{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,17]],"date-time":"2026-07-17T16:55:37Z","timestamp":1784307337387,"version":"3.55.0"},"reference-count":44,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2023,12,19]],"date-time":"2023-12-19T00:00:00Z","timestamp":1702944000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JCM"],"abstract":"<jats:p>This study investigated the prevalence of embryonic and connective tissue elements in the filum terminale (FT) of patients with tethered cord syndrome (TCS), examining both typical and pathological histology. The FT specimens from 288 patients who underwent spinal cord detethering from 2013 to 2021 were analyzed. The histopathological examination involved routine hematoxylin and eosin staining and specific immunohistochemistry when needed. The patient details were extracted from electronic medical records. The study found that 97.6% of the FT specimens had peripheral nerves, and 70.8% had regular ependymal cell linings. Other findings included ependymal cysts and canals, ganglion cells, neuropil, and prominent vascular features. Notably, 41% showed fatty infiltration, and 7.6% had dystrophic calcification. Inflammatory infiltrates, an underreported finding, were observed in 3.8% of the specimens. The research highlights peripheral nerves and ganglion cells as natural components of the FT, with ependymal cell overgrowth and other tissues potentially linked to TCS. Enlarged vessels may suggest venous congestion due to altered FT mechanics. The presence of lymphocytic infiltrations and calcifications provides new insights into structural changes and mechanical stress in the FT, contributing to our understanding of TCS pathology.<\/jats:p>","DOI":"10.3390\/jcm13010006","type":"journal-article","created":{"date-parts":[[2023,12,19]],"date-time":"2023-12-19T06:03:11Z","timestamp":1702965791000},"page":"6","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["The Surgical Histopathology of the Filum Terminale: Findings from a Large Series of Patients with Tethered Cord Syndrome"],"prefix":"10.3390","volume":"13","author":[{"given":"Hael","family":"Abdulrazeq","sequence":"first","affiliation":[{"name":"Department of Neurosurgery, Warren Alpert Medical School of Brown University, Providence, RI 02903, USA"},{"name":"Department of Neurosurgery, Rhode Island Hospital, Providence, RI 02903, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6282-828X","authenticated-orcid":false,"given":"Owen P.","family":"Leary","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Warren Alpert Medical School of Brown University, Providence, RI 02903, USA"},{"name":"Department of Neurosurgery, Rhode Island Hospital, Providence, RI 02903, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Oliver Y.","family":"Tang","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, University of Pittsburgh Medical Center, Pittsburgh, PA 15213, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2780-7114","authenticated-orcid":false,"given":"Helen","family":"Karimi","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Tufts Medical School, Boston, MA 02111, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Abigail","family":"McElroy","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, University of Pittsburgh Medical Center, Pittsburgh, PA 15213, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ziya","family":"Gokaslan","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Warren Alpert Medical School of Brown University, Providence, RI 02903, USA"},{"name":"Department of Neurosurgery, Rhode Island Hospital, Providence, RI 02903, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael","family":"Punsoni","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Warren Alpert Medical School of Brown University, Providence, RI 02903, USA"},{"name":"Laboratory Medicine, Department of Pathology, Rhode Island Hospital, Providence, RI 02903, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"John E.","family":"Donahue","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Warren Alpert Medical School of Brown University, Providence, RI 02903, USA"},{"name":"Department of Neurosurgery, Rhode Island Hospital, Providence, RI 02903, USA"},{"name":"Laboratory Medicine, Department of Pathology, Rhode Island Hospital, Providence, RI 02903, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9894-7723","authenticated-orcid":false,"given":"Petra M.","family":"Klinge","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Warren Alpert Medical School of Brown University, Providence, RI 02903, USA"},{"name":"Department of Neurosurgery, Rhode Island Hospital, Providence, RI 02903, 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Morphol."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"e492","DOI":"10.1016\/j.wneu.2022.03.038","article-title":"Diseased Filum Terminale as a Cause of Tethered Cord Syndrome in Ehlers-Danlos Syndrome: Histopathology, Biomechanics, Clinical Presentation, and Outcome of Filum Excision","volume":"162","author":"Klinge","year":"2022","journal-title":"World Neurosurg."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"e221","DOI":"10.1016\/j.wneu.2020.01.131","article-title":"Surgical Treatment of Tethered Cord Syndrome in Adults: A Systematic Review and Meta-Analysis","volume":"137","author":"Smitherman","year":"2020","journal-title":"World Neurosurg."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"101773","DOI":"10.1016\/j.inat.2023.101773","article-title":"Adult-Onset Tethered Cord Syndrome: Case Series from a Comprehensive Interdisciplinary Spine Center","volume":"33","author":"Leary","year":"2023","journal-title":"Interdiscip. Neurosurg."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"2141","DOI":"10.1007\/s00381-011-1414-0","article-title":"SEM Study on Filum Terminale with Tethered Cord Syndrome","volume":"27","author":"Liu","year":"2011","journal-title":"Childs Nerv. Syst. ChNS Off. J. Int. Soc. Pediatr. Neurosurg."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"618","DOI":"10.1227\/neu.0000000000002081","article-title":"Not Just an Anchor: The Human Filum Terminale Contains Stretch Sensitive and Nociceptive Nerve Endings and Responds to Electrical Stimulation with Paraspinal Muscle Activation","volume":"91","author":"Klinge","year":"2022","journal-title":"Neurosurgery"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"57","DOI":"10.1067\/j.cpradiol.2012.06.002","article-title":"Congenital Spinal Cord Anomalies: A Pictorial Review","volume":"42","author":"Gupta","year":"2013","journal-title":"Curr. Probl. Diagn. Radiol."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"3","DOI":"10.1007\/s00381-002-0665-1","article-title":"Is a Filum Terminale with a Normal Appearance Really Normal?","volume":"19","author":"Vatansever","year":"2003","journal-title":"Childs Nerv. Syst. ChNS Off. J. Int. Soc. Pediatr. Neurosurg."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"308","DOI":"10.1001\/archneurpsyc.1933.02240080098008","article-title":"The Normal Histology of the Intradural Filum Terminale","volume":"29","author":"Harmeier","year":"1933","journal-title":"Arch. Neurol. Psychiatry"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"1500","DOI":"10.1227\/NEU.0b013e31820ee282","article-title":"Retained Medullary Cord in Humans: Late Arrest of Secondary Neurulation","volume":"68","author":"Pang","year":"2011","journal-title":"Neurosurgery"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"531","DOI":"10.1016\/j.nec.2007.04.001","article-title":"Tethered Cord Syndrome","volume":"18","author":"Agarwalla","year":"2007","journal-title":"Neurosurg. Clin. N. Am."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"1136","DOI":"10.1111\/his.13469","article-title":"The Pathology of Lumbosacral Lipomas: Macroscopic and Microscopic Disparity Have Implications for Embryogenesis and Mode of Clinical Deterioration","volume":"72","author":"Jones","year":"2018","journal-title":"Histopathology"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"559","DOI":"10.3171\/2014.2.PEDS13528","article-title":"Filum Terminale Lipomas: Imaging Prevalence, Natural History, and Conus Position","volume":"13","author":"Cools","year":"2014","journal-title":"J. Neurosurg. Pediatr."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"362","DOI":"10.3171\/2014.1.PEDS13520","article-title":"Histological Structure of Filum Terminale in Human Fetuses","volume":"13","author":"Kural","year":"2014","journal-title":"J. Neurosurg. Pediatr."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"978","DOI":"10.1227\/01.NEU.0000210224.54816.40","article-title":"Ultrastructural Study of the Filum Terminale and Its Elastic Fibers","volume":"58","author":"Fontes","year":"2006","journal-title":"Neurosurgery"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"722","DOI":"10.1179\/016164104225018027","article-title":"Pathophysiology of Tethered Cord Syndrome and Other Complex Factors","volume":"26","author":"Yamada","year":"2004","journal-title":"Neurol. Res."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"255","DOI":"10.3171\/2013.12.PEDS13370","article-title":"Clinical Significance of Imaging and Histological Characteristics of Filum Terminale in Tethered Cord Syndrome","volume":"13","author":"Thompson","year":"2014","journal-title":"J. Neurosurg. Pediatr."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"9978","DOI":"10.1038\/s41598-019-46444-w","article-title":"Evaluation of the Structure of Myodural Bridges in an Equine Model of Ehlers-Danlos Syndromes","volume":"9","author":"McElroy","year":"2019","journal-title":"Sci. Rep."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"3505","DOI":"10.1007\/s00701-023-05568-9","article-title":"Microsurgical Approach for Resection of the Filum Terminale Internum in Tethered Cord Syndrome-a Case Demonstration of Technical Nuances and Vignettes","volume":"165","author":"Abdulrazeq","year":"2023","journal-title":"Acta Neurochir."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"759","DOI":"10.1007\/s00381-015-2627-4","article-title":"Pathological Evaluation of the Filum Terminale Tissue after Surgical Excision","volume":"31","author":"Emmez","year":"2015","journal-title":"Childs Nerv. Syst. ChNS Off. J. Int. Soc. Pediatr. Neurosurg."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"323","DOI":"10.3174\/ajnr.A7791","article-title":"Diagnostic Utility of 3D Gradient-Echo MR Imaging Sequences through the Filum Compared with Spin-Echo T1 in Children with Concern for Tethered Cord","volume":"44","author":"Rafiee","year":"2023","journal-title":"Am. J. Neuroradiol."},{"key":"ref_24","first-page":"214","article-title":"Minimal Tethered Cord Syndrome Associated with Thickening of the Terminal Filum","volume":"105","author":"Selden","year":"2006","journal-title":"J. Neurosurg."},{"key":"ref_25","first-page":"6","article-title":"The Filum Terminale Internum and Externum: A Comprehensive Review","volume":"40","author":"Saker","year":"2017","journal-title":"J. Clin. Neurosci. Off. J. Neurosurg. Soc. Australas."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"e464","DOI":"10.1016\/j.wneu.2019.05.184","article-title":"Anatomical and Histological Analysis of a Complex Structure Too Long Considered a Simple Ligament: The Filum Terminale","volume":"129","author":"Picart","year":"2019","journal-title":"World Neurosurg."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"1721","DOI":"10.1148\/radiographics.20.6.g00nv151721","article-title":"Neoplasms of the Spinal Cord and Filum Terminale: Radiologic-Pathologic Correlation","volume":"20","author":"Koeller","year":"2000","journal-title":"Radiographics"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"201","DOI":"10.1007\/BF02115238","article-title":"The Normal Vascularization of the Intradural Filum Terminale in Man","volume":"10","author":"Djindjian","year":"1988","journal-title":"Surg. Radiol. Anat."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"318","DOI":"10.1016\/S0090-3019(97)00377-7","article-title":"Management of Tight Filum Terminale Syndrome with Special Emphasis on Normal Level Conus Medullaris (NLCM)","volume":"50","year":"1998","journal-title":"Surg. Neurol."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"E9","DOI":"10.3171\/2010.3.FOCUS1085","article-title":"Spinal Cord Traction, Vascular Compromise, Hypoxia, and Metabolic Derangements in the Pathophysiology of Tethered Cord Syndrome","volume":"29","author":"Filippidis","year":"2010","journal-title":"Neurosurg. Focus"},{"key":"ref_31","first-page":"302","article-title":"Occult Tethered Cord Syndrome: The Case for Surgery","volume":"104","author":"Selden","year":"2006","journal-title":"J. Neurosurg."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"e795","DOI":"10.1016\/j.wneu.2018.10.149","article-title":"Angioarchitecture of Filum Terminale Arteriovenous Fistulas: Relationship with a Tethered Spinal Cord","volume":"122","author":"Takai","year":"2019","journal-title":"World Neurosurg."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"191","DOI":"10.1136\/neurintsurg-2017-013309","article-title":"Arteriovenous Fistulae of the Filum Terminale","volume":"10","author":"Giordan","year":"2018","journal-title":"J. Neurointerventional Surg."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"276","DOI":"10.1016\/j.jns.2016.08.054","article-title":"Lumbar Disc Herniation Exacerbating Venous Hypertension from a Spinal Perimedullary Arteriovenous Fistula of the Filum Terminale","volume":"369","author":"Ding","year":"2016","journal-title":"J. Neurol. Sci."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"E780","DOI":"10.1227\/NEU.0b013e31821bc64c","article-title":"Sacral Intradural Arteriovenous Fistula Treated Indirectly by Transection of the Filum Terminale: Technical Case Report","volume":"69","author":"Witiw","year":"2011","journal-title":"Neurosurgery"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"15","DOI":"10.1007\/s10143-016-0713-z","article-title":"Spinal Vascular Malformations: Treatment Strategies and Outcome","volume":"40","author":"Flores","year":"2017","journal-title":"Neurosurg. Rev."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"1712","DOI":"10.3171\/2015.3.JNS142446","article-title":"Arteriovenous Malformation of the Filum Terminale: An Exceptional Case","volume":"124","author":"Troude","year":"2016","journal-title":"J. Neurosurg."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"104","DOI":"10.1215\/15228517-5-2-104","article-title":"Neurolymphomatosis","volume":"5","author":"Baehring","year":"2003","journal-title":"Neuro-Oncol."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"133","DOI":"10.1186\/s13256-021-02714-8","article-title":"Neurolymphomatosis of the Median Nerve, Optic Nerve, L4 Spinal Nerve Root and Cauda Equina in Patients with B-Cell Malignancies: A Case Series","volume":"15","author":"Alazawi","year":"2021","journal-title":"J. Med. Case Rep."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"226","DOI":"10.1002\/ajmg.c.31555","article-title":"Mast Cell Disorders in Ehlers-Danlos Syndrome","volume":"175","author":"Seneviratne","year":"2017","journal-title":"Am. J. Med. Genet. C Semin. Med. Genet."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"195","DOI":"10.1002\/ajmg.c.31549","article-title":"Neurological and Spinal Manifestations of the Ehlers-Danlos Syndromes","volume":"175","author":"Henderson","year":"2017","journal-title":"Am. J. Med. Genet. C Semin. Med. Genet."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"183","DOI":"10.5435\/00124635-199707000-00001","article-title":"Calcific Tendinopathy of the Rotator Cuff: Pathogenesis, Diagnosis, and Management","volume":"5","author":"Uhthoff","year":"1997","journal-title":"J. Am. Acad. Orthop. Surg."},{"key":"ref_43","first-page":"239","article-title":"Arachnoiditis Ossificans of the Cauda Equina. Case Report and Review of the Literature","volume":"97","author":"Faure","year":"2002","journal-title":"J. Neurosurg."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"116","DOI":"10.1016\/j.wneu.2021.01.057","article-title":"Arachnoiditis Ossificans of the Lumbar Spine: A Rare Cause of Progressive Cauda Equina Syndrome","volume":"148","author":"Benyaich","year":"2021","journal-title":"World Neurosurg."}],"container-title":["Journal of Clinical Medicine"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2077-0383\/13\/1\/6\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T21:41:13Z","timestamp":1760132473000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2077-0383\/13\/1\/6"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2023,12,19]]},"references-count":44,"journal-issue":{"issue":"1","published-online":{"date-parts":[[2024,1]]}},"alternative-id":["jcm13010006"],"URL":"https:\/\/doi.org\/10.3390\/jcm13010006","relation":{},"ISSN":["2077-0383"],"issn-type":[{"value":"2077-0383","type":"electronic"}],"subject":[],"published":{"date-parts":[[2023,12,19]]}}}