13/02/2026
Understanding the Shoulder Painful Arc Test (Impingement Arc)
The shoulder painful arc test is a simple but clinically powerful screening method used to identify possible subacromial impingement or rotator cuff involvement. During this test, the examiner or patient actively raises the arm sideways into abduction from 0° to full elevation. What makes this test valuable is not just whether pain is present — but where in the range the pain appears.
In a typical positive painful arc pattern, discomfort occurs between approximately 60° and 120° of shoulder abduction. This mid-range zone corresponds to the position where the rotator cuff tendons — especially the supraspinatus — and the subacromial bursa pass beneath the acromion. If these tissues are inflamed, thickened, or compressed, this portion of movement produces a sharp or catching pain.
Interestingly, patients often report less or no pain below 60° and above 120°. Below 60°, the structures are not yet significantly compressed. Above 120°, the humeral head and acromion relationship changes and the compressed tissues may clear the tightest space, temporarily reducing symptoms. This pattern helps clinicians differentiate impingement from other shoulder pathologies.
From a rehab and biomechanics perspective, a positive painful arc highlights the importance of scapular control, rotator cuff strength, posture correction, and load management. Treatment is not just about reducing pain — it’s about restoring proper shoulder mechanics so the subacromial space is protected during movement.
Always combine this test with other clinical findings and functional assessment for accurate diagnosis and targeted rehabilitation.
