This contrasts with conditions such as shoulder impingement syndrome or rotator cuff tendinitis in which the active range of motion is restricted but passive range of motion is normal. Some exam maneuvers of the shoulder may be impossible due to pain. Causes
The causes of adhesive capsulitis are incompletely understood; however, there are several factors associated with higher risk. Risk factors for secondary adhesive capsulitis include injury or surgery leading to prolonged immobility. Risk factors for primary, or idiopathic adhesive capsulitis include many systemic diseases, such as diabetes mellitus, stroke, lung disease, connective tissue diseases, thyroid disease, heart disease, autoimmune disease, and Dupuytrens contracture. Both type 1 diabetes and type 2 diabetes are risk factors for the condition. Primary
Primary adhesive capsulitis, also known as idiopathic adhesive capsulitis, occurs with no known trigger. It is more likely to develop in the non-dominant arm. Secondary
Adhesive capsulitis is called secondary when it develops after an injury or surgery to the shoulder. Pathophysiology
The underlying pathophysiology is incompletely understood, but is generally accepted to have both inflammatory and fibrotic components. The hardening of the shoulder joint capsule is central to the disease process. This is the result of scar tissue (adhesions) around the joint capsule. There also may be a reduction in synovial fluid, which normally helps the shoulder joint, a ball and socket joint, move by lubricating the gap between the humerus and the socket in the shoulder blade. In the painful stage (stage I), there is evidence of inflammatory cytokines in the joint fluid.
Pain and stiffness may not completely resolve in 20 to 50 per cent of affected people. Epidemiology
Adhesive capsulitis newly affects approximately 0.75% to 5.0% percent of people a year. Rates are higher in people with diabetes (10–46%). Following breast surgery, some known complications include loss of shoulder range of motion (ROM) and reduced functional mobility in the involved arm. Occurrence is rare in children and people under 40. with the highest prevalence between 40 and 70 years of age. The condition is more common in women than in men (70% of patients are women aged 40–60). People with diabetes, stroke, lung disease, rheumatoid arthritis, or heart disease are at a higher risk for frozen shoulder. Symptoms in people with diabetes may be more protracted than in the non-diabetic population. See also
Calcific tendinitis
Milwaukee shoulder syndrome

References


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