AnatoMemory

Muscle

Popliteus

"Unlocks" the knee

Lower limbMuscular system

High-yield

Unlocks the knee by rotating the femur laterally on the tibia (medially rotating the tibia when non-weight-bearing). Tibial nerve.

Overview

A deep muscle of the popliteal fossa floor that laterally rotates the femur on the fixed tibia to unlock the fully extended knee for flexion.

Reference facts

Origin
Lateral condyle of the femur and lateral meniscus
Insertion
Posterior surface of the proximal tibia (above the soleal line)
Action
Unlocks the extended knee; medially rotates the tibia (or laterally rotates the femur when weight-bearing)
Innervation
Tibial nerve (L4, L5, S1)
Blood supply
Popliteal / posterior tibial arteries

Frequently asked questions

What does the popliteus do?

The popliteus unlocks the extended knee; medially rotates the tibia (or laterally rotates the femur when weight-bearing).

What nerve innervates the popliteus?

The popliteus is innervated by the tibial nerve (L4, L5, S1).

Where does the popliteus attach?

The popliteus originates from the lateral condyle of the femur and lateral meniscus and inserts on the posterior surface of the proximal tibia (above the soleal line).

What is the blood supply of the popliteus?

The popliteus is supplied by the popliteal / posterior tibial arteries.