Vastus intermedius
Thighs
Deep muscle — it lies under other muscles. X-ray makes the muscles over it see-through.
- Origin
- Front and lateral surfaces of the femoral shaft
- Insertion
- Tibial tuberosity via the patellar tendon
- Action
- Extends the knee
- Nerve supply
- Femoral nerve (L2–L4)
The deepest quadriceps muscle, lying directly on the femur under the rectus femoris. Use X-ray mode to see it.