{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T04:02:51Z","timestamp":1787025771273,"version":"build-2736575974"},"reference-count":26,"publisher":"Journal of Neurosurgery Publishing Group (JNSPG)","issue":"2","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2024,8,1]]},"abstract":"<jats:sec>\n                    <jats:title>OBJECTIVE<\/jats:title>\n                    <jats:p>The authors present a finite element analysis (FEA) evaluating the mechanical impact of C1\u20132 hypermobility on the spinal cord.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>METHODS<\/jats:title>\n                    <jats:p>The Code_Aster program was used to perform an FEA to determine the mechanical impact of C1\u20132 hypermobility on the spinal cord. Normative values of Young\u2019s modulus were applied to the various components of the model, including bone, ligaments, and gray and white matter. Two models were created: 25\u00b0 and 50\u00b0 of C1-on-C2 rotation, and 2.5 and 5 mm of C1-on-C2 lateral translation. Maximum von Mises stress (VMS) throughout the cervicomedullary junction was calculated and analyzed.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>RESULTS<\/jats:title>\n                    <jats:p>The FEA model of 2.5 mm lateral translation of C1 on C2 revealed maximum VMS for gray and white matter of 0.041 and 0.097 MPa, respectively. In the 5-mm translation model, the maximum VMS for gray and white matter was 0.069 and 0.162 MPa. The FEA model of 25\u00b0 of C1-on-C2 rotation revealed maximum VMS for gray and white matter of 0.052 and 0.123 MPa. In the 50\u00b0 rotation model, the maximum VMS for gray and white matter was 0.113 and 0.264 MPa.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>CONCLUSIONS<\/jats:title>\n                    <jats:p>This FEA revealed significant spinal cord stress during pathological rotation (50\u00b0) and lateral translation (5 mm) consistent with values found during severe spinal cord compression and in patients with myelopathy. While this finite element model requires oversimplification of the atlantoaxial joint, the study provides biomechanical evidence that hypermobility within the C1\u20132 joint leads to pathological spinal cord stress.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3171\/2024.2.spine231327","type":"journal-article","created":{"date-parts":[[2024,5,3]],"date-time":"2024-05-03T21:48:38Z","timestamp":1714772918000},"page":"159-166","source":"Crossref","is-referenced-by-count":7,"title":["C1\u20132 hypermobility and its impact on the spinal cord: a finite element analysis"],"prefix":"10.3171","volume":"41","author":[{"given":"Arpan A.","family":"Patel","sequence":"first","affiliation":[{"name":"Center for Spine Health, Cleveland Clinic, Cleveland, Ohio;"},{"name":"Department of Neurosurgery, Cleveland Clinic Lerner College of Medicine, Cleveland, Ohio;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jacob K.","family":"Greenberg","sequence":"additional","affiliation":[{"name":"Department of Neurological Surgery, Washington University School of Medicine, St. Louis, Missouri;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael P.","family":"Steinmetz","sequence":"additional","affiliation":[{"name":"Center for Spine Health, Cleveland Clinic, Cleveland, Ohio;"},{"name":"Department of Neurosurgery, Cleveland Clinic Lerner College of Medicine, Cleveland, Ohio;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sarel","family":"Vorster","sequence":"additional","affiliation":[{"name":"Center for Spine Health, Cleveland Clinic, Cleveland, Ohio;"},{"name":"Department of Neurosurgery, Cleveland Clinic Lerner College of Medicine, Cleveland, Ohio;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Edin","family":"Nevzati","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Cantonal Hospital of Lucerne, Switzerland; and"},{"name":"Faculty of Medicine, University of Basel, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alexander","family":"Spiessberger","sequence":"additional","affiliation":[{"name":"Center for Spine Health, Cleveland Clinic, Cleveland, Ohio;"},{"name":"Department of Neurosurgery, Cleveland Clinic Lerner College of Medicine, Cleveland, Ohio;"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1754","reference":[{"issue":"1","key":"b1","series-title":"Am J Med Genet C Semin Med Genet","first-page":"195","article-title":"Neurological and spinal manifestations of the Ehlers-Danlos syndromes","volume":"175","author":"Henderson FC Sr","year":"2017","unstructured":"Henderson FC Sr, Austin C, Benzel E,  Neurological and spinal manifestations of the Ehlers-Danlos syndromes. 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