Adhesive Capsulitis
Introduction and prevalence
Adhesive capsulitis, also known as frozen shoulder, is a common cause of shoulder pain and decrease in range of motion, especially in the external rotation. The prevalence of adhesive capsulitis is estimated at 2% to 5% of the general population, with most patient being middle-aged women. The condition is associated with diabetes and hypothyroidism. Interestingly, the non-dominant hand is often affected.
Etiology and Pathophysiology
Primary adhesive capsulitis is usually idiopathic and has a gradual onset. It can also be associated with underlying conditions such as diabetes mellitus, thyroid disease, hypertriglyceridemia, or cervical spondylosis. Secondary adhesive capsulitis can be a result of trauma, rotator cuff injuries, surgery, or prolonged immobilization. Adhesive capsulitis results in gradual loss of glenohumeral motion from progressive fibrosis and contracture of the glenohumeral joint capsule.
Clinical presentation
Poorly localized dull shoulder pain that radiates to biceps, accompanied by a decrease in passive and active range of shoulder motion, especially the external rotation, defines a typical presentation of adhesive capsulitis. Reaching overhead or behind the back may worsen symptoms.
Physical examination
The key clinical sign of adhesive capsulitis is a reduction in active and passive ROM in forward flexion, abduction, and external and internal rotation. The palpation of the affected shoulder joint may reveal diffuse tenderness and the distal neurological examination should be within normal. Neer and Hawkins tests for impingement can be positive in adhesive capsulitis.
Investigations
HbA1C, TSH should be ordered if there are any suspicions of diabetes or hypothyroidism. Radiography is useful in ruling out glenohumeral arthritis, fractures, avascular necrosis, and calcific rotator cuff tendinopathy. MRI may reveal findings suggestive of adhesive capsulitis, including rotator interval synovitis, hypertrophy of the coracohumeral ligament, loss of the subcoracoid fat triangle, and thickness of the glenohumeral joint capsule throughout the axillary pouch.
Management
In most cases, adhesive capsulitis is self limiting within 18-30 months. Therapies are aimed at symptoms management and speeding recovery. These treatments include NSAID, short-term oral steroid, intra-articular steroid injection, gentle physical therapy (including gentle ROM exercises, stretching, and graded resistance training), hydro-dilatation of the glenohumeral capsule, suprascapular nerve block, arthroscopic capsular release, and open capsular release.