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Updated: Aug 4, 2026

Dissection of the Transversus Abdominis Muscle for Whole-mount Neuromuscular Junction Analysis
Published on: January 11, 2014
Arrangement of the anal striated musculature
M Garavoglia1, F Borghi, A C Levi
1Department of Surgery, University of Turin, Italy.
Abstract:
A study of the anatomy of the anal striated musculature is performed on 34 adult specimens to reconsider some debated morphologic aspects. The original "eight-shaped" arrangement of the fibers of the pubococcygeus is pointed out, suggesting a definite role of the muscle as a superior part of the continence muscular complex; the intermediate part seems to be formed by the puborectalis loop and the deep external anal sphincter, not always separable. Finally, the inferior portion is represented by the superficial sphincter, which shows anatomic behavior similar to that of the pubococcygeus.
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