233. Development of risk stratification predictive models for cervical deformity surgery

Abstract

BACKGROUND CONTEXT As the field of corrective cervical deformity (CD) surgery progresses, surgeons continue to take on more challenging cases. In order to minimize suboptimal postoperative outcomes it is important to develop a tool that allows for proper preoperative risk stratification. PURPOSE Develop individualized predictive models for identification of risk-factors that lead to the development of major complications, revisions, and unplanned reoperation. STUDY DESIGN/SETTING Retrospective cohort study of a prospective adult cervical deformity database. PATIENT SAMPLE A total of 105 CD patients. OUTCOME MEASURES Major complications (prolonged hospitalization, invasive intervention, prolonged or permanent morbidity, death within 1 year[1Y]), unplanned revision or reoperation after CD surgery within 1Y, HRQOL (NDI, mJOA, EQ5D). METHODS CD patients (cervical kyphosis >10°, coronal scoliosis >10°, cSVA >4cm, TS-CL >10°, or CBVA >25°) ≥18 years old with complete baseline (BL), 1Y HRQoL and radiographic data. Patients were stratified into two groups based on their outcome from surgery: revision (Rev) and major complication (MC). Descriptive analysis identified cohort demographics, radiographic parameters and surgical details. Univariate analysis of preoperative and surgical factors was conducted to determine associations with any of the two outcomes. Stepwise logistic regressions identified surgical, radiographic, and HRQL factors that were associated with Rev or MC. Decision tree analysis established cut-offs for predictive variables. RESULTS A total of 105 CD patients were included (61.6yrs, 67%F, BMI: 28.4kg/m2, CCI: 0.96±1.3). Surgical details: 7.6± 3.7 levels fused; mean EBL of 816 mL. By surgical approach, 45.71% had a posterior approach, 35.24% combined approach, and 19.05% anterior approach. Radiographically at baseline, patients presented with: PT: 18.9± 11.3; PI: 53.0±11.2; PI-LL: -0.45±17.2; SVA: -4.3±66.8, TS-CL: 37.9 ±20.2; cSVA: 38.4±19.9. Postoperatively, 20 patients experienced a MC and 17 patients underwent a subsequent rev. instrumentation location (LIV: 1.1[1.0-1.3] and UIV: 1.5[1.1-2.1]) was significantly associated with undergoing a rev after index surgery (all p C3, LIV>T3, C2-T3 SVA 57.6°, CTPA>7.8°, and C2S 59.2°, C2-C7 SVA > 69.1°, C2-T3 SVA 4.25, surgical invasiveness and posterior osteotomies (AUC:0.83). CONCLUSIONS Major adverse events were not uncommon following adult cervical deformity correction. Risk stratification models were developed to predict with high accuracy the occurrence of these common significant postoperative events. Revisions were predicted with an accuracy of 80% using a predominance of radiographic variables, while the occurrence of other major complications was also predicted with high reliability utilizing additional baseline HRQoL data and surgical factors. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.