The Lift-off Sign primarily evaluates function of which rotator cuff muscle?

• A. Subscapularis
• B. Supraspinatus
• C. Infraspinatus
• D. Teres Minor

Answer: (A)

The Lift-off Sign tests the subscapularis muscle because the maneuver requires internal rotation and pulling the hand away from the back against resistance, which is the primary action of the subscapularis. When the hand is placed on the back, the subscapularis contracts to rotate the humerus inward and to keep the humeral head centered in the glenoid. If the subscapularis is torn or weak, the patient can’t lift the hand off the back or maintain the position against pressure, producing a positive sign. Other rotator cuff muscles are responsible for different actions—supraspinatus for initiating abduction, infraspinatus and teres minor for external rotation—so they aren’t isolated by this test.