- Sulcus Sign is used to test for Multidirectional Instability (MDI)
- have the patient stand relaxed with their arms at their side.
- Grab their affected arm and pull it inferiorly.
- If there is a sulcus that forms at the superior aspect of the humeral head, the test is positive.
- Sulcus is considered positive if it stays increased (2+ or 3+) with ER at side (pathologic rotator interval)
- Sensitivity: 28 %
- Specificity: 97 %