Wrist & Hand
Instability
Evidence: uncertain
Piano Key Sign Special Test
Orthopedic Physical Examination & Clinical Assessment Guide
What is it used for?
- Diagnosing Distal Radioulnar Joint (DRUJ) Instability.
How to Perform
- Position: Hand pronated.
- Action: Examiner pushes down on the distal ulna (ulnar head) like pressing a piano key.
Interpretation of Results
- Positive Test: The ulna springs back up (ballottable) with pain or excessive movement.