Medial branch of deep fibular nerve

The medial branch of the deep fibular nerve is the terminal sensory branch of the deep fibular (peroneal) nerve in the foot. After the deep fibular nerve passes beneath the extensor retinaculum at the ankle, it typically bifurcates into a medial and a lateral branch approximately 12.4 mm distal to the ankle mortise. The medial branch courses over the talonavicular joint capsule, running an average of 2.9 mm lateral to the first tarsometatarsal joint, and then passes deep to the extensor hallucis brevis tendon in the forefoot. It bifurcates in the midmetatarsal region and arborizes to supply cutaneous sensation to the first dorsal web space, specifically the adjacent sides of the first and second toes.

This branch is purely sensory and is clinically significant for its role in sensation to the first web space.