{"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":1791617082374,"version":"4.3.4"},"reference-count":25,"publisher":"Journal of Neurosurgery Publishing Group (JNSPG)","issue":"4","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2022,10,1]]},"abstract":"<jats:sec>\n<jats:title>OBJECTIVE<\/jats:title>\n<jats:p>Hyperextension of C0\u20132 is a debilitating compensatory mechanism used to maintain horizontal gaze, analogous to high pelvic tilt in the lumbopelvic complex to maintain an upright posture. This study aims to investigate the impact of cervical deformity (CD) correction on this hyperextension. The authors hypothesize that correction of cervical sagittal malalignment allows for relaxation of C0\u20132 hyperextension and improved clinical outcomes.<\/jats:p>\n<\/jats:sec>\n<jats:sec>\n<jats:title>METHODS<\/jats:title>\n<jats:p>A retrospective review was conducted of a multicenter database of patients with CD undergoing spinal realignment and fusion caudal to C2 and cephalad to the pelvis. Range of motion (ROM) and reserve of extension (ROE) were calculated across C2\u20137 and C0\u20132. The association between C2\u20137 correction and change in C0\u20132 ROE was investigated while controlling for horizontal gaze, followed by stratification into \u0394C2\u20137 percentiles.<\/jats:p>\n<\/jats:sec>\n<jats:sec>\n<jats:title>RESULTS<\/jats:title>\n<jats:p>Sixty-five patients were included (mean age 61.8 \u00b1 9.6 years, 68% female). At baseline, patients had cervical kyphosis (C2\u20137, \u221211.7\u00b0 \u00b1 18.2\u00b0; T1 slope\u2013cervical lordosis mismatch, 38.6\u00b0 \u00b1 18.6\u00b0), negative global alignment (sagittal vertical axis [SVA] \u221212.8 \u00b1 71.2 mm), and hyperlordosis at C0\u20132 (mean 33.2\u00b0 \u00b1 11.8\u00b0). The mean ROM was 25.7\u00b0 \u00b1 17.7\u00b0 and 21.3\u00b0 \u00b1 9.9\u00b0 at C2\u20137 and C0\u20132, respectively, with an ROE of approximately 9\u00b0 for each segment. Limited C0\u20132 ROM and ROE correlated with the Neck Disability Index (r = \u22120.371 and \u22120.394, p &lt; 0.01). The mean number of levels fused was 7.0 \u00b1 3.1 (24.6% anterior, 43.1% posterior), with 87.7% undergoing at least an osteotomy. At 1 year, mean C2\u20137 increased to 5.5\u00b0 \u00b1 13.4\u00b0, SVA became neutral (11.5 \u00b1 54.8 mm), C0\u20132 hyperlordosis decreased to 27.8\u00b0 \u00b1 11.7\u00b0, and thoracic kyphosis (TK) increased to \u221249.4\u00b0 \u00b1 18.1\u00b0 (all p &lt; 0.001). Concurrently, mean C0\u20132 ROM increased to 27.6\u00b0 \u00b1 8.1\u00b0 and C2\u20137 ROM decreased significantly to 9.0\u00b0 \u00b1 12.3\u00b0 without a change in ROE. Controlling for horizontal gaze, change in C2\u20137 lordosis significantly correlated with increased TK (r = \u22120.617, p &lt; 0.001), decreased C0\u20132 (r = \u22120.747, p &lt; 0.001), and increased C0\u20132 ROE (r = 0.550, p = 0.002).<\/jats:p>\n<\/jats:sec>\n<jats:sec>\n<jats:title>CONCLUSIONS<\/jats:title>\n<jats:p>CD correction can significantly impact cephalad and caudal compensation in the upper cervical and thoracic spine. Restoration of cervical alignment resulted in increased C0\u20132 ROE and TK and was also associated with improved clinical outcome.<\/jats:p>\n<\/jats:sec>","DOI":"10.3171\/2022.2.spine211316","type":"journal-article","created":{"date-parts":[[2022,5,13]],"date-time":"2022-05-13T07:20:23Z","timestamp":1652426423000},"page":"599-606","source":"Crossref","is-referenced-by-count":9,"title":["Proximal and distal reciprocal changes following cervical deformity malalignment correction"],"prefix":"10.3171","volume":"37","author":[{"given":"Renaud","family":"Lafage","sequence":"first","affiliation":[{"name":"Department of Orthopedics, Hospital for Special Surgery, New York, New York;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Justin S.","family":"Smith","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, University of Virginia Medical Center, Charlottesville, Virginia;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alex Moy","family":"Fong","sequence":"additional","affiliation":[{"name":"Department of Orthopedics, Hospital for Special Surgery, New York, New York;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Basel","family":"Sheikh Alshabab","sequence":"additional","affiliation":[{"name":"Department of Orthopaedic Surgery, Northwell Health, Lenox Hill Hospital, New York, New York;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Themistocles","family":"Protopsaltis","sequence":"additional","affiliation":[{"name":"Department of Orthopedics, NYU Langone Orthopedic Hospital, New York, New York;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eric O.","family":"Klineberg","sequence":"additional","affiliation":[{"name":"Department of Orthopaedic Surgery, University of California, Davis, Sacramento, California;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gregory","family":"Mundis","sequence":"additional","affiliation":[{"name":"Scripps Clinic, San Diego, California;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Peter G.","family":"Passias","sequence":"additional","affiliation":[{"name":"Department of Orthopedics, NYU Langone Orthopedic Hospital, New York, New York;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Munish","family":"Gupta","sequence":"additional","affiliation":[{"name":"Department of Orthopaedics, Washington University, St. Louis, Missouri;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christopher I.","family":"Shaffrey","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Duke University Medical Center, Durham, North Carolina;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Han Jo","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Orthopedics, Hospital for Special Surgery, New York, New York;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shay","family":"Bess","sequence":"additional","affiliation":[{"name":"Denver International Spine Center, Presbyterian St. Luke\u2019s\/Rocky Mountain Hospital for Children, Denver, Colorado; and"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Frank","family":"Schwab","sequence":"additional","affiliation":[{"name":"Department of Orthopaedic Surgery, Northwell Health, Lenox Hill Hospital, New York, New York;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christopher P.","family":"Ames","sequence":"additional","affiliation":[{"name":"Department of Neurological Surgery, University of California, San Francisco, School of Medicine, San Francisco, California"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Virginie","family":"Lafage","sequence":"additional","affiliation":[{"name":"Department of Orthopaedic Surgery, Northwell Health, Lenox Hill Hospital, New York, New York;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"_","family":"_","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1754","reference":[{"issue":"10","key":"b1","series-title":"Clin Spine Surg","doi-asserted-by":"publisher","first-page":"413","DOI":"10.1097\/BSD.0000000000000743","article-title":"Cervical versus thoracolumbar spinal deformities: a comparison of baseline quality-of-life burden","volume":"31","author":"Passias PG","year":"2018","unstructured":"Passias PG, Poorman GW, Lafage V,  Cervical versus thoracolumbar spinal deformities: a comparison of baseline quality-of-life burden. 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