{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,7]],"date-time":"2026-08-07T17:56:19Z","timestamp":1786125379828,"version":"build-2736575974"},"reference-count":10,"publisher":"Ovid Technologies (Wolters Kluwer Health)","issue":"2","license":[{"start":{"date-parts":[[2019,11,26]],"date-time":"2019-11-26T00:00:00Z","timestamp":1574726400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/journals\/pages\/open_access\/funder_policies\/chorus\/standard_publication_model"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Operative Surg.","ONSURG"],"published-print":{"date-parts":[[2020,8]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>BACKGROUND<\/jats:title>\n                    <jats:p>Occipitocervical instability may result from transcondylar resection of the occipital condyle. Initially, patients may be able to maintain a neutral alignment but severe occipitoatlantal subluxation may subsequently occur, with cranial settling, spinal cord kinking, and neurological injury.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>OBJECTIVE<\/jats:title>\n                    <jats:p>To evaluate the ability of posterior fixation constructs to prevent progression to severe deformity after radical unilateral condylectomy.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>METHODS<\/jats:title>\n                    <jats:p>Eight human cadaveric specimens (Oc-C2) underwent biomechanical testing to compare stiffness under physiological loads (1.5 N m). A complete unilateral condylectomy was performed to destabilize one Oc-C1 joint, and the contralateral joint was left intact. Unilateral Oc-C1 or Oc-C2 constructs on the resected side and bilateral Oc-C1 or Oc-C2 constructs were tested.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>RESULTS<\/jats:title>\n                    <jats:p>The bilateral Oc-C2 construct provided the greatest stiffness, but the difference was only statistically significant in certain planes of motion. The unilateral constructs had similar stiffness in lateral bending, but the unilateral Oc-C1 construct was less stiff in axial rotation and flexion-extension than the unilateral Oc-C2 construct. The bilateral Oc-C2 construct was stiffer than the unilateral Oc-C2 construct in axial rotation and lateral bending, but there was no difference between these constructs in flexion-extension.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>CONCLUSION<\/jats:title>\n                    <jats:p>Patients who undergo a complete unilateral condylectomy require close surveillance for occipitocervical instability. A bilateral Oc-C2 construct provides suitable biomechanical strength, which is superior to other constructs. A unilateral construct decreases abnormal motion but lacks the stiffness of a bilateral construct. However, given that most patients undergo a partial condylectomy and only a small proportion of patients develop instability, there may be scenarios in which a unilateral construct may be appropriate, such as for temporary internal stabilization.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1093\/ons\/opz341","type":"journal-article","created":{"date-parts":[[2019,11,26]],"date-time":"2019-11-26T03:50:41Z","timestamp":1574740241000},"page":"157-164","source":"Crossref","is-referenced-by-count":4,"title":["Restabilization of the Occipitocervical Junction After a Complete Unilateral Condylectomy: A Biomechanical Comparison of Unilateral and Bilateral Fixation Techniques"],"prefix":"10.1227","volume":"19","author":[{"given":"Ilyas M","family":"Eli","sequence":"first","affiliation":[{"name":"Department of Neurosurgery, Clinical Neurosciences Center, University of Utah, Salt Lake City, Utah"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael","family":"Karsy","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Clinical Neurosciences Center, University of Utah, Salt Lake City, Utah"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Darrel S","family":"Brodke","sequence":"additional","affiliation":[{"name":"Department of Orthopaedics, University of Utah, Salt Lake City, Utah"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kent N","family":"Bachus","sequence":"additional","affiliation":[{"name":"Department of Orthopaedics, University of Utah, Salt Lake City, Utah"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"William T","family":"Couldwell","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Clinical Neurosciences Center, University of Utah, Salt Lake City, Utah"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrew T","family":"Dailey","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Clinical Neurosciences Center, University of Utah, Salt Lake City, Utah"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8510-0139","authenticated-orcid":false,"given":"Marcus D","family":"Mazur","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Clinical Neurosciences Center, University of Utah, Salt Lake City, Utah"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"276","published-online":{"date-parts":[[2020,8]]},"reference":[{"issue":"5","key":"bib1-20231031","doi-asserted-by":"crossref","first-page":"824","DOI":"10.3171\/jns.2000.92.5.0824","article-title":"Quantitative description of the far-lateral transcondylar transtubercular approach to the foramen magnum and clivus","volume":"92","author":"Spektor","year":"2000","journal-title":"J 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craniocervical approach: anatomical study and clinical analysis of 69 patients","volume":"90","author":"Salas","year":"1999","journal-title":"J Neurosurg"},{"issue":"1","key":"bib9-20231031","doi-asserted-by":"crossref","first-page":"140","DOI":"10.1093\/neuros\/nyw002","article-title":"Occipitocervical instability after far-lateral transcondylar surgery: a biomechanical analysis","volume":"80","author":"Mazur","year":"2017","journal-title":"Neurosurgery"},{"issue":"4","key":"bib10-20231031","doi-asserted-by":"crossref","first-page":"E9","DOI":"10.3171\/2015.1.FOCUS14787","article-title":"Unilateral fixation for treatment of occipitocervical instability in children with congenital vertebral anomalies of the craniocervical junction","volume":"38","author":"Mazur","year":"2015","journal-title":"Neurosurg Focus"}],"container-title":["Operative 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