Ascent of the Conus Medullaris in Human Foetuses: A Systematic Review and Meta-Analysis

Ascent of the Conus Medullaris in Human Foetuses: A Systematic Review and Meta-Analysis | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Ascent of the Conus Medullaris in Human Foetuses: A Systematic Review and Meta-Analysis Lucas Almeida, Yasmin Juliany Figueiredo, André Zylberman, Diogo Garção This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-970944/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 9 You are reading this latest preprint version Abstract The aim of the present systematic review and meta-analysis was to identify when the ascent of the conus medullaris occurs in human foetuses considering differences in evaluation methods and sample characteristics. Five databases were searched for relevant articles using different combinations of keywords. Article selection and data extraction were performed independently by two reviewers. Disagreements were resolved by a third reviewer. The variables were distributed into four groups according to the gestational age of the specimens: I (13 to 18 weeks); II (19 to 25 weeks); III (26 to 32 weeks); IV (33 weeks to the probable date of birth). Eighteen articles were included. The majority used imaging exams as the evaluation method. Cadaveric dissections were reported in the remaining articles. Only morphological studies were included in the meta-analysis. Significant ascent occurs between groups I and III as well as groups II and IV. Despite the considerable heterogeneity among the studies included in the present review, the findings enabled the determination that the conus medullaris reaches its normal birth level by the 26th week. Further analyses should be performed based on nationality and ethnicity to diminish the heterogeneity of the data. Neurology Developmental Neuroscience conus medullaris ascent foetal development spinal cord Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Major revision 22 Apr, 2022 Reviewers agreed at journal 02 Apr, 2022 Reviews received at journal 23 Feb, 2022 Reviewers agreed at journal 14 Feb, 2022 Reviewers invited by journal 03 Feb, 2022 Editor assigned by journal 03 Feb, 2022 Editor invited by journal 26 Oct, 2021 Submission checks completed at journal 26 Oct, 2021 First submitted to journal 15 Oct, 2021 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Also discoverable on Platform About Our Team In Review Editorial Policies Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-970944","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":59196288,"identity":"f3291646-bd33-46ec-a378-c64f6c8fe1d5","order_by":0,"name":"Lucas Almeida","email":"","orcid":"","institution":"Universidade Federal de Sergipe","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Lucas","middleName":"","lastName":"Almeida","suffix":""},{"id":59196289,"identity":"fba7c71d-cdf6-4747-93f4-31abb5b5eeaa","order_by":1,"name":"Yasmin Juliany Figueiredo","email":"","orcid":"","institution":"Universidade Federal de 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