Nerves - Superficial fibular

Question 1

Nerve roots of the superficial fibular

Answer 1

L4 - S1

Question 2

Motor function?

Answer 2

Muscles of the lateral compartment of the leg

Question 3

Sensory function?

Answer 3

Supplies the vast majority of the dorsum of the foot, apart from the webbing between the hallux and second digit.

Also supplies the anterior and lateral aspect of the inferior 1/3 of the leg.

Question 4

Anatomical course?

Answer 4

Superficial fibular nerve is a terminal branch of the common fibular nerve.

It arises at the neck of the fibula, descending between the fibularis muscles and the lateral side of the extensor digitorum longus. Here it gives rise to motor branches to fibularis longus and brevis. It continues to descend to provide purely cutaneous innervation to the anterolateral aspect of the leg.

When the superficial fibular nerve reaches the lower third of the leg, it pierces the crural fascia and terminated into the medial and intermedial cutaneous nerves. Those nerves enter the foot and supply the majority of the dorsum foot.

Question 5

Clinical relevance - superficial fibular nerve entrapment

Answer 5

Relatively common.

Superficial peroneal nerve entrapment (also known as nerve compression) can cause pain and paraesthesia over the lower leg and dorsum of the foot.

Entrapment occurs in ankle sprains or twisting of the ankle.

The nerve can also become entrapped by the deep fascia of the leg. This requires surgical decompression to treat.

Question 6

Clinical relevance: direct damage to the superficial fibular nerve

Answer 6

Occurs by fracture of the fibula, or by a perforating wound to the lateral leg.

Superficial fibular nerve innervates evertors. Therefore damage to this nerve may result in loss of eversion. A loss of sensation on the dorsum of the foot and anterolateral aspect of the leg may result.