It is a chronic progressive inflammatory polyarthritis of autoimmune origin that affects the synovial joints. It differs from osteoarthritis because it initially affects the synovial membrane and not the cartilage, it occurs less frequently and in younger individuals compared to osteoarthritis. Women are more affected (3:1 ratio). It affects 1-2% of the population.

The onset is typically observed at the end of adolescence or between the 4th and 5th decade of life; a second peak is observed between the ages of 60 and 70.

Osteoarthritic pathology is manifested by the wear and gradual resorption of the articular cartilage, reduction of the joint space, abnormal bone production (osteophytes), deformation of the joint surfaces, thickening of the capsule with the formation of calcifications. This results in acute pain and significant limitation in movement. Diagnosis is relatively simple based on symptoms and an X-ray examination.

Therapy is generally planned according to the stage of progression. The most effective treatment is often surgical (shoulder arthroplasty), with the replacement of the affected joint surfaces.

The goal of total shoulder arthroplasty is to reduce pain, recover lost mobility, and improve the patient’s quality of life.

There are two different configurations of shoulder prostheses: “anatomical” and “reverse,” both typically made of 3 components composed of highly biocompatible materials. The reverse configuration is generally indicated for conditions affecting the rotator cuff. The fixation of the prosthesis to the bone can be either without the use of cement (biological fixation) or with cement.

Pharmacological therapies, physical therapy, corticosteroid injections, or other measures can temporarily relieve pain but do not provide a definitive solution.