Nerves of the Leg and Foot (Posterior View)

[Continued from above] . . . body.

Some of the impulses are sent from various parts of the brain and spinal cord; some come from sense organs located in the joints, ligaments, and tendons; and some come from the muscles themselves.

The nerves of the leg and foot include the lumbar plexus, sacral plexus, femoral nerve, sciatic nerve, common fibular nerve, superficial fibular nerve, saphenous nerve, sural nerve, the deep and superficial peroneal nerves, and the tibial nerve.

The lumbar plexus nerves run over the hip joint and the front portion of the thigh. The sacral plexus includes sensory and motor nerves for an area of the pelvis, the back of the thigh, a large portion of the lower leg and the foot. The femoral nerve is a branch that stems from the lumbar nerve and divides into many smaller branches to supply motor impulses to the muscles of the thighs and legs; the femoral nerves receive sensory impulses from the skin of the thighs and the lower legs.

The sciatic nerve is the largest and longest nerve in the body. It descends into the buttocks and into the thighs to supply nerve impulses to and from the muscles and skin in the hip joints and thighs, the lower legs, feet and most of the skin below the knee. The saphenous nerve is the largest and longest branch of the femoral nerve; it supplies the skin on the inside of the leg as well as the inside of the foot and small toe. The common fibular nerve flows across the leg to the fibula’s head. The superficial fibular nerve supplies the muscles and skin along the foot’s dorsum with nerves. The tibial nerve is one of two divisions of the sciatic nerves. The many branches of these nerves supply nerve impulses to and from the muscles and skin in the hip joints and thighs, the lower legs, feet and most of the skin below the knee.

The nerves of the foot help move the body and keep balance both while it's moving and at rest. Many of these nerves come from the leg, down through the ankle and into the foot. The sural nerve runs behind the outside area of the ankle and is responsible for feeling on the outside of the foot and the small toe.

Other nerves of the foot include the medial calcaneal nerve, medial and lateral plantar nerves, and the dorsal digital nerves. The medial and lateral plantar nerves are the two largest nerves in the bottom of the foot. The medial is the larger of the two. The dorsal digital nerves are on the top of the foot. They are actually bundles of nerves that command the many small bones of the toes to create the constant, subtle shifting of the feet that keeps us from falling down.

The nerves deliver messages to the brain that bring information about the angles and position of joints, the length and tension of muscles, or even the speed of movements so that through the interaction of the nervous system with the muscles of the lower extremities, balance may be maintained.

The average nerve running from the base of the spine to the tip of a toe is about three feet long. This includes a major neural transmission network within the legs that produces contractions of groups of muscles and is responsible for larger muscular functions, such as running, walking or swimming. Finer nerve bundles command the many small bones of the toes to create the constant, subtle shifting of the feet that keeps us from falling down.