Question

The lift-off test is done to assess the function of:

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

Hint:

Lifting the hand off the back needs internal rotation, the job of the subscapularis.

Answer 1

The Correct Option is D

Step 1: Recall the rotator cuff and its actions. The four cuff muscles are supraspinatus (abduction initiation), infraspinatus and teres minor (external rotation), and subscapularis (internal rotation of the shoulder).

Step 2: Recall how the lift-off test is performed. The patient places the dorsum of the hand on the lower back and then tries to lift the hand away from the back. Lifting the hand off the back requires internal rotation of the arm.

Step 3: Link the action to the muscle. Internal rotation of the shoulder is the job of the subscapularis. If the subscapularis is torn or weak, the patient cannot lift the hand off the back, giving a positive lift-off test.

Step 4: Exclude the distractors. Supraspinatus is tested by the empty-can (Jobe) test. Infraspinatus and teres minor are tested by resisted external rotation, the opposite movement to the lift-off test.

Step 5: The lift-off test specifically evaluates internal rotation, so the answer is Subscapularis (option D).