Pudendal nerve supplying motor pa to external sphincter is derived from
The striated sphincter is innervated by the pudendal nerve from the S2 - S3 nerve roots. The neurons that innervate the urethral sphincter originate in the cord, in an area termed Onuf&;s nucleus. The autonomic nervous system also controls the IUS muscle because it is made of smooth muscle fibers.
L5 - S1 roots
S1 - S2 roots
L2 - L3 roots
S2 - S3 roots
Abdomen and pelvis