Shoulder Impingement Syndrome (SIS): Signs and Symptoms Repetitive Overhead Activity, Scapular Dyskinesis -> Scapulohumeral mechanics become altered -> Narrowing of subacromial space -> Impingement of subacromial bursa, Impingement of underlying rotator cuff (RC) muscle-tendon unit -> Shoulder Impingement Syndrome + Painful arc test - Pain at 60-120 with passive shoulder abduction + Neer's sign - Passive flexion of the shoulder while stabilizing the scapula reproduces the pain + Hawkin's test - Forward flexion of the shoulder to 90, followed by passive internal rotation reproduces pain #Shoulder #Impingement #Syndrome #SIS #diagnosis #signs #symptoms #msk #pathophysiology
