Pudendal nerve supplying motor pa to external anal sphincter is derived from:
Pudendal nerve supplying motor pa to external anal sphincter is derived from S2-4 roots. It provides motor innervation to perineal muscles, sphincter urethrae and levator ani. It is sensory to genitalia.Tibial nerve (L5, S1-3)- It is motor to most of the posterior thigh, posterior leg and plantar surface of the foot.Lateral femoral cutaneous nerve (L2,3) - It is sensory to the lateral thigh.Femoral nerve (L2-4)- It is motor to iliacus, psoas major, psoas minor, and muscles of the anterior thigh.Common peroneal nerve (L4-5, S1-2) - It is motor to the sho head of biceps femoris, muscles of the lateral leg, anterior leg and dorsum of foot superficial and deep peroneal branches.Superior gluteal nerve (L4,5 S1)- It is motor to the gluteus medius and minimus, and the tensor fascia lata.Inferior gluteal nerve (L5, S1-2)- It is motor to gluteus maximus.Ref: Coloring Guide to Human Anatomy By T. Alan Twietmeyer, page 104.
L5-S1 roots
S1-S2 roots
L2-L3 roots
S2-S3 roots