During the sulcus sign, what finding is positive?

• A. A gap of one finger width or more at the shoulder line
• B. Pain on abduction
• C. Increased external rotation
• D. Joint line tenderness

Answer: (A)

The sulcus sign tests inferior shoulder laxity by looking for an indentation below the acromion when the arm is gently pulled downward. If the joint capsule and ligaments are lax, the humeral head can be displaced downward, creating a visible sulcus. A positive finding is a gap about a finger’s width (roughly 1 cm) or more at the shoulder line, indicating inferior instability or multidirectional laxity.

Pain on abduction would suggest impingement or rotator cuff/labral issues, not the laxity this test measures. Increased external rotation points to instability in a different plane (often anterior) and isn’t the defining feature of the sulcus sign. Joint line tenderness indicates other intra-articular pathology rather than inferior capsular laxity.