Execution
- 1Position the patient sitting with the arm internally rotated and forward flexed to 90°.
- 2Grasp the elbow and applies an axial load proximally through the humerus.
- 3Maintain axial loading while horizontally adducting the arm across the body.
- 4Feel for a sudden posterior subluxation jerk or clunk.
- 5Return the arm toward the starting position and note whether a second jerk occurs as the humeral head reduces.
Positive outcome
A sudden jerk or clunk as the humeral head subluxes posteriorly is positive. Painful jerk / clicking may also indicate a posteroinferior labral lesion.
Studies
| Study | Reliability | Sn | Sp | LR+ | LR− |
|---|---|---|---|---|---|
| Kim et al. (2005) | NA | 73 | 98 | 36.5 | 0.28 |
CommentThe jerk test is a strong rule-in test when a true jerk / clunk reproduces the patient’s symptoms. It can be uncomfortable and should be performed with control. In posterior shoulder pain without instability symptoms, combine with Kim’s test and history before concluding posteroinferior labral tear.
High Clinical Value