The popliteus as a retractor of the lateral meniscus of the knee.

Because of inconsistencies in the literature regarding popliteus and its relation to the lateral meniscus, it was decided to investigate the influence on the behavior of the lateral meniscus of contraction of the popliteus muscle via arthroscopy. A series of 50 knees from 44 patients who underwent elective arthroscopic surgery were examined. During arthroscopy, popliteus was stimulated to contract using surface electrodes. Any resultant meniscal retraction was observed and recorded. Thirty-one knees showed such retraction, and no retraction was observed in the remaining 19 knees. The clinical implications of this study are limited, but the results may support a number of proposed theories. It may be concluded that in a population exhibiting normal, intact lateral menisci, popliteus variably acts as a retractor of the lateral meniscus.