Sulcus sign

This maneuver is used to assess glenohumoral instability. The patient is asked to relax the shoulder. One hand is placed at the acromion and one hand is placed near the antecubital fossa. Downward pressure is applied to the arm to open the subacromial space. The examiner assesses the looseness of the shoulder and the discomfort caused by the maneuver. The sulcus sign is positive when the humeral head (X) is readily displaced by 2 cm or more inferiorly (arrow). Increased humoral movement in the anterior and posterior directions demonstrates multidirectional instability.