Muscle
Rectus femoris
Quadriceps muscle acting at both hip and knee
High-yield
Among the four conventionally named quadriceps components, it crosses both hip and knee. Hip position therefore changes its length even when the knee stays still, affecting how it contributes to movement.
Overview
Rectus femoris begins on the pelvis and lies over the deeper quadriceps muscles. It reaches the patella through their shared tendon system, giving it a role in lifting the thigh as well as straightening the knee.
Reference facts
- Origin
- Direct head from the anterior inferior iliac spine; reflected head from the supraacetabular region and adjacent hip capsule
- Insertion
- Patella through the quadriceps tendon, with force transmitted by the patellar ligament to the tibial tuberosity
- Action
- Extends the knee and assists hip flexion
- Innervation
- Femoral nerve muscular branches, conventionally L2-L4
- Blood supply
- Mainly lateral circumflex femoral branches, with other profunda femoris/femoral contributions
Clinical correlation
A forceful pull in a growing athlete can avulse the anterior inferior iliac spine at the direct-head attachment. The two proximal tendons and nearby structures help explain why the exact injury site matters.
Frequently asked questions
What does the rectus femoris do?
The rectus femoris extends the knee and assists hip flexion.
What nerve innervates the rectus femoris?
The rectus femoris is innervated by the femoral nerve muscular branches, conventionally L2-L4.
Where does the rectus femoris attach?
Origin: Direct head from the anterior inferior iliac spine; reflected head from the supraacetabular region and adjacent hip capsule. Insertion: Patella through the quadriceps tendon, with force transmitted by the patellar ligament to the tibial tuberosity.
What is the blood supply of the rectus femoris?
Mainly lateral circumflex femoral branches, with other profunda femoris/femoral contributions.