Lower limb
Rectus Femoris
Musculus rectus femoris
- Origin
- Anterior inferior iliac spine (straight head) and upper rim of the acetabulum (reflected head) of the hip bone
- Insertion
- Via the common quadriceps tendon onto the patella and further via the patellar ligament onto the tibial tuberosity
- Function
- Extends the knee and flexes the hip; the only quadriceps head that spans two joints
- Innervation
- Femoral nerve (L2-L4)
- Movement & chain
- Works together with the other quadriceps heads in knee extension, but is the only one that also produces hip flexion - active in, for example, kicking a ball.
- Palpation
- Palpable in the middle of the front of the thigh, between vastus medialis and lateralis, especially during resisted knee extension.
- Clinical
- Susceptible to tears during explosive sprinting or kicking movements (proximal rectus femoris rupture), often near the anterior inferior iliac spine.
- Segmental innervation
- Femoral nerve, L2-L4.
- In clinical practice
- Commonly used site for intramuscular injections (anterolateral thigh) and reference point in physiotherapy strength testing of the quadriceps.
- Region in the model
- Lower limb