Case report 707: Hemorrhagic Baker's cyst of the right calf.

A 50-year-old woman with juvenile rheumatoid arthritis presented with painful swelling of the right calf. Roentgenograms, sonograms, magnetic resonance images, and arthrograms were obtained. A diagnosis of hemorrhagic Baker's cyst was made, and surgical excision was performed. The etiology, clinical features, and radiological evaluation of simple and complicated Baker's cysts are discussed and the differential diagnosis considered.