Frozen shoulder, also known as adhesive capsulitis, causes pain and stiffness in the shoulder. It is caused by a thickening of the capsule surrounding the shoulder joint. The exact cause of frozen shoulder in not known, but it is associated with risk factors such as prolonged immobilization (typically after an injury or surgery), diabetes, thyroid disorders, Parkinson’s disease, and cardiac disease. Imaging such as X-rays and MRIs of the shoulder are considered to rule other potential causes of the shoulder pain and reduced range of motion such as a rotator cuff tear or arthritis.
The overwhelming majority of patients improve with conservative care, which includes a physical therapy program and anti-inflammatory medications. However, the improvement is typically gradual and can take up to 2-3 years. Cortisone injections for the shoulder at times are performed but in general are not helpful. Surgery may be considered in patients who do not improve with more conservative care. Manipulation under anesthesia is a procedure in which a surgeon manipulates and stretches the shoulder joint capsule and scar tissue under general anesthesia to improve the shoulder’s motion. Shoulder arthroscopy is performed to release portions of the capsule that are “frozen”.