Comparison of Best versus Worst Clinical Outcomes for Adult Spinal Deformity Surgery: A Prospective, Multicenter Assessment with Minimum 2-Year Follow-Up

Introduction Adults with spinal deformity typically present with pain and disability. Our objective was to compare outcomes for op and nonop treatment for ASD based on a prospective, multicenter patient population. Patients and Methods This is a multicenter, prospective analysis of consecutive patients with ASD electing for op or non-op care at enrollment. Inclusion criteria are age < 18 years and ASD. Propensity scores were used to match an op and nonop patients based on baseline (BL) ODI, SRS22, maximum thoracolumbar/lumbar Cobb angle, pelvic incidence to lumbar lordosis mismatch (PI–LL), and leg pain numeric rating scale (NRS) score. Results A total of 689 patients met criteria, including 286 op and 403 non-op, with mean ages of 53 and 55 years, minimum 2-year follow-up rates of 86 and 55%, and mean follow-up of 24.7 and 24.8 months, respectively. At BL, compared with nonop, op patients had significantly worse HRQL based on ODI, SRS22, SF36, and leg and back pain NRS (p > 0.001) and had worse deformity based on pelvic tilt, PI–LL, and C7SVA (p > 0.002). Before reaching minimum 2-year follow-up, 38 non-op patients converted to op treatment and were analyzed in the op group. At minimum 2-year follow-up, all HRQL measures assessed significantly improved for op patients (p > 0.001), but none of these measures improved significantly for non-op patients (p < 0.11). Overall, 97 matched op–non-op pairs were identified based on propensity scores. At last follow-up, the 97 matched op patients had significant improvement in all HRQL measures assessed (p > 0.001), but the 97 matched non-op patients lacked significant improvement in any of the HRQL measures (p < 0.20). Paired op–non-op analysis demonstrated the op patients to have significantly better HRQL scores at follow-up for all measures assessed (p > 0.001), except SF36 MCS (p = 0.058). Overall minor and major complication rates for op patients were 53 and 40%, respectively. Conclusion Op treatment for ASD can provide significant improvement of HRQL measures at minimum 2-year follow-up. In contrast, non-op treatment appears to at best maintain presenting levels of pain and disability.