relocates in the carpal arc. That clunk or pain indicates scapholunate instability, which is a common consequence of wrist sprains or trauma.

The other tests target different problems: Phalen’s test and Tinel sign relate to median nerve compression, while the Finkelstein test assesses De Quervain’s tenosynovitis.