Sural

Two or more branches which pierce the fascia over the popliteal space and supply the skin over the calf of the leg for a variable distance.

The Great Sciatic nerve passes through the sacro-sciatic foramen below pyriformis between it and the superior gemellus. Covered by gluteus maximus, it passes down, into the thigh, accompanied by the sciatic artery and a special artery of its own (arteria comes nervi ischiadici). It lies in the hollow between the great trochanter and the tuberosity of the ischium, and enters the thigh beneath the lower border of gluteus maximus. Lying between it and the origin of the hamstrings, it is comparatively superficial. In the thigh it lies on adductor magnus, and is covered by the hamstrings, and at a variable point between the sacro-sciatic foramen and the upper part of the popliteal space divides into the internal and external popliteal nerves.

Branches

Muscular to the hamstrings and short head of biceps.

Articular to the knee-joint.

The External Popliteal Nerve

One of the terminal branches of the great sciatic nerve passes beneath the tendon of biceps obliquely through the upper and outer part of the popliteal space; it then passes over the outer head of gastrocnemius, and just below the head of the fibula divides into its terminal branches, the anterior tibial and musculo-cutaneous nerves.

Branches

Cutaneous to the skin over the calf of the leg. Peroneal communicating joins a similar branch from the tibial nerve to form the short saphenous nerve.

Muscular

Recurrent tibial, which, passing forwards, supplies Tibialis anticus (upper fibres).

Articular

Branches to the knee-joint and tibio-fibular articulation from the recurrent tibial.

The Anterior Tibial nerve passes beneath peroneus longus and the extensors of the toes to the front of the leg. With the anterior tibial artery it lies on the interosseous membrane and the lower part of the tibia. Passing beneath the anterior annular ligament, it divides on the dorsum of the foot into its terminal branches.

Branches

Muscular to tibialis anticus, extensor proprius hallucis, extensor longus digitorum and peroneus tertius, and extensor brevis digitorum (from its external terminal branch).

Articular to ankle-joint and tarsal and metatarsal joints (from its external terminal branch).

Cutaneous from the internal terminal branches. The nerve passes along the dorsum of the foot on the outer side of the dorsalis pedis artery and supplies the skin of the cleft, between the first and second toes.

The Musculo-Cutaneous nerve passes down the leg, lying between the peronei and the extensor muscles. In the lower third of the leg it pierces the deep fascia and divides into its two terminal branches-internal and external.

Branches

Muscular to peroneus longus and brevis.

Cutaneous to the lower third of the skin of the leg, and, passing over the anterior annular ligament, to the dorsum of the foot, the inner side of the great toe and the skin of the clefts between the toes, not excepting the one also supplied by the anterior tibial nerve.