Femoral nerve is the major nerve supplying the anterior compartment of the thigh. It is the largest branch of the lumbar plexus, and arises from the dorsal divisions of the ventral rami of the second, third, and fourth lumbar nerves (L2, L3, and L4).
The nerve enters the femoral triangle by passing beneath the inguinal ligament, just lateral to the femoral artery. In the thigh, the nerve lies in a groove between iliacus muscle and psoas major muscles, outside the femoral sheath, and lateral to the femoral artery. After a short course of about 4 cm in the thigh, the nerve is divided into anterior and posterior divisions, separated by lateral femoral circumflex artery. The branches are shown below:
- The anterior division gives off Anterior cutaneous branches: The anterior cutaneous branches are: "intermediate femoral cutaneous nerve" and "medial femoral cutaneous nerve".
- The posterior division gives off only one branch, which is the saphenous nerve.
- Hip joint is supplied by nerve to the rectus femoris.
- Knee joint is supplied by the nerves to the three vasti. The nerve to vastus medialis is particularly thick because it contains the proprioceptive fibres from the knee joint. This is in accordance to the Hilton's law.
- Branches to the femoral artery and its branches.