Lower limb
Deep fibular nerve (Deep peroneal nerve)
Nervus fibularis profundus (peroneus profundus)
- Origin
- Medial terminal division of the common fibular nerve arising at the neck of the fibula
- Insertion
- Pierces the anterior intermuscular septum, travels with anterior tibial vessels down the anterior compartment, passes deep to the extensor retinaculum to terminate on the foot dorsum
- Function
- Motor to all anterior leg compartment muscles (tibialis anterior, EHL, EDL, fibularis tertius) and intrinsic dorsal foot extensors (EDB, EHB); sensory strictly to the first dorsal web space skin between digits 1 and 2
- Innervation
- Dominant motor nerve powering ankle dorsiflexion and digital extension
- Movement & chain
- Prevents foot dragging by elevating the foot and toes during heel strike preparation
- Palpation
- Sensory testing strictly localized to the skin of the first web space between the great toe and second toe
- Clinical
- Anterior tarsal tunnel syndrome (compression under the inferior extensor retinaculum from tight footwear or osteophytes); pure drop foot in anterior compartment syndrome
- Segmental innervation
- L4, L5 (S1) roots
- In clinical practice
- Pinprick testing of the first web space is the definitive diagnostic check for isolated L5 nerve root or deep peroneal nerve integrity
- Region in the model
- Lower limb