Deep fibular nerve

A crucial nerve responsible for motor and sensory functions in the lower leg and foot.

The deep fibular nerve, also known as the deep peroneal nerve, is a branch of the common fibular nerve. It primarily innervates the muscles in the front part of the lower leg and provides sensation to a small area between the first and second toes. This nerve is essential for movements like dorsiflexion.

Terminologia Anatomica

nervus fibularis profundus

System

Nervous system

Function

The deep fibular nerve plays a vital role in both motor and sensory functions. Motorically, it innervates the anterior compartment of the leg, which includes muscles such as the tibialis anterior, extensor hallucis longus, and extensor digitorum longus. These muscles are instrumental in dorsiflexing the foot, allowing the toes to lift upwards, which is critical for walking, running, and maintaining stability. Additionally, the deep fibular nerve aids in the eversion and inversion of the foot, giving control over movements essential for adaptation to different terrains. Sensory-wise, this nerve supplies the skin of the web space between the first and second toes, providing tactile feedback necessary for balance and proprioception.

Location

The deep fibular nerve originates from the common fibular nerve, which branches off from the sciatic nerve. As the common fibular nerve travels downwards, it curves around the head of the fibula, where it splits into superficial and deep branches. The deep fibular nerve then descends into the anterior compartment of the leg, passing beneath the extensor retinaculum near the ankle. Its journey continues into the dorsum of the foot, where it supplies both muscles and skin in this region. The close anatomical positioning to the fibula makes this nerve susceptible to injury, particularly through fractures or compression injuries.

Did You Know?

The deep fibular nerve can be affected by compartment syndrome, which can lead to muscle weakness or even foot drop.
An injury to the deep fibular nerve can impair the ability to lift the foot, resulting in tripping hazards.
It is often tested clinically for function during neurological examinations by assessing dorsiflexion strength and sensation.
The nerve's sensory supply covers a small area of the foot but plays a significant role in proprioception.