The proximal attachments of the popliteus muscle: a quantitative study and clinical significance

Controversies about the existence of accessory proximal popliteus muscle attachments can be found in the literature. The aim of this study was to verify the occurrence and width of popliteus attachments on the articular and periarticular structures of the knee joint. The relation of these attachments to tibiofemoral cartilage and meniscus degeneration was also investigated. Forty-two anatomical specimens were dissected. The incidence of accessory proximal attachments was determined and their width measured using a caliper. The fibular attachment of the popliteus was observed in 98% of cases; its mean width was 11 (SD 3) mm. At least one attachment on the lateral meniscus was found in 95% of the specimens, with a mean width of 6 (SD 2) mm. Three types of meniscal attachments of the popliteus could be identified. The severity of meniscus and tibiofemoral cartilage alterations was significantly related to the number of meniscopopliteal fascicles: more severe alterations were seen in knees with fewer meniscopopliteal fascicles. Popliteus attachments on the posterior knee joint capsule (57%), arcuate (90%) and oblique popliteal (79%) ligaments were also observed in most specimens. Popliteus muscle relationships with the posterior cruciate (5%) and meniscofemoral (33%) ligament were less common. In conclusion, accessory popliteus attachments on the fibula, lateral meniscus and arcuate popliteal ligament can be considered constant characteristics. The results of this study suggest a role of the popliteus in the protection of knee menisci and tibiofemoral cartilage.