The superficial peroneal nerve provides motor innervation to which muscles?

• A. Tibialis posterior and gastrocnemius
• B. Peroneus longus and peroneus brevis
• C. Soleus and plantaris
• D. Rectus femoris and vastus lateralis

Answer: (B)

The key idea is how leg muscles are grouped and innervated by specific nerves. The superficial peroneal (fibular) nerve supplies the muscles of the lateral compartment of the leg—the peroneus longus and peroneus brevis. These two muscles are responsible for everting the foot (with some assist from plantarflexion), so they are the ones this nerve motor-innervates.

The other muscles listed are innervated by different nerves: tibialis posterior and gastrocnemius are innervated by the tibial nerve; soleus and plantaris are also tibial; and rectus femoris and vastus lateralis are controlled by the femoral nerve.