Puborectalis (Left) (Musculus puborectalis)
Educational content only — not medical advice.
Anatomy
The puborectalis is the thickest, medialmost component of the levator ani muscle group. It forms a robust U-shaped muscular sling arising from the posterior pubic body on both sides and looping behind the anorectal junction. Resting tone in this sling creates the anorectal angle (~80–90°), which acts as a primary mechanical valve maintaining fecal continence.
Origin & insertion
From the posterior surface of the superior pubic ramus on both sides, looping uninterrupted around the posterior anorectal junction without a bony insertion.
Action
Pulls the anorectal junction anteriorly to preserve the anorectal angle for fecal continence; relaxes during defecation to allow straightening of the rectal canal.
Innervation
Nerve to levator ani (S4) and inferior rectal branches of the pudendal nerve (S2–S4).
Clinical notes
Failure of the puborectalis to relax during attempted defecation (anismus or paradoxical puborectalis contraction) is a major cause of obstructive outlet constipation; disruption leads to fecal incontinence.
Related structures
Educational references
FAQ
What is the role of the Puborectalis (Left)?
The puborectalis is the thickest, medialmost component of the levator ani muscle group. It forms a robust U-shaped muscular sling arising from the posterior pubic body on both sides and looping behind the anorectal junction. Resting tone in this sling creates the anorectal angle (~80–90°), which acts as a primary mechanical valve maintaining fecal continence.
Why is the Puborectalis (Left) clinically important?
Failure of the puborectalis to relax during attempted defecation (anismus or paradoxical puborectalis contraction) is a major cause of obstructive outlet constipation; disruption leads to fecal incontinence.
Source & license
BodyParts3D, © The Database Center for Life Science licensed under CC Attribution 4.0 International (https://creativecommons.org/licenses/by/4.0/). license details