Rheumatoid arthritis is the most common idiopathic inflammatory arthritis, affecting approximately 0.8% of the population, and it is two to four times more common in women than in men. The disease is characterized by hypertrophic synovitis that leads to joint laxity from soft-tissue attenuation, which may lead to joint subluxation and dislocation. Joint cartilage destruction usually ensues and may lead to attritional tendon rupture. However, isolated nodular tendon involvement may exist independent of overt joint pathology, leading to joint motion limitation, such as triggering or locking of flexor tendons. Similarly, extensor tendon nodularity may limit wrist extension from impingement on the extensor retinaculum. Despite preservation of function, socialization sometimes is altered by disfiguring deformities, especially of the hands.
