Nerve
Femoral nerve
Anterior thigh nerve
High-yield
Enters the thigh lateral to the femoral artery (NAVEL); injury → weak knee extension and lost patellar reflex.
Overview
The largest branch of the lumbar plexus, supplying the hip flexors and knee extensors and the skin of the anterior thigh, continuing as the saphenous nerve.
Reference facts
- Roots
- L2, L3, L4 (posterior divisions of the lumbar plexus)
- Course
- Emerges lateral to psoas major, passes deep to the inguinal ligament lateral to the femoral artery, and divides in the femoral triangle
- Motor
- Iliacus, pectineus, sartorius, and quadriceps femoris
- Sensory
- Anterior thigh (anterior femoral cutaneous) and medial leg/foot (saphenous nerve)
Clinical correlation
Femoral nerve injury abolishes the knee-jerk reflex and weakens knee extension.
Frequently asked questions
What are the roots of the femoral nerve?
The femoral nerve arises from L2, L3, L4 (posterior divisions of the lumbar plexus).
What muscles does the femoral nerve supply?
The femoral nerve supplies the iliacus, pectineus, sartorius, and quadriceps femoris.
What is the sensory distribution of the femoral nerve?
The femoral nerve carries sensation from the anterior thigh (anterior femoral cutaneous) and medial leg/foot (saphenous nerve).
What is the course of the femoral nerve?
Emerges lateral to psoas major, passes deep to the inguinal ligament lateral to the femoral artery, and divides in the femoral triangle.