- Innervation of the Leg and Foot:
- Sural Artery:
- Medial sural cuteus nerve:
- tibial nerve just below knee joint gives rise to medial sural cutaneous nerve, which runs downward across union of heads of gastronemius;
- it is joined by peroneal communicating branch from common peroneal nerve (which may arise w/ lateral sural cutaneuos), thus forming sural nerve;
- Lateral sural cutaneous nerve:
- arises from common peroneal nerve above knee joint & joins w/ medial sural cutaneous; to form sural nerve;
- it runs down posterolateral aspect of calf, innervating lateral side of leg;
- supplies: lateral and adjacent parts of the posterior and anterior surfaces of the upper part of the leg;
- Sural Nerve Anatomy:
- sural nerve passes down posterolateral side of leg & onto dorsal aspect of lateral side of foot, giving rise to lateral calcaneal branches (medial branch
supplied by tibial nerve)
- sural nerve runs with the small saphenous vein on the posterior leg just lateral to the achilles tendon;
- its terminal branches consist of lateral dorsal cutaneous nerve and the lateral calcaneal braches;
- sural nerve, which lies superficial to deep fascia below knee, is used as guide to tibial nerve;
- follow sural nerve upwards to pierce deep fascia and lead to tibial nerve which is its parent trunk;
- except for unmyelinated autonomic fibers, sural is entirely sensory;
- it innervates lateral & posterior third of leg and lateral aspect of foot & heel, & lateral portion of the ankle;
- sural nerve grafts are frequently used as cable grafts:
- blood supply to the sural nerve graft usually comes thru the muscular perforating branches of the posterior tibial artery or cutaneous
branches of the peroneal artery;
- upto 25 cm of nerve graft may be harvested;
- Sural nerve block:
- provides anesthesia over the lateral portion of the foot
- needle is introduced just lateral to the Achilles tendon approx 1-2 cm proximal to the level of the distal tip of lateral malleolus;
- needle is directed to the posteromedial aspect of the fibula and 5 ml of anesthetic is injected after aspiration of the syringe;
- practically, a subcutaneous "field block" with continuous wheal from lateral margin of achilles tendon around the anterior ankle to the medial margin
of the achilles tendon will anesthetize all superficial nerves of the foot: superficial peroneal, saphenous, and sural;
- New York School of Regional Anesthesia.
- Anesthesia UK.
The sural nerve in the foot and ankle: An anatomic study with clinical and surgical implications.
The anatomic features of the sural nerve with an emphasis on its clinical importance.
Anatomy of the sural nerve and its relation to the Achilles tendon
Fourth Toe Flexion Sign: A New Clinical Sign for Identification of the Superficial Peroneal Nerve
Risk to Neurovascular Structures Using Posterolateral Percutaneous Ankle Screw Placement: A Cadaver Study
Original Text by Clifford R. Wheeless, III, MD.
Last updated by Data Trace Staff on Wednesday, April 11, 2012 11:36 am