Lower limb
Tibial nerve
Nervus tibialis
- Origin
- Larger medial terminal branch of the sciatic nerve arising in the popliteal fossa (L4–S3)
- Insertion
- Passes through the popliteal fossa, travels beneath the soleal arch, descends deep posterior leg with posterior tibial vessels, traverses the tarsal tunnel, and divides into medial and lateral plantar nerves
- Function
- Motor to all posterior leg compartment muscles (gastrocnemius, soleus, plantaris, popliteus, tibialis posterior, FDL, FHL) and all intrinsic plantar foot muscles; sensory to heel (medial calcaneal branches) and sole of the foot
- Innervation
- Mixed sensorimotor nerve driving ankle plantarflexion, toe flexion, and plantar sensation
- Movement & chain
- Generates forceful push-off during gait, running, and jumping
- Palpation
- Palpable in the midline of the popliteal fossa and posterior to the medial malleolus within the tarsal tunnel
- Clinical
- Tarsal tunnel syndrome (entrapment behind medial malleolus causing burning sole pain and paresthesias), loss of toe-standing ability, absent Achilles tendon reflex (S1)
- Segmental innervation
- L4, L5, S1, S2, S3 spinal levels
- In clinical practice
- Achilles deep tendon reflex testing (S1); Monofilament and Semmes-Weinstein sensory testing of plantar skin in diabetic peripheral neuropathy
- Region in the model
- Lower limb