Definition of Frozen shoulder:

Frozen shoulder is the common term for adhesive capsulitis, an inflammatory condition that restricts motion in the shoulder.

Causes, incidence, and risk factors:

The capsule of a shoulder joint includes the ligaments that attach the shoulder bones to each other. When inflammation occurs within the capsule, the shoulder bones are unable to freely move within the joint.

Diabetes, shoulder trauma (including surgery), a history of open heart surgery, hyperthyroidism, and a history of cervical disk disease are all associated with an increased risk for this problem. Often, there is no known cause.