{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,22]],"date-time":"2026-08-22T05:25:28Z","timestamp":1787376328430,"version":"build-2736575974"},"reference-count":17,"publisher":"Springer Science and Business Media LLC","license":[{"start":{"date-parts":[[2026,8,22]],"date-time":"2026-08-22T00:00:00Z","timestamp":1787356800000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2026,8,22]],"date-time":"2026-08-22T00:00:00Z","timestamp":1787356800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"DOI":"10.13039\/501100001691","name":"Japan Society for the Promotion of Science","doi-asserted-by":"publisher","award":["25K18696"],"award-info":[{"award-number":["25K18696"]}],"id":[{"id":"10.13039\/501100001691","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Anat Sci Int"],"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>We aimed to clarify the attachment architecture between the levator ani and the rectum and vagina using integrated macroscopic and histological analyses of human pelvic floor specimens. Macroscopic dissection demonstrated whitish soft tissue at the interface between the levator ani and the lateral walls of the rectum and vagina. Histological and immune histochemical analyses of the corresponding regions revealed abundant smooth muscle components that appeared topographically continuous with the outer muscular layers of each organ within individual coronal sections. In both organs, the smooth muscle extended beyond the organ walls, spread over the superior and inferior surfaces of the levator ani, and interdigitated between skeletal muscle bundles, forming a serrated (saw tooth-like) interface. No dense connective tissue structures resembling tendons or aponeuroses were identified, indicating that levator ani\u2013visceral attachment does not conform to a classical tendon-mediated enthesis. Distinct attachment patterns were observed between the two organs. At the rectal interface, a subset of levator ani muscle fibers coursed toward smooth muscle that appeared topographically continuous with the rectal longitudinal layer and formed an insertion-like arrangement. In contrast, at the vaginal interface, no insertion-like arrangement of levator ani muscle fibers into the vaginal wall was observed. Abundant vaginal smooth muscle extended laterally and enveloped adjacent levator ani muscle bundles. These findings provide a clearer anatomical characterization of a non-tendinous skeletal\u2013smooth muscle interface between the levator ani and deformable pelvic visceral walls. This provides an anatomical basis for future studies investigating how the levator ani interacts mechanically with these deformable pelvic organs.<\/jats:p>","DOI":"10.1007\/s12565-026-00963-5","type":"journal-article","created":{"date-parts":[[2026,8,22]],"date-time":"2026-08-22T04:46:33Z","timestamp":1787373993000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["A skeletal\u2013smooth muscle interface mediates levator ani attachment to the rectum and vagina: a macroscopic and histological study"],"prefix":"10.1007","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4709-6359","authenticated-orcid":false,"given":"Satoru","family":"Muro","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Akimoto","family":"Nimura","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Keiichi","family":"Akita","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2026,8,22]]},"reference":[{"key":"963_CR1","doi-asserted-by":"publisher","first-page":"333","DOI":"10.32098\/mltj.03.2014.12","volume":"4","author":"J Apostolakos","year":"2014","unstructured":"Apostolakos J, Durant TJS, Dwyer CR et al (2014) The enthesis: a review of the tendon-to-bone insertion. 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The study protocol was approved by the Ethics Committee of the Institute of Science Tokyo, Japan (approval number: M2018-006).","order":2,"name":"Ethics","label":"Ethical approval","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"Written informed consent for body donation and its use for educational and research purposes was obtained from all donors before death. Following death, consent was also obtained from bereaved family members, and no objections were raised.","order":3,"name":"Ethics","label":"Consent to participate","group":{"name":"EthicsHeading","label":"Declarations"}}]}}