Execution
- 1Position the patient prone.
- 2Abduct the arm to approximately 120° with the shoulder externally rotated.
- 3Ask the patient to move into diagonal extension.
- 4Apply resistance to the diagonal extension movement.
- 5Observe for normal scapular retraction versus scapular protraction or substitution.
Positive outcome
Scapular protraction during resisted diagonal extension indicates lower trapezius weakness. Inability to hold the position may also suggest weakness, but pain inhibition and limited shoulder elevation must be considered.
Studies
| Study | Reliability | Sn | Sp | LR+ | LR− |
|---|---|---|---|---|---|
| Brunnstrom (1941) | NA | NA | NA | NA | NA |
CommentThis is a manual muscle test for lower trapezius function and scapular control. It is not a diagnostic test for a specific shoulder lesion. It is best paired with observation of scapular upward rotation, posterior tilt, and thoracic compensation during arm elevation.