The femoral nerve is one of the major nerves that innervates the legs. Its principal function is to carry instructions to the muscles that straighten the leg, such as the quadriceps, found in the anterior thigh.
This nerve has a triangular transverse cross section and passes through the pelvic region in the grove between the iliacus and psoas muscles. It splits off from the spinal cord between the second and fourth lumbar vertebrae and, in addition to its motor functions, carries sensory information from the skin covering the anterior thigh and shin. One other major nerve, the saphenous nerve, branches off the femoral nerve. The saphenous nerve carries instructions and sensory information to the foot.
The femoral nerve can be susceptible to damage from pelvic fractures because if the anterior pelvic bones crack, they can press on and possibly sever the femoral nerve. The best way to spot femoral nerve damage is if leg movement becomes impaired (particularly straightening the leg) and there is a lasting numbness in the area. If spotted quickly enough, femoral nerve damage is repairable via surgical correction.