What is the femoral nerve and where does it originate?

The femoral nerve is the chief nerve of the anterior compartment of the thigh and the largest branch of the lumbar plexus. It originates from the posterior divisions of the anterior rami of spinal nerves L2, L3, and L4.

How does the femoral nerve enter the thigh and what are its main divisions?

It enters the thigh by passing deep to the inguinal ligament, lateral to the femoral sheath and artery. About 2 cm below the ligament, it divides into anterior and posterior divisions.

What muscles does the femoral nerve innervate?

The femoral nerve innervates key muscles in the thigh, including the sartorius (via the anterior division) and the quadriceps femoris muscles: vastus lateralis, vastus medialis, vastus intermedius, and rectus femoris (via the posterior division). It may also innervate the pectineus directly.

What sensory areas does the femoral nerve supply?

It provides cutaneous innervation to the anterior and medial thigh via the medial and intermediate cutaneous nerves, and to the medial side of the leg and foot via the saphenous nerve, which is the longest cutaneous nerve in the body.

What happens if the femoral nerve is injured?

Injury, though rare, can cause motor deficit with paralysis of the quadriceps femoris, leading to inability to extend the knee, and sensory loss in the anterior and medial thigh, and possibly the medial leg and foot via the saphenous nerve.

What are the articular branches of the femoral nerve?

The femoral nerve provides articular branches to joints, including to the hip joint via the nerve to pectineus, and to the knee joint via the nerve to vastus medialis and the saphenous nerve.

Femoral Nerve (L2–L4) – Course, Branches & Supply