Insufficiency fractures of the knee, ankle, and foot in rheumatoid arthritis: A case series and case-control study.

Insufficiency fractures of the knee, ankle, and foot are a significant cause of pain and long-lasting disability in RA. Recurrent fractures are common. Diagnosis is often delayed and confused with arthritic activity. Conventional radiography and DEXA scan are often normal. Older age, female gender, radiological erosions in hand/wrist, and treatment with methotrexate were all significantly associated with fractures.