What test does a therapist perform to confirm instability in the distal radioulnar joint?

The Piano Keys Test is specifically designed to assess instability in the distal radioulnar joint (DRUJ). During this test, the therapist applies pressure to the ulnar head while the patient's forearm is in a neutral position. If there is a displacement or excessive movement of the ulnar head, it suggests instability of the DRUJ. The name "Piano Keys" comes from the observation that the ulnar head can exhibit a "piano key" like motion similar to a key being depressed and released.

This test is crucial in cases where the integrity of the distal radioulnar joint needs to be evaluated, especially in patients who have experienced trauma or have conditions affecting wrist and forearm stability. Other tests mentioned, while useful in different contexts, focus on other structures or types of instability. For instance, the Ulnar Collateral Test targets the ulnar collateral ligament of the elbow, the Wrist Impingement Test assesses conditions related to impingement of wrist structures, and the Radioulnar Stabilization Test primarily focuses on stabilizing the joint rather than assessing for instability. Thus, the Piano Keys Test stands out as the most relevant test for confirming instability specifically within the distal radioulnar joint.