{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,23]],"date-time":"2026-05-23T09:10:16Z","timestamp":1779527416148,"version":"3.53.1"},"reference-count":34,"publisher":"Journal of Neurosurgery Publishing Group (JNSPG)","issue":"4","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["FOC"],"published-print":{"date-parts":[[2015,4]]},"abstract":"<jats:sec>\n                    <jats:title>OBJECT<\/jats:title>\n                    <jats:p>Patients with occipitocervical (OC) instability from congenital vertebral anomalies (CVAs) of the craniocervical junction (CCJ) often have bony abnormalities that make instrumentation placement difficult. Within this patient population, some bilateral instrumentation constructs either fail or are not feasible, and a unilateral construct must be used. The authors describe the surgical management and outcomes of this disorder in patients in whom unilateral fixation constructs were used to treat OC instability.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>METHODS<\/jats:title>\n                    <jats:p>From a database of OC fusion procedures, the authors identified patients who underwent unilateral fixation for the management of OC instability. Patient characteristics, surgical details, and radiographic outcomes were reviewed. In each patient, CT scans were performed at least 4 months after surgery to evaluate for fusion.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>RESULTS<\/jats:title>\n                    <jats:p>Eight patients with CVAs of the CCJ underwent unilateral fixation for the treatment of OC instability. For 4 patients, the procedure occurred after a bilateral OC construct failed or infection forced hardware removal. For the remainder, it was the primary procedure. Two patients required reoperation for hardware revision and 1 developed nonunion requiring revision of the bone graft. Ultimately, 7 patients demonstrated osseous fusion on CT scans and 1 had a stable fibrous union.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>CONCLUSIONS<\/jats:title>\n                    <jats:p>These findings demonstrate that a unilateral OC fixation is effective for the treatment of OC instability in children with CVAs of the CCJ in whom bilateral screw placement fails or is not feasible.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3171\/2015.1.focus14787","type":"journal-article","created":{"date-parts":[[2015,4,1]],"date-time":"2015-04-01T13:05:25Z","timestamp":1427893525000},"page":"E9","source":"Crossref","is-referenced-by-count":12,"title":["Unilateral fixation for treatment of occipitocervical instability in children with congenital vertebral anomalies of the craniocervical junction"],"prefix":"10.3171","volume":"38","author":[{"given":"Marcus D.","family":"Mazur","sequence":"first","affiliation":[{"name":"Department of Neurosurgery, Clinical Neurosciences Center, University of Utah, Salt Lake City, Utah"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vijay M.","family":"Ravindra","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Clinical Neurosciences Center, University of Utah, Salt Lake City, Utah"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Douglas L.","family":"Brockmeyer","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Clinical Neurosciences Center, University of Utah, Salt Lake City, Utah"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1754","reference":[{"key":"b1-focus14787","series-title":"J Neurosurg","first-page":"1","article-title":"The transcondylar approach to extradural nonneoplastic lesions of the craniovertebral junction","volume":"84","author":"al-Mefty","year":"1996"},{"issue":"1 Suppl","key":"b2-focus14787","series-title":"J Neurosurg","first-page":"55","article-title":"Long-term maintenance of cervical alignment after occipitocervical and atlantoaxial screw fixation in young children","volume":"105","author":"Anderson","year":"2006"},{"key":"b3-focus14787","series-title":"Principles and Practice of Pediatric Neurosurgery","first-page":"364","article-title":"Congenital vertebral anomalies","author":"Brockmeyer","year":"2014"},{"key":"b4-focus14787","series-title":"J Neurosurg Pediatr","first-page":"357","article-title":"Atlantal hemirings and craniocervical instability: identification, clinical characteristics, and management","volume":"8","author":"Brockmeyer","year":"2011"},{"key":"b5-focus14787","series-title":"Clin Orthop Relat Res","first-page":"170","article-title":"Onlay technique for occipitocervical fusion","volume":"280","author":"Elia","year":"1992"},{"key":"b6-focus14787","series-title":"J Neurosurg Spine","first-page":"164","article-title":"Atlantoaxial transarticular screw fixation: a review of surgical indications, fusion rate, complications, and lessons learned in 67 pediatric patients","volume":"2","author":"Gluf","year":"2005"},{"key":"b7-focus14787","series-title":"J Neurosurg Spine","first-page":"397","article-title":"Outcomes of instrumented fusion in the pediatric cervical spine","volume":"17","author":"Hwang","year":"2012"},{"key":"b8-focus14787","series-title":"Neurosurg Clin N Am","first-page":"463","article-title":"Congenital anomalies of the cervical spine","volume":"18","author":"Klimo","year":"2007"},{"key":"b9-focus14787","series-title":"J Neurosurg Pediatr","first-page":"468","article-title":"Complications associated with recombinant human bone morphogenetic protein use in pediatric craniocervical arthrodesis","volume":"7","author":"Lindley","year":"2011"},{"key":"b10-focus14787","author":"Mazur"},{"key":"b11-focus14787","series-title":"J Neurosurg 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