Liver — Lobes, Couinaud Segments & Relations — Practice
A 25-year-old woman has a difficult forceps delivery and afterwards cannot voluntarily contract the external anal sphincter or feel the perianal skin. The pudendal nerve was injured. Which spinal segments constitute the origin of this nerve?
AS2, S3, S4
BL5, S1, S2
CL4, L5, S1
DS1, S2, S3