Deep layer of muscles on the back of the leg (popliteus visible at center top)
|Origin||Posterior-lateral surface of femur below the lateral epicondyle|
|Insertion||Medial surface of the proximal tibia below the medial condyle|
|Actions||Medial rotation and flexion of knee|
|Anatomical terms of muscle|
The popliteus muscle in the leg is used for unlocking the knees while walking by medially rotating the tibia during the closed chain portion of the gait cycle (one with the foot in contact with the ground).
Peroneotibialis, 14% of population. Origin is inner side of the head of the fibula, insertion into the upper end of the oblique line of the tibia, it lies beneath the popliteus.
Another variant the cyamella is a small sesamoid bone embedded in the tendon of the popliteus muscle. It is rarely seen in humans, but has been described more often in other primates and certain other animals.
The popliteus assists in flexing the leg upon the thigh; when the leg is flexed, it will rotate the tibia inward.
It is especially called into action at the beginning of the act of bending the knee, in as much as it produces the slight inward rotation of the tibia, which is essential in the early stage of this movement.
When the knee is in full extension; the femur slightly medially rotates on the tibia to lock the knee joint in place. Popliteus is often referred to as the "Key" to unlocking the knee since it begins knee flexion by laterally rotating the femur on the tibia.
Popliteus is also attached to the lateral meniscus in the knee; and draws it posteriorly during knee flexion to prevent crushing the meniscus between the tibia and femur as the knee flexes.
A popliteus shortened by trigger points can cause pain near its tendinous origin at the lateral knee.
- This article uses anatomical terminology; for an overview, see anatomical terminology.
|Wikimedia Commons has media related to Popliteus muscle.|
- Origin, insertion and nerve supply of the muscle at Loyola University Chicago Stritch School of Medicine
- 93978702 at GPnotebook
- Anatomy photo:15:st-0413 at the SUNY Downstate Medical Center
- popliteus+%28muscle%29 at eMedicine Dictionary