Adhesive capsulitis or frozen shoulder is an idiopathic (no known cause) condition that involves the joint lining (synovium and capsule) of the shoulder joint. Most patients are in their late 30’s to mid 40’s and the condition is more common in women than men. Patients initially complain of relatively persistent aching in the joint accompanied by loss of range of motion. Unlike bursitis or rotator cuff tears, which are also common conditions in the shoulder, strength is relatively well preserved but motion, especially rotation, is lost. The condition runs a prolonged clinical course from 5-18 months but most patients eventually regain most of their original range of motion and function. Treatment is non-operative with physical therapy and anti-inflammatory medication. Surgery is rarely indicated and often compounds the problem. Unfortunately, many patients (40%) will develop the same condition in the opposite shoulder within 2 years.