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Poplitaeus Muscle, Subpoplitaeus, (F.) Muscle poplite, Muscle Jarretier, Femoro-popliti-tibial, (Ch.), is seated in the popliteal region. It is triangular, long, flat; and is inserted, on the one hand, by means of a strong tendon, into the tuberosity at the outer condyle of the femur, terminating below at the upper part of the posterior surface of the tibia. This muscle bends the leg on the thigh, and, reciprocally, the thigh on the leg. When the leg is bent, it causes it to turn, in rotation, inwards.