Adhesive capsulitis of the shoulder

Adhesive capsulitis of the shoulder (also known as frozen shoulder) is a condition characterised by thickening and contraction of the shoulder joint capsule and surrounding synovium.

Epidemiology

Adhesive capsulitis is divided into two main types: 

1. primary or idiopathic 
2. secondary 

Primary or idiopathic adhesive capsulitis refers to patients who develop the condition in the absence of preceding trauma. 

Secondary adhesive capsulitis, on the other hand, may result from a number of antecedent conditions, including:

• major or minor repetitive trauma
• surgery
• endocrine (e.g. diabetes) or rheumatological conditions. 

Adhesive capsulitis typically affects women in the 5^th to 6^th decades of life, although patients with co-morbidities such as diabetes may develop the condition at earlier ages. The incidence in patients with diabetes is reported to be 2 to 4 times higher than in the general population.

Radiographic features

Fluroscopic arthrography

Described features include

• limited injectable fluid capacity of the glenohumeral joint 
• a small dependent axillary fold
• irregularity of the anterior capsular insertion at the anatomic neck of the humerus

MRI / MR arthrography

The normal inferior glenohumeral ligament measures < 4 mm and is best seen on coronal oblique images at the mid glenoid level. In adhesive capsulitis, the axillary recess may show thickening up to 1.3 cm or more. The joint capsule is also thickened ².

Other MR arthrographic features include

• thickening of the coraco-humeral ligament (CHL) ⁴
• sub-coracoid triangle sign ⁴

Treatment and prognosis

Adhesive capsulitis is typically a self-limiting disease that improves over 1 - 2 years. Treatment options include:

• physiotherapy
• corticosteroid injections / hydrodilatation
• closed manipulation under anesthesia
• arthroscopic capsular release with lysis of adhesions