Common fibular (peroneal) nerve

Origin and course

The common fibular (peroneal) nerve (root value L4-S2) is the smaller of two terminal branches of the sciatic nerve, the other being the tibial nerve. The common fibular (peroneal) nerve contains mainly fibers derived from the posterior division of the sacral plexus.

The nerve arises from the sciatic nerve at the distal third of the thigh, near the apex of the popliteal fossa. It then traverses the popliteal fossa inferolaterally, towards the fibular head. In the fossa, it is positioned medially to the tendon of the biceps femoris muscle, and lateral to the gastrocnemius muscle. The nerve then pierces the fascia of the leg to enter the anterior compartment of the leg. The common fibular nerve wraps around the fibular neck. Then, the nerve terminates by dividing into two terminal branches, the superficial and deep fibular (peroneal) nerves, underneath the fibularis longus muscle.

Learning the nervous system can be very challenging. Try out nervous system quizzes and diagrams and soon you will see there’s nothing to be afraid of!

Superficial fibular (peroneal) nerve

The superficial branch of the common peroneal nerve, also known as the superficial fibular (peroneal) nerve, arises at the bifurcation of the common peroneal nerve, between the fibula and the proximal part of fibularis longus muscle.

This nerve then descends deep to the fibularis longus muscle. It pierces the deep fascia in the distal third of the leg and subsequently divides into the medial dorsal cutaneous nerve and the intermediate dorsal cutaneous nerve. The superficial fibular (peroneal) nerve provides the motor supply to the fibularis longus and fibularis brevis muscles, and sensory supply to the skin of the lower anterolateral aspect of the leg.

Deep fibular (peroneal) nerve

The deep branch of the fibular nerve, also known as the deep fibular (peroneal) nerve, arises from the bifurcation of the common fibular nerve as well. This nerve runs through the interosseous membrane to enter the extensor (anterior) compartment of the leg for which it provides innervation.

The nerve then descends between the tibialis anterior and extensor hallucis longus on the crural interosseous membrane, accompanied by the anterior tibial artery. The deep fibular nerve terminates by dividing into lateral and medial terminal branches.

Innervation

The common fibular nerve is a mixed nerve that carries motor and sensory fibers for the innervation of the muscles and skin of the leg and foot. Additionally, it provides the articular branches that innervate the ankle joint, tarsal and metatarsophalangeal joints.