- See:
- Innerv. Musc. Lower Limb
- Innervation of the Leg and Foot:
- Anatomy:
- common peroneal nerve is derived from (L4, L5, S1, S2) as a part of the sciatic nerve;
- posterior component, supplies short head of biceps femoris in thigh, crosses posterior to lateral head of gastrocnemius,
and becomes subQ behind head of fibula;
- it penetrates the posterior intermuscular septum, and becomes closely opposed to the periosteum of the proximal fibula;
- it then divides into superficial & deep peroneal nerves;
- nerve also gives off a lateral sural cutaneous brach which joins with the the medial sural cutaneous nerve (from tibial nerve) to
form the sural nerve;
- references:
- Fibular Head as a Landmark for Identification of the Common Peroneal Nerve: A Cadaveric Study
- superficial peroneal nerve:
- supplies lateral compartment of leg, first passing between peroneus longus
- passes in a straight line from the common peroneal nerve;
- along the length of the proximal one third of the fibula, the superficial peroneal nerve is on the lateral cortex of the fibula;
- passes between peroneus longus & peroneus brevis;
- superficial sensory nerves:
- subcutaneous superficial sensory branch lies between peroneus brevis and EDL msucles.
- superficial peroneal nerve is accompanied by a true vascular axis that is supplied by tibialis anterior artery along its course.
- about 10-12 cm above the tip of the lateral malleolus, the superficial peroneal nerve pierces the fascia;
- about 6-7 cm distal to the fibula, the superficial peroneal nerve bifurcates into intermediate and medial dorsal
cutaneous nerves;
- location of cutaneous nerves: (from Huene and Bunnell (1995))
- branches of the superficial peroneal nerve or the sural nerve may be injured during ORIF of Ankle frx;
- these nerves are most at risk at the junction of the distal and middle thirds of the lateral border of the fibula;
- in 22% of legs, braches of either nerve will cross the frx site;
- in 54% of legs, branches of superficial peroneal will lie within 5 mm of the anterolateral border of the fibula;
- safest interval is 12 mm posterior to anterolateral border of fibula at 10 cm from fibular tip, and 10 mm posterior to
anterolateral border at 5 cm proximal to tip;
- deep peroneal nerve:
- courses anteriorly around fibula, taking a sharp turn as it rounds the fibular neck, to enter anterior compartment of leg;
- because of the sharp turn, the nerve is more tethered than the superficial branch;
- immediately below the fibular head, the deep peroneal nerve lies on the anterior cortex of the fibula for a distance of 3-4 cm;
- nerve passes under the intermuscular septum (between lateral and anterior compartments) which is a point of entrapment;
- note that when this septum is pulled taunt, it compresses the deep peroneal nerve w/o affecting the superficial nerve;
- it supplies anterior compartment muscles as it travels w/ the the anterior tibial artery, lying between the tibialis anterior
and the EHL;
- it passes underneath extensor retinaculum, sends a motor branch to EDB, and finally sends a sensory branch to the
interspace between the first and second toes;
- deep peroneal nerve block:
- provides anesthesia over the first webspace, with some deep contribution to joints of the lesser toes;
- from medial to lateral: EHL, Dorsalis pedis artery, Deep Peroneal Nerve, EDL;
- 2-3 cm distal to intermalleolar line, inject just above bone, between EHL and DP pulse;
- references:
- Palsy of the deep peroneal nerve after proximal tibial osteotomy. An anatomical study.
- Relationship of the common peroneal nerve and its branches to the head and neck of the fibula.
- New York School of Regional Anesthesia
- Anesthesia UK.
- Clinical importance of the lateral branch of the deep peroneal nerve.
- superficial peroneal nerve block:
- provides anesthesia over the superolateral foot;
- in thin patients the nerve can often be visualized by stretching the skin over the dorsum of the foot;
- subcutaneous "field block" with continuous wheal from lateral margin of achilles tendon around anterior ankle to the medial
margin of achilles tendon will anesthetize all superficial nerves of the foot: superficial peroneal, saphenous, and sural;
- references:
- Surgical anatomy of the superficial peroneal nerve in the ankle and foot.
- Anatomical variations in the course of the superficial peroneal nerve.
- Operative anatomy of nerves encountered in the lateral approach to the distal part of the fibula.
- Anatomic relations between ankle arthroscopic portal sites and superficial peroneal and saphenous nerves.
- New York School of Regional Anesthesia.
- Anesthesia UK.
Peroneal nerve repair. Surgical results.
Peroneal nerve palsy after early cast application for femoral fractures in children.
New tendon transfer for correction of drop-foot in common peroneal nerve palsy.
Tendon transfers for drop foot correction: long-term results including quality of life assessment, and dynamometric and pedobarographic measurements
Surgical Decompression Improves Symptoms of Late Peroneal Nerve Dysfunction After TKA