Apatite deposition in polymyositis subluxing arthropathy.

We describe a 47-year-old woman who developed chronic subluxing arthropathy associated with polymyositis (PM) and positive anti-Jo1 antibodies. After a followup of 3 years, PM did not recur and polyarthritis dominated her clinical picture, leading to deformities and periarticular calcifications in her hands, shoulders, and feet. Patients with myositis, anti-Jot antibodies, and periarticular calcifications are at risk of developing deforming arthritis unresponsive to conventional therapy.