Adhesive Capsulitis in Physical Medicine and Rehabilitation

most commonly referred to as frozen shoulder (FS), is an idiopathic disease with 2 principal characteristics: pain and contracture.

Pain

Shoulder pain associated with FS is progressive and initially felt mostly at night or when the shoulder is moved close to the end of its range of motion (ROM). It can be caused by certain combined movements of the shoulder, such as abduction and external rotation (eg, grooming one's hair, reaching for a seatbelt overhead) or extension and internal rotation (eg, reaching for a back pocket or bra strap). The pain usually progresses to constant pain at rest that is aggravated by all movements of the shoulder and that may be worsened by repetitive movements of the involved upper extremity, psychological stress, exposure to cold or vibration, and changes in the weather. In approximately 90% of patients with FS, this pain usually lasts 1-2 years before subsiding.^[1]

Contracture

The second principal characteristic of FS is progressive loss of passive ROM (PROM) and active ROM (AROM) of the  in a capsular pattern. That is, the movements are usually restricted to a characteristic pattern, with proportionally greater passive loss of external rotation than of abduction and internal rotation.
In 1934, Codman stated, "This entity [FS] is difficult to define, difficult to treat, and difficult to explain from the point of view of pathology." Codman's statement continues to hold true today.
In 1992, the American Shoulder and Elbow Surgeons Society agreed on the following definition of FS by consensus: a condition of uncertain etiology that is characterized by clinically significant restriction of active and passive shoulder motion that occurs in the absence of a known intrinsic shoulder disorder