Popliteal cyst rupture in normal knee joints

Abstract

Rupture of popliteal cysts is a well-recognised cause of pain and swelling in the calf. Confusion may arise because the symptoms and signs resemble those produced by a deep venous thrombosis. 123 The important differentiating factor is evidence of joint disease, so that a diagnosis of popliteal cyst rupture is unlikely to be considered in patients with healthy knee joints. We report on six patients in whom rupture of a popliteal cyst appears to have caused pain and swelling in the calf in the absence of underlying disease of the knee joint. Because this was thought not to occur, deep venous thrombosis of the calf was erroneously diagnosed. © 1980, British Medical Journal Publishing Group. All rights reserved.