Answer
sacral plexus; common fibular nerve
Work Step by Step
The sacral plexus has about a dozen named branches. About
half of these serve the buttock and lower limb; the others innervate
pelvic structures and the perineum.
The common fibular nerve branches to fibular muscles of lateral compartment of leg, tibialis anterior, and extensor muscles of toes (extensor hallucis longus, extensors digitorum longus and brevis)