Major Tom is having difficulty abducting his right arm through 90 degrees; which test would provide the most clinically relevant information?

Major Tom is having difficulty abducting his right arm through 90 degrees; which test would provide the most clinically relevant information?

• A. Maximum elbow flexion
• B. Empty can test
• C. Noble
• D. Valgus overload

Answer: (B)

Initiation of arm abduction mainly relies on the supraspinatus. When there’s pathology in that tendon, you often see weakness or pain as you try to initiate or move the arm into abduction, even up to 90 degrees. The empty can test isolates the supraspinatus by having the arm placed in the scapular plane with the shoulder internally rotated (thumbs down) and then asking the patient to hold that position against downward pressure. A positive result—pain or weakness—points to supraspinatus tendinopathy or tear, which would directly explain difficulty abducting through 90 degrees. The other tests don’t target the shoulder rotator cuff in the same way: maximum elbow flexion assesses the elbow, not the shoulder; Noble tests the knee/IT band; and valgus overload stresses the elbow ligaments.

Initiation of arm abduction mainly relies on the supraspinatus. When there’s pathology in that tendon, you often see weakness or pain as you try to initiate or move the arm into abduction, even up to 90 degrees.

The empty can test isolates the supraspinatus by having the arm placed in the scapular plane with the shoulder internally rotated (thumbs down) and then asking the patient to hold that position against downward pressure. A positive result—pain or weakness—points to supraspinatus tendinopathy or tear, which would directly explain difficulty abducting through 90 degrees.

The other tests don’t target the shoulder rotator cuff in the same way: maximum elbow flexion assesses the elbow, not the shoulder; Noble tests the knee/IT band; and valgus overload stresses the elbow ligaments.