Capsulitis is the inflammation of the joint capsule, the fibrous structure that surrounds and stabilizes a joint, often accompanied by involvement of the synovial membrane that lines the inner surface of the capsule. It is commonly caused by repetitive mechanical stress, trauma, prolonged joint immobilization, or systemic inflammatory conditions such as rheumatoid arthritis.
A typical example is frozen shoulder (adhesive capsulitis), in which chronic inflammation of the shoulder capsule gradually leads to fibrosis and contraction of the capsule, resulting in a significant restriction of the joint’s range of motion.
The main symptoms include pain, local swelling, a sensation of warmth in the affected area, and progressively increasing stiffness, which may significantly interfere with the patient’s daily activities and functional independence. Diagnosis is based on clinical examination, including assessment of pain and range of motion, while imaging studies such as magnetic resonance imaging (MRI) may be used to support the diagnosis and exclude other conditions.
Treatment includes physical therapy with targeted mobilization exercises, medication to control pain and inflammation, and intra-articular corticosteroid injections in persistent cases. In rare situations, surgical intervention may be required to release the contracted joint capsule and restore mobility.