Execution
- 1Hold the patient’s hand with one hand.
- 2Grasp the patient’s thumb below the metacarpophalangeal joint with the other hand.
- 3Apply axial compression along the first metacarpal.
- 4Rotate the thumb metacarpal while compression is maintained.
- 5Record pain, crepitus, and whether symptoms localize to the thumb base.
Positive outcome
Pain or crepitus at the thumb base during axial compression and rotation is positive. Magee states that the test indicates degenerative joint disease in the metacarpophalangeal or metacarpotrapezial joint. Localizing pain to the CMC joint improves interpretation.
Studies
| Study | Reliability | Sn | Sp | LR+ | LR− |
|---|---|---|---|---|---|
| Merritt et al. (2010) | κ = 0.48 | 42-53 | 80-93 | 2.65-6.00 | 0.59-0.62 |
| Choa et al. (2014) | NA | 30 | 96.7 | 9.09 | 0.72 |
| Sela et al. (2019) | NA | 64 | 100 | infinity | 0.36 |
CommentThe grind test is traditional but not consistently sensitive. Merritt reported moderate reliability, and Choa found the traction-shift test more sensitive and more specific. A positive grind can support CMC OA, but a negative test does not rule it out.
High Clinical Value