{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,3]],"date-time":"2026-09-03T12:15:33Z","timestamp":1788437733471,"version":"build-2803163510"},"reference-count":11,"publisher":"Georg Thieme Verlag KG","issue":"03","license":[{"start":{"date-parts":[[2025,3,31]],"date-time":"2025-03-31T00:00:00Z","timestamp":1743379200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Asian J Neurosurg"],"published-print":{"date-parts":[[2025,9]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Ponticulus posticus (PP), also known as arcuate foramen, is an anatomical variation of the atlas (C1), which is an ossification of the posterior atlanto-occipital membrane and through which the V3 segment of the vertebral artery (VA) runs. Placement of a polyaxial screw in the C1 lateral mass is considered risky in those with PP because of possible risk for VA injury. We report a case with bilateral PP in which posterior fixation for unstable upper cervical spine injury was performed. The patient, a 70-year-old man, sustained a fall-induced unstable upper cervical spine injury (traumatic C2 spondylolisthesis with unilateral dislocation of the C3-4 facet joint). Following initial conservative treatment, a posterior fixation surgery was performed in the subacute phase. Preoperative images revealed the presence of bilateral PP. Therefore, an original plan to place the screws in the C1 lateral mass was discarded, and instead, placement of the laminar hook on one side and placement of the screw into the C1 posterior arch on the other side was performed. His postoperative course was uneventful, and he was transferred to a rehabilitation hospital 27 days after the injury. In cases of upper cervical spine instability with concomitant PP, it is essential to consider the fixation method based on the extent of the injury and the course of the VA on a case-by-case basis.<\/jats:p>","DOI":"10.1055\/s-0045-1806836","type":"journal-article","created":{"date-parts":[[2025,3,31]],"date-time":"2025-03-31T19:55:53Z","timestamp":1743450953000},"page":"610-614","source":"Crossref","is-referenced-by-count":2,"title":["Unstable Upper Cervical Spine Injury with Concomitant Bilateral Ponticulus Posticus: A Case Report"],"prefix":"10.1055","volume":"20","author":[{"given":"Masashi","family":"Fujisawa","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Saiseikai Utsunomiya Hospital, Utsunomiya, Tochigi, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sota","family":"Wakahara","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Saiseikai Utsunomiya Hospital, Utsunomiya, Tochigi, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5076-2455","authenticated-orcid":false,"given":"Joji","family":"Inamasu","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Saiseikai Utsunomiya Hospital, Utsunomiya, Tochigi, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"194","published-online":{"date-parts":[[2025,3,31]]},"reference":[{"issue":"08","key":"ref1","doi-asserted-by":"crossref","first-page":"1520","DOI":"10.1016\/j.clineuro.2012.12.005","article-title":"Rotational vertebral artery occlusion associated with occipitoatlantal assimilation, atlantoaxial subluxation, and basilar impression","volume":"115","author":"J Inamasu","year":"2013","journal-title":"Clin Neurol Neurosurg"},{"key":"ref2","doi-asserted-by":"crossref","first-page":"61","DOI":"10.4103\/jrms.jrms_384_21","article-title":"Prevalence and characteristics of ponticulus posticus and its association with cervicogenic headache and migraine: a lateral cephalometric study","volume":"27","author":"N Mokhtari","year":"2022","journal-title":"J Res Med Sci"},{"issue":"06","key":"ref3","doi-asserted-by":"crossref","first-page":"528","DOI":"10.3340\/jkns.2015.58.6.528","article-title":"Anatomical variant of atlas: arcuate foramen, occpitalization of atlas, and defect of posterior Arch of Atlas","volume":"58","author":"M S Kim","year":"2015","journal-title":"J Korean Neurosurg Soc"},{"issue":"08","key":"ref4","doi-asserted-by":"crossref","first-page":"1102","DOI":"10.1007\/s00586-009-0925-9","article-title":"Imaging anatomy and variation of vertebral artery and bone structure at craniocervical junction","volume":"18","author":"S Duan","year":"2009","journal-title":"Eur Spine J"},{"issue":"11","key":"ref5","first-page":"2495","article-title":"The ponticulus posticus: implications for screw insertion into the first cervical lateral mass","volume":"87","author":"J P Young","year":"2005","journal-title":"J Bone Joint Surg Am"},{"issue":"01","key":"ref6","doi-asserted-by":"crossref","first-page":"360","DOI":"10.1111\/os.12868","article-title":"Multiple fractures of cervical vertebrae combined with arcuate foramen and vertebral artery occlusion: a case report and literature review","volume":"13","author":"W H Wang","year":"2021","journal-title":"Orthop Surg"},{"issue":"09","key":"ref7","doi-asserted-by":"crossref","first-page":"439","DOI":"10.2176\/nmc.45.439","article-title":"Posterior instrumentation surgery for craniocervical junction instabilities: an update","volume":"45","author":"J Inamasu","year":"2005","journal-title":"Neurol Med Chir (Tokyo)"},{"issue":"12","key":"ref8","doi-asserted-by":"crossref","first-page":"1592","DOI":"10.1016\/j.jocn.2009.03.026","article-title":"Posterior C1 lateral mass and C2 pedicle screw internal fixation for atlantoaxial instability","volume":"16","author":"Y Xie","year":"2009","journal-title":"J Clin Neurosci"},{"issue":"04","key":"ref9","doi-asserted-by":"crossref","first-page":"375","DOI":"10.1007\/s00701-005-0669-1","article-title":"Vascular injury and complication in neurosurgical spine surgery","volume":"148","author":"J Inamasu","year":"2006","journal-title":"Acta Neurochir (Wien)"},{"issue":"11","key":"ref10","first-page":"e73478","article-title":"C1 lateral mass screw insertion caudally from the C2 nerve root to avoid craniocervical fusion in a patient with atlantoaxial subluxation associated with ponticulus posticus: a case report","volume":"16","author":"S Hattori","year":"2024","journal-title":"Cureus"},{"issue":"01","key":"ref11","doi-asserted-by":"crossref","first-page":"50","DOI":"10.1007\/s005860000195","article-title":"Posterior stabilization of the cervical spine with hooks and screws. A clinical evaluation of 26 patients with traumatic, degenerative or metastatic lesions, using a new implant system","volume":"10","author":"C Hildingsson","year":"2001","journal-title":"Eur Spine J"}],"container-title":["Asian Journal of Neurosurgery"],"original-title":[],"language":"en","link":[{"URL":"http:\/\/www.thieme-connect.de\/products\/ejournals\/pdf\/10.1055\/s-0045-1806836.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,8,21]],"date-time":"2025-08-21T22:42:27Z","timestamp":1755816147000},"score":1,"resource":{"primary":{"URL":"http:\/\/www.thieme-connect.de\/DOI\/DOI?10.1055\/s-0045-1806836"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,3,31]]},"references-count":11,"journal-issue":{"issue":"03","published-online":{"date-parts":[[2025,8,21]]},"published-print":{"date-parts":[[2025,9]]}},"URL":"https:\/\/doi.org\/10.1055\/s-0045-1806836","archive":["Portico","CLOCKSS"],"relation":{},"ISSN":["1793-5482","2248-9614"],"issn-type":[{"value":"1793-5482","type":"print"},{"value":"2248-9614","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,3,31]]}}}