If pain is present in both pronated and supinated positions during O’Brien's test, what is the most likely interpretation?

If pain is present in both pronated and supinated positions during O’Brien's test, what is the most likely interpretation?

• A. AC joint pathology (false positive)
• B. SLAP tear
• C. Biceps tendinopathy
• D. Glenoid labrum tear

Answer: (A)

O’Brien’s test is used to tell whether shoulder pain comes from a SLAP lesion or from the AC joint by changing the forearm position. In a SLAP lesion, the pain is typically elicited when the forearm is pronated and then relieved when the forearm is supinated, because supination reduces the biceps-labrum tension that helps provoke the labral pain. If pain occurs in both pronated and supinated positions, the issue is less about the labrum and more about the AC joint, which tends to be irritated regardless of forearm rotation. This pattern is why AC joint pathology is the most likely interpretation here, and why such a finding can be a false positive for a SLAP test.

O’Brien’s test is used to tell whether shoulder pain comes from a SLAP lesion or from the AC joint by changing the forearm position. In a SLAP lesion, the pain is typically elicited when the forearm is pronated and then relieved when the forearm is supinated, because supination reduces the biceps-labrum tension that helps provoke the labral pain. If pain occurs in both pronated and supinated positions, the issue is less about the labrum and more about the AC joint, which tends to be irritated regardless of forearm rotation. This pattern is why AC joint pathology is the most likely interpretation here, and why such a finding can be a false positive for a SLAP test.