P127. Use of osteotomy techniques in cervical deformity procedures: Are approaches and practices changing over the years?

Abstract

<h3>BACKGROUND CONTEXT</h3> Cervical deformity (CD) corrective procedures are ever-evolving, along with the field of spine surgery. The goal of this study was to examine whether surgical advancements over the years have improved or changed outcomes, and the overall way in which we approach CD surgery. <h3>PURPOSE</h3> To investigate if operative approach and outcomes of CD have changed over time in respect to surgical advancements. <h3>STUDY DESIGN/SETTING</h3> Retrospective cohort study of a prospective cervical deformity database. <h3>PATIENT SAMPLE</h3> A total of 123 CD patients (≥18 years) with complete BL and 2Y HRQL and radiographic data were included. Descriptive analysis included demographics, radiographic, and surgical details. Patients were stratified into 2 groups based on DOS: early (Group I-2012-2014) and later (Group II-2015-2019). Osteotomies were grouped using grading by Ames et al. into low grade (LGO): Grade 1 & 2, and high grade (HGO): Grade 6 & 7. UVA and MVA analyzed differences in osteotomy usage and radiographic, surgical and clinical parameters. Significant CD was characterized by extension XR TS-CL >17°. Rigid deformity was defined by a change of <10°difference between flexion and extension XR. <h3>OUTCOME MEASURES</h3> Complications, HRQL (NDI, mJOA, EQ5D). <h3>METHODS</h3> CD patients (≥18 years) with complete BL and 2-year HRQL and radiographic data were included. Descriptive analysis included demographics, radiographic, and surgical details. Patients were stratified into 2 groups based on DOS: early (Group I-2012-2014) and later (Group II-2015-2019). Osteotomies were grouped using grading by Ames et al. into low grade (LGO): Grade 1 & 2, and high grade (HGO): Grade 6 & 7. UVA and MVA analyzed differences in osteotomy usage and radiographic, surgical and clinical parameters. Significant CD was characterized by extension XR TS-CL >17°. Rigid deformity was defined by a change of <10°difference between flexion and extension XR. <h3>RESULTS</h3> There were 123 CD patients that met inclusion criteria (61years, 63%F, 29.0kg/m2, CCI: 1±1.4). Radiographically at baseline, patients presented with: PT: 19.6± 11°; PI: 55±13°; PI-LL: .9±17.4°; SVA:-3±68mm, TS-CL: 39 ±21°; cSVA: 45±26. Surgical details were 7.7± 4 levels fused with a mean EBL of 1031mL. By surgical approach, 46% had a posterior approach, 20% anterior, and 37% combined. Group I had 49 patients, and Group II had 74. Group II had a higher CCI (1.1 vs .8, p=.2) while there were no significant differences in number of levels fused, reoperations, DJK development, or HRQL metrics between groups (p>0.05). Overall, 53% of patients had an osteotomy. Patients in Group II had a lower usage of HGO (9% vs 23%, p<0.05). In patients with significant CD, Group II received less HGO (3% vs 33%, p<0.05). In posterior approaches, controlling for age, BL deformity, and CCI, Group II underwent less HGO .32[.08-1.2] p=.1. Controlling for age, CCI, and BL deformity, Group II had lower usage of HGO in rigid deformity (.197[.04-.97], p<0.05). <h3>CONCLUSIONS</h3> Overtime, patients undergoing cervical deformity surgery received less high-grade osteotomies, even with high grade deformities. Despite operating on a cohort with a greater degree of comorbidity, there was no deterioration in clinical and radiographic outcomes. These findings reflect a better understanding of surgical management and the utility of invasive osteotomies in adult cervical deformity. <h3>FDA DEVICE/DRUG STATUS</h3> This abstract does not discuss or include any applicable devices or drugs.