Grind Test for Thumb Carpometacarpal (CMC) Joint Osteoarthritis

Test Procedure:
- Support the patient’s hand with one hand, and with the other hand grasp the thumb metacarpal. Axially compress the CMC joint while rotating the metacarpal around its long axis and/or circumducting it.
Positive results:
- Pt. reports pain and/or crepitus (at CMC joint) with this maneuver
Negative Results:
- No change in pain
Implications of positive test result:
- Thumb CMC joint OA
In my experience this test is more specific than it is sensitive (a positive result is fairly reliable, while a negative result does not mean much of anything).