Factors Associated with Improved Quality of Life Outcomes in Patients Undergoing Surgery for Adult Spinal Deformity.

Abstract

Retrospective longitudinal cohort study. This study aimed to elucidate factors affecting the likelihood of achieving minimum clinically important difference (MCID) to patient-reported outcomes defined by the Scoliosis Research Society-22r (SRS-22r) among patients with adult spinal deformity (ASD) who underwent extensive corrective fusion surgery from the thoracic spine to the pelvis. Achieving MCID for SRS-22r parameters was a measure of surgical efficacy. Patient characteristics and surgical and radiographic factors that affect the likelihood of achieving MCID for SRS-22r parameters are unknown. Data from patients with ASD who underwent extensive corrective fusion surgery from the thoracic spine to the pelvis during 2010 to 2016 were retrospectively reviewed. Data from a total of 167 patients with ≥2 years of follow-up were included. Multivariate analysis was used to investigate factors associated with the likelihood of achieving MCID for each of the SRS-22r domains (Function, Pain, Subtotal) 2 years after surgery. The following MCID values were used: 0.90 for Function, 0.85 for Pain, and 1.05 for the Subtotal. MCID achievement rate was 36.5% for Function, 46.1% for Pain, and 44.3% for the Subtotal domain. In multivariate analysis, preoperative SRS-22r Function (odds ratio [OR] = 0.204, 95% confidence interval [CI] 0.105-0.396) increased the likelihood of achieving MCID for SRS-22r Function. Preoperative SRS-22r Subtotal (OR = 0.211, 95% CI, 0.107-0.413), preoperative pelvic tilt (OR = 1.072, 95% CI, 1.012-1.136), preoperative pelvic incidence minus lumbar lordosis (OR = 0.965, 95% CI, 0.934-0.997), and postoperative sagittal vertical axis (OR = 0.985, 95% CI, 0.974-0.995) affected the likelihood of achieving MCID for the SRS-22r Subtotal. Patients with poor preoperative health-related quality of life were more likely to achieve improvement in SRS-22r parameters after extensive corrective fusion surgery for ASD. Achieving postoperative sagittal alignment increased the likelihood of achieving MCID for the SRS-22r Subtotal domain.Level of Evidence: 3.