Definition

Primary adhesive capsulitis of the shoulder is an idiopathic, progressive, painful but self-limited restriction of active and passive range of motion [1–3]. The onset is insidious and progresses through several stages, usually during the course of 1 to 2 years. These stages include the painful phase, the freezing or adhesive phase, and the thawing or resolution phase. Adhesive capsulitis occurs in approximately 2% to 5% of the general population and accounts for approximately 6% of office visits to shoulder specialists (orthopedists and physiatrists) on a yearly basis [2]. The condition preferentially affects women after the age of 50 years, involves the nondominant shoulder, and develops in the opposite shoulder in 20% to 30% of cases. The primary etiology is unknown, but it is associated with numerous secondary causes, including immobilization, diabetes, hypothyroidism, autoimmune disease, and treatment of breast cancer (Table 11.1).

The pathologic process related to adhesive capsulitis involves structures both intrinsic to the glenohumeral joint and surrounding it (Fig. 11.1). Although it is not clear, one theory is that stimulation of synovitis leads to fibrosis due to the activation of various cytokines, including growth factors such as transforming growth factor-β [4]. The pathologic findings of adhesive capsulitis ultimately depend on its stage when it is assessed [1,2]. The painful phase is characterized by synovitis that progresses to capsular thickening (particularly in the anterior and inferior portions of the capsule) with an associated reduction in synovial fluid. As the adhesive phase continues, fibrosis of the capsule is more pronounced, and thickening of the rotator cuff tendons is common. As this phase continues, the glenohumeral joint space becomes contracted and often obliterated. Pathologic change is more consistent with chronic inflammation with resolution of joint space loss during the final stage.

Symptoms

Symptoms will depend on the stage of adhesive capsulitis. In stage 1, the patients experience the gradual onset of progressive pain that is worse during the night and exacerbated by overhead activities. They will gradually report a loss of motion with symptoms lasting less than 3 months. In stage 2, there is a progressive increase in pain that is associated with a reduction in the range of motion and decreased use of the affected shoulder [1,2]. The stage can last 9 to 15 months. Stage 3, the “thawing stage,” is characterized by a gradual decrease in pain and increase in the pain-free range of motion. Some individuals will return to normal, but not all (Table 11.2).

Physical Examination

The findings noted on physical examination reflect the stage of adhesive capsulitis development. During the painful and adhesive stages of adhesive capsulitis, there is a measurable reduction in both passive and active shoulder range of motion. Motion is painful, particularly at the extremes of external rotation and abduction [1,2,5]. This pattern of motion loss is consistent with a capsular pattern of passive range of motion loss, which demonstrates a greater limitation in external rotation and abduction followed by an increasing loss of flexion. These signs are similar to those found in osteoarthritis of the glenohumeral joint, in which there is a similar loss of motion with shoulder pain. However, this presentation is in contrast to findings seen in rotator cuff tears, in which active range of motion is restricted but passive range of motion may approximate normal values. A reduced glenohumeral glide is often noted with adhesive capsulitis, especially with inferior translation. The relationship of glenohumeral joint movements independent of scapulothoracic motion should also be noted. Last, the shoulder is often painful to palpation around the rotator cuff tendons distally. As symptoms start to improve and the patient enters the resolution stage, there is a reversal of the loss of motion, with internal rotation being the last to improve.