Nontraumatic osteomyelitis of the patella.

Nontraumatic, hemotogenous osteomyelitis is a childhood disease uncommonly encountered and rare in the patella. The initial signs are usually intraarticular, because of the sterile effusion. The primary pathology in the patella is easy to overlook. The infection generally does not penetrate the joint cavity and most cases can be treated conservatively, or by local debridement. Arthrotomy is not necessary and could involve the joint with the infection.