The internal innervation and morphology of the human female levator ani muscle

  • S. Abbas Shobeiri
    Reprints: S. Abbas Shobeiri, MD, University of Oklahoma Health Sciences Center, Department of Obstetrics and Gynecology, Section of Female Pelvic Medicine and Reconstructive Surgery, 920 Stanton L. Young Blvd., PO Box 26901, WP2410, Oklahoma City, OK 73190
    Department of Obstetrics and Gynecology, University of Oklahoma Health Sciences Center, Oklahoma City, OK
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  • Ralph R. Chesson
    Section of Female Pelvic Medicine and Reconstructive Surgery, Department of Obstetrics and Gynecology, Louisiana State University Health Sciences Center, New Orleans, LA
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  • Raymond F. Gasser
    Section of Female Pelvic Medicine and Reconstructive Surgery, Department of Obstetrics and Gynecology, Louisiana State University Health Sciences Center, New Orleans, LA
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Published:October 10, 2008DOI:


      The purpose of this study was to describe the microinnervation of the human the female levator ani muscle complex.

      Study Design

      Detailed microdissection of 10 fresh female levator ani muscles was performed. Specimens were processed by modified Sihler's staining technique. A composite drawing of the levator ani nerve (LAN) distribution was created.


      Six hemi-levator ani muscles were stained and digitally reconstructed. The LAN traveled perpendicular to major muscular bundles while progressively branching into finer nerves that eventually entered single muscle fascicles. The LAN continued its course through the iliococcygeous muscle to innervate the puborectalis, puboperinealis, and puboanalis muscles. There was no distinct separation between pubovisceralis and iliococcygeous fibers. There were muscle fibers that could be best described as coccygeoperinealis.


      The utilized staining technique enabled us to visualize the LAN microinnervation of the levator ani muscle that extends to puboperinealis and puboanalis muscles. A blueprint for LAN and levator ani morphology was created.

      Key words

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