Which nerve is primarily responsible for innervation of the posterior compartment muscles of the leg and the plantar surface of the foot?

Which nerve is primarily responsible for innervation of the posterior compartment muscles of the leg and the plantar surface of the foot?

• A. Sciatic nerve
• B. Common fibular nerve
• C. Tibial nerve
• D. Femoral nerve

Answer: (C)

Tibial nerve supplies both the posterior leg muscles and the plantar surface of the foot. It travels in the deep posterior compartment with the posterior tibial vessels, innervating the gastrocnemius, soleus, plantaris, and the deep flexors (tibialis posterior, flexor digitorum longus, flexor hallucis longus). As it enters the foot, it divides into the medial and lateral plantar nerves, which motorize most intrinsic plantar muscles and provide sensation to the sole. The common fibular nerve mostly targets the anterior and lateral compartments of the leg and the dorsum of the foot, not the plantar surface. The femoral nerve serves the anterior thigh, so it’s not involved here.

Tibial nerve supplies both the posterior leg muscles and the plantar surface of the foot. It travels in the deep posterior compartment with the posterior tibial vessels, innervating the gastrocnemius, soleus, plantaris, and the deep flexors (tibialis posterior, flexor digitorum longus, flexor hallucis longus). As it enters the foot, it divides into the medial and lateral plantar nerves, which motorize most intrinsic plantar muscles and provide sensation to the sole. The common fibular nerve mostly targets the anterior and lateral compartments of the leg and the dorsum of the foot, not the plantar surface. The femoral nerve serves the anterior thigh, so it’s not involved here.