RT Journal Article SR Electronic T1 Development of New-Onset Cervical Deformity in Nonoperative Adult Spinal Deformity Patients With 2-Year Follow-Up JF International Journal of Spine Surgery JO Int J Spine Surg FD International Society for the Advancement of Spine Surgery SP 725 OP 734 DO 10.14444/5091 VO 12 IS 6 A1 PETER G. PASSIAS A1 CYRUS M. JALAI A1 NANCY WORLEY A1 SHALEEN VIRA A1 JUSTIN K. SCHEER A1 JUSTIN S. SMITH A1 SUBARAMAN RAMACHANDRAN A1 ALEXANDRA SOROCEANU A1 SAMANTHA R. HORN A1 GREGORY W. POORMAN A1 THEMISTOCLES S. PROTOPSALTIS A1 ERIC O. KLINEBERG A1 DANIEL M. SCIUBBA A1 HAN JO KIM A1 D. KOJO HAMILTON A1 RENAUD LAFAGE A1 VIRGINIE LAFAGE A1 CHRISTOPHER P. AMES A1 INTERNATIONAL SPINE STUDY GROUP (ISSG) YR 2018 UL http://ijssurgery.com//content/12/6/725.abstract AB Purpose: Evaluate the presence of new-onset cervical deformity (CD) in nonoperative adult spinal deformity (ASD) patients with extended follow-up, with consideration for predictors, prevalence, and impact on patient-reported outcomes. Methods: Retrospective review of a prospective nonoperative ASD cohort. New onset CD patients at 1- (CD-1Y) and 2-year (CD-2Y) follow-up were defined as displaying baseline cervical alignment. Univariate analyses determined differences in radiographic parameters and outcome scores of CD and maintained-cervical-alignment patients. Multivariate binary logistic regression models determined new-onset CD predictors.Results: A total of 143 patients were included (mean age 54 years, mean body mass index 25.6 kg/m2, 86% female). Cervical deformity rate was 38.5% at baseline. New-onset CD incidence at 1- and 2-year follow-up was 30.0% and 41.7%, respectively. Global sagittal profile comparison of CD-1Y/CD-2Y versus maintained cervical alignment cases revealed no differences (P > .05) at any interval. Baseline C2-C7 sagittal vertical axis (SVA) was associated with increased new-onset CD risk at 1 (odds ratio [OR] 1.14, P = .025) and 2 years (OR 1.04, P = .032); prior spine surgical history was associated with CD risk at 1-year follow-up (OR 6.75, P = .047); baseline C2 slope was associated with increased CD risk at 2-year follow-up (OR 1.12, P = .041). CD development did not significantly impact health-related quality of life (P > .05). Conclusions: Cervical deformity can manifest in nonoperative ASD patients: 30.0% at 1-year follow-up, and 41.7% at 2-year follow-up. Progressive CD manifested independently of thoracolumbar profile changes. Increased baseline C2-C7 SVA, C2 slope, and prior surgical history increased new-onset CD odds at 1 and 2 years.