Synovial osteochondromatosis mimicking juvenile idiopathic arthritis in an adolescent: a case-based review.

Synovial osteochondromatosis is an extremely rare benign condition in children and adolescents that have joint pain as a presenting manifestation. It is usually monoarticular with the knee as the most common affected joint. In this article, we describe the case of a female adolescent suffering from debilitating chronic right knee pain initially mimicking juvenile idiopathic arthritis, who was subsequently diagnosed with primary synovial osteochondromatosis.