208. Predictors of superior recovery kinetics in adult cervical deformity correction: an analysis using a novel area under the curve methodology

Abstract

BACKGROUND CONTEXT Novel analyses of clinical outcomes following cervical deformity (CD) corrective surgery use an area-under-the-curve (AUC) method to assess health-related quality of life (HRQL) metrics throughout the surgical recovery process. It remains unclear how demographics, preop parameters, and surgical decisions are associated with superior recovery. PURPOSE Identify demographic, surgical and radiographic factors that predict superior recovery kinetics. STUDY DESIGN/SETTING Retrospective review of a prospective CD database. PATIENT SAMPLE A total of 98 CD patients. OUTCOME MEASURES Baseline (BL) to 1-year (1Y) HRQL Instruments: Neck Disability Index (NDI). METHODS CD database criteria:C2-7 Cobb angle>10°, coronal Cobb angle >10°, cSVA>4cm or TS-CL>10°, or CBVA>25°. Following univariate analyses, the AUC normalization method was utilized by dividing all reported BL and postoperative(3M, 1Y) outcome measures by the BL score. Normalized scores(y-axis) were plotted against follow-up time interval(x-axis). Total area was calculated for all follow-up, divided by cumulative follow-up length, determining overall, time-adjusted HRQL recovery (Integrated Health State[IHS]). IHS NDI scores were stratified by quartile, the uppermost 25% were categorized as having “superior” recovery kinetics (SRK) vs “normal” recovery kinetics (NRK). BL demographic, clinical and surgical information were used to predict SRK using generalized linear modeling. RESULTS A total of 98 patients included(62±10yrs, 28±6kg/m2, 65%F). Mean CCI: 0.95, 6% smokers, and 31% history of smoking. Surgical approach: combined(33%), posterior(49%), anterior(18%). Average posterior levels fused: 8.7, anterior levels fused: 3.6, EBL: 915.9ccs, op time: 495min. According to the Ames CD classification at BL: cSVA (53.2% minor deformity and 46.8% moderate), TS-CL (9.8% minor, 4.3% moderate, 85.9% marked), and horizontal gaze (27.4% minor, 46.6% moderate, 26% marked). Relative to BL NDI scores (mean: 47), normalized postop NDI scores showed decrease in disability at 3M(0.9±0.5, p=0.260) and a further decrease at 1Y (0.78±0.41, p CONCLUSIONS Superior recovery kinetics following cervical deformity surgery was predicted with high accuracy using a combination of baseline patient reported factors(VAS EQ5D, swallow sleep, and mJOA scores) and radiographic factors(TK, T10-T12, T12-S1, L1-S1). Patients and health care providers should be aware of these factors in order to improve surgical decision-making, in an effort to reduce postop neck disability. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.