The deep fibular nerve (also known as deep peroneal nerve) begins at the bifurcation of the

common fibular nerve The common fibular nerve (also known as the common peroneal nerve, external popliteal nerve, or lateral popliteal nerve) is a nerve in the lower leg that provides sensation over the posterolateral part of the leg and the knee joint. It divides at ...

between the

fibula The fibula or calf bone is a leg bone on the lateral side of the tibia, to which it is connected above and below. It is the smaller of the two bones and, in proportion to its length, the most slender of all the long bones. Its upper extremity ...

and upper part of the fibularis longus, passes infero-medially, deep to the

extensor digitorum longus The extensor digitorum longus is a pennate muscle, situated at the lateral part of the front of the leg. Origin and insertion It arises from the lateral condyle of the tibia; from the upper three-quarters of the anterior surface of the body of ...

, to the anterior surface of the

interosseous membrane An interosseous membrane is a thick dense fibrous sheet of connective tissue that spans the space between two bones, forming a type of syndesmosis joint. Interosseous membranes in the human body: * Interosseous membrane of forearm The interosse ...

, and comes into relation with the

anterior tibial artery The anterior tibial artery is an artery of the leg. It carries blood to the anterior compartment of the leg and dorsal surface of the foot, from the popliteal artery. Structure Course The anterior tibial artery is a branch of the popliteal a ...

above the middle of the leg; it then descends with the artery to the front of the ankle-joint, where it divides into a ''

lateral Lateral is a geometric term of location which may refer to: Healthcare *Lateral (anatomy), an anatomical direction *Lateral cricoarytenoid muscle *Lateral release (surgery), a surgical procedure on the side of a kneecap Phonetics *Lateral cons ...

'' and a '' medial terminal branch''.

Structure

Lateral side of the leg

The deep fibular nerve is the nerve of the anterior compartment of the leg and the dorsum of the foot. It is one of the terminal branches of the

. It corresponds to the posterior interosseus nerve of the forearm. It begins at the lateral side of the fibula bone, and then enters the anterior compartment by piercing the anterior intermuscular septum. It then pierces the

and lies next to the

, following the course of the artery until the ankle-joint where the nerve divides into medial and lateral terminal branches. In the leg, the deep fibular nerve divides into several branches: * Muscular branches: Supplies four muscles in the leg:

tibialis anterior The tibialis anterior muscle is a muscle in humans that originates along the upper two-thirds of the lateral (outside) surface of the tibia and inserts into the medial cuneiform and first metatarsal bones of the foot. It acts to dorsiflex and inve ...

extensor hallucis longus The extensor hallucis longus muscle is a thin skeletal muscle, situated between the tibialis anterior and the extensor digitorum longus. It extends the big toe and dorsiflects the foot. It also assists with foot eversion and inversion. Stru ...

, and

fibularis tertius In human anatomy, the fibularis tertius (also known as the peroneus tertius) is a muscle in the anterior compartment of the leg. It acts to tilt the sole of the foot away from the midline of the body ( eversion) and to pull the foot upward toward ...

Foot

Close to the ankle joint, the deep fibular nerve terminates by dividing into medial and lateral terminal branches. * Medial terminal branch: This nerve accompanies the

dorsalis pedis artery In human anatomy, the dorsalis pedis artery (dorsal artery of foot) is a blood vessel of the lower limb. It arises from the anterior tibial artery, and ends at the first intermetatarsal space (as the first dorsal metatarsal artery and the deep pl ...

along the dorsum of the foot, and, at the first interosseous space, divides into two dorsal digital nerves which supply the adjacent sides of the great and second toes, communicating with the medial dorsal cutaneous branch of the superficial fibular nerve. Before it divides it gives off to the first space an interosseous branch which supplies the

metatarsophalangeal joint The metatarsophalangeal joints (MTP joints), also informally known as toe knuckles, are the joints between the metatarsal bones of the foot and the proximal bones (proximal phalanges) of the toes. They are condyloid joints, meaning that an ellipt ...

of the great toe and sends a filament to the first Interosseous dorsalis muscle. * Lateral terminal branch - This nerve passes across the tarsus, beneath the

extensor digitorum brevis The extensor digitorum brevis muscle (sometimes EDB) is a muscle on the upper surface of the foot that helps extend digits 2 through 4. Structure The muscle originates from the forepart of the upper and lateral surface of the calcaneus (in fro ...

, supplying latter. This nerve ends in a pseudoganglion deep to the extensor digitorum brevis. From the pseudoganglion, three minute branches are given off to supply the tarsal joints and the metatarsophalangeal joints of the second, third, and fourth toes.

Function

In the leg, the deep fibular nerve supplies muscular branches to the anterior compartment of extensor muscles in the leg which include the

, and extensor hallucis longus (propius), and an articular branch to the ankle-joint. After its bifurcation past the ankle joint, the lateral branch of the deep fibular nerve innervates the

and the extensor hallucis brevis, while the medial branch goes on to provide cutaneous innervation to the webbing between the first and second toes.

Clinical significance

Damage to the deep fibular nerve, as is possible with traumatic injury to the lateral knee, results in

foot drop Foot drop is a gait abnormality in which the dropping of the forefoot happens due to weakness, irritation or damage to the deep fibular nerve (deep peroneal), including the sciatic nerve, or paralysis of the muscles in the anterior portion of ...

. The deep fibular nerve is also subject to injury resulting from lower motor neuron disease, diabetes, ischemia, and infectious or inflammatory conditions. Injury to the common fibular nerve is the most common isolated mononeuropathy of the lower extremity and produces sensory problems on the lateral lower leg in addition to foot drop.

Additional images

File:Gray440 color.png, Cross-section through middle of leg. File:Gray825and830.PNG, Cutaneous nerves of the right lower extremity, anterior and posterior views. File:Gray826and831.PNG, Cutaneous nerves of the right lower extremity, anterior and posterior views. File:Gray835.png, Deep nerves of the front of the leg. File:Gray836.png, Nerves of the dorsum of the foot. File:Slide1RRRR.JPG, Deep fibular nerve

References

External links

* - "The Foot: Nerves" {{Authority control Nerves of the lower limb and lower torso