The clinical significance of the valve mechanism in communicating popliteal cysts.

In a previous investigation of 41 patients presenting with distended popliteal cysts, a valvular mechanism was demonstrated in 25 cases by means of a specific arthrographic procedure. In the present study the clinical symptoms and signs from the popliteal space and from the joint were assessed and related to the presence or absence of a valvular mechanism. By arthroscopy or arthrotomy seventeen associated knee disorders were diagnosed, e.g., synovitis, osteoarthritis, and tears of a semilunar cartilage. Intraarticular symptoms and intrinsic joint diseases were significantly correlated to the absence of a valve mechanism. The presence of a valve mechanism was indicative of the absence of pathological findings in the joint.