{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,10]],"date-time":"2026-10-10T07:24:42Z","timestamp":1791617082380,"version":"4.3.4"},"reference-count":19,"publisher":"Journal of Neurosurgery Publishing Group (JNSPG)","issue":"3","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2023,3,1]]},"abstract":"<jats:sec>\n<jats:title>OBJECTIVE<\/jats:title>\n<jats:p>Posterior cervical fusion is a common surgical treatment for patients with myeloradiculopathy or regional deformity. Several studies have found increased stresses at the cervicothoracic junction (CTJ) and significantly higher revision surgery rates in multilevel cervical constructs that terminate at C7. The purpose of this study was to investigate the biomechanical effects of selecting C7 versus T1 versus T2 as the lowest instrumented vertebra (LIV) in multisegmental posterior cervicothoracic fusion procedures.<\/jats:p>\n<\/jats:sec>\n<jats:sec>\n<jats:title>METHODS<\/jats:title>\n<jats:p>Seven fresh-frozen cadaveric cervicothoracic spines (C2\u2013L1) with ribs intact were tested. After analysis of the intact specimens, posterior rods and lateral mass screws were sequentially added to create the following constructs: C3\u20137 fixation, C3\u2013T1 fixation, and C3\u2013T2 fixation. In vitro flexibility tests were performed to determine the range of motion (ROM) of each group in flexion-extension (FE), lateral bending (LB), and axial rotation (AR), and to measure intradiscal pressure of the distal adjacent level (DAL).<\/jats:p>\n<\/jats:sec>\n<jats:sec>\n<jats:title>RESULTS<\/jats:title>\n<jats:p>In FE, selecting C7 as the LIV instead of crossing the CTJ resulted in the greatest increase in ROM (2.54\u00b0) and pressure (29.57 pound-force per square inch [psi]) at the DAL in the construct relative to the intact specimen. In LB, selecting T1 as the LIV resulted in the greatest increase in motion (0.78\u00b0) and the lowest increase in pressure (3.51 psi) at the DAL relative to intact spines. In AR, selecting T2 as the LIV resulted in the greatest increase in motion (0.20\u00b0) at the DAL, while selecting T1 as the LIV resulted in the greatest increase in pressure (8.28 psi) in constructs relative to intact specimens. Although these trends did not reach statistical significance, the observed differences were most apparent in FE, where crossing the CTJ resulted in less motion and lower intradiscal pressures at the DAL.<\/jats:p>\n<\/jats:sec>\n<jats:sec>\n<jats:title>CONCLUSIONS<\/jats:title>\n<jats:p>The present biomechanical cadaveric study demonstrated that a cervical posterior fixation construct with its LIV crossing the CTJ produces less stress in its distal adjacent discs compared with constructs with C7 as the LIV. Future clinical testing is necessary to determine the impact of this finding on patient outcomes.<\/jats:p>\n<\/jats:sec>","DOI":"10.3171\/2022.10.spine22381","type":"journal-article","created":{"date-parts":[[2022,12,16]],"date-time":"2022-12-16T08:32:34Z","timestamp":1671179554000},"page":"389-395","source":"Crossref","is-referenced-by-count":7,"title":["Selecting the lowest instrumented vertebra in a multilevel posterior cervical fusion across the cervicothoracic junction: a biomechanical investigation"],"prefix":"10.3171","volume":"38","author":[{"given":"Yaroslav","family":"Gelfand","sequence":"first","affiliation":[{"name":"Spine Research Group, Montefiore Medical Center\/Albert Einstein College of Medicine, Bronx, New York;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daniel","family":"Franco","sequence":"additional","affiliation":[{"name":"Department of Neurological Surgery, Thomas Jefferson University Hospitals, Sydney Kimmel College of Medicine, Philadelphia, Pennsylvania;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Merritt D.","family":"Kinon","sequence":"additional","affiliation":[{"name":"Department of Neurological Surgery, Westchester Medical Center, Valhalla, New York;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rafael","family":"De la Garza Ramos","sequence":"additional","affiliation":[{"name":"Spine Research Group, Montefiore Medical Center\/Albert Einstein College of Medicine, Bronx, New York;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Reza","family":"Yassari","sequence":"additional","affiliation":[{"name":"Musculoskeletal Education and Research Center, A Division of Globus Medical Inc., Audubon, Pennsylvania; and"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jonathan A.","family":"Harris","sequence":"additional","affiliation":[{"name":"Musculoskeletal Education and Research Center, A Division of Globus Medical Inc., Audubon, Pennsylvania; and"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Samantha","family":"Flamand","sequence":"additional","affiliation":[{"name":"Musculoskeletal Education and Research Center, A Division of Globus Medical Inc., Audubon, Pennsylvania; and"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Joshua P.","family":"McGuckin","sequence":"additional","affiliation":[{"name":"Musculoskeletal Education and Research Center, A Division of Globus Medical Inc., Audubon, Pennsylvania; and"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jorge L.","family":"Gonzalez","sequence":"additional","affiliation":[{"name":"School of Biomedical Engineering, Science and Health Systems, Drexel University, Philadelphia, Pennsylvania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jonathan M.","family":"Mahoney","sequence":"additional","affiliation":[{"name":"Musculoskeletal Education and Research Center, A Division of Globus Medical Inc., Audubon, Pennsylvania; and"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Brandon S.","family":"Bucklen","sequence":"additional","affiliation":[{"name":"Musculoskeletal Education and Research Center, A Division of Globus Medical Inc., Audubon, Pennsylvania; and"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1754","reference":[{"issue":"26","key":"b1","series-title":"Spine (Phila Pa 1976)","first-page":"2247","article-title":"Anterior versus posterior surgical approaches to treat cervical spondylotic myelopathy: outcomes of the prospective multicenter AOSpine North America CSM study in 264 patients","volume":"38","author":"Fehlings MG","year":"2013","unstructured":"Fehlings MG, Barry S, Kopjar B,  Anterior versus posterior surgical approaches to treat cervical spondylotic myelopathy: outcomes of the prospective multicenter AOSpine North America CSM study in 264 patients. 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J Bone Joint Surg Am. 2017;99(12):1013\u20131021.28632590"},{"issue":"23","key":"b4","series-title":"Spine (Phila Pa 1976)","first-page":"1845","article-title":"Is it necessary to extend a multilevel posterior cervical decompression and fusion to the upper thoracic spine?","volume":"41","author":"Schroeder GD","year":"2016","unstructured":"Schroeder GD, Kepler CK, Kurd MF,  Is it necessary to extend a multilevel posterior cervical decompression and fusion to the upper thoracic spine? Spine (Phila Pa 1976).2016;41(23):1845\u20131849."},{"issue":"4","key":"b5","series-title":"Global Spine J","first-page":"282","article-title":"Biomechanical determination of distal level for fusions across the cervicothoracic junction","volume":"5","author":"Cheng I","year":"2015","unstructured":"Cheng I, Sundberg EB, Iezza A, Lindsey DP, Riew KD. Biomechanical determination of distal level for fusions across the cervicothoracic junction. 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