This article reviews 41 cases of the popliteal artery entrapment syndrome in individuals less than 20 years of age. In this syndrome, symptoms are caused by vascular insufficiency produced by either an anomalous course of the popliteal artery or anomalous muscles impinging upon it. Because vascular insufficiency is uncommon in orthopedic patients in this age group and this syndrome has received little attention in the orthopedic literature, orthopedists unfamiliar with this relatively easily diagnosed condition may miss it.