Suprapatellar plicae of the knee presenting as a soft-tissue mass. Report of five patients.

It is well recognized that synovial plicae can lead to clinical manifestations that simulate internal derangements of the knee, meniscal tears, or arthritis. Such plicae, however, also can lead to compartmentalization of the joint. We report on five patients with abnormal suprapatellar plicae that led to joint compartmentalization and distention of the suprapatellar bursa manifested as a soft-tissue mass.