Introduction: Patients with Adult Spinal Deformity (ASD) that undergo operative treatment may have varying degrees of improvement in patient reported outcomes. The Oswestry Disability Index (ODI) is utilized to assess improvements in quality of life following surgery. We aim to measure longitudinal outcomes of ODI scores over 3 years to determine if early ODI scores are predictive of late ODI scores, and to analyze the degree of change in ODI scores over time.
Methods: Patients above age 18 who underwent surgery for ASD at a large medical center from 2016 to 2022 and completed ODI questionnaires at follow-up appointments met inclusion criteria. ODI scores from follow-up visits at the defined time periods of 0 months (immediately post-op) and within +/-1 month of 6, 12, 18, 24, 30, and 36 months were included. Percent change in ODI from 0 months was calculated and unpaired t-tests were conducted.
Results: ODI scores increased by 8.8% at 0 months, and percent change from preoperative ODI scores at each subsequent visit were as follows: -11.1% at 3 months, -21.4% at 6 months, -25.4% at 12 months, -28% at 18 months, -31.3% at 24 months, -25.7% at 30 months, and –36.5% at 36 months. ODI scores at each follow-up visit showed significant improvement from 0-month scores. There was an improvement in scores from 3 to 6 months (p=0.04), but no significant difference in 6-month interval visits following 6 months.
Conclusion : Our results demonstrate a significant and sustained improvement in ODI scores over a 3-year period following spinal surgery. ODI scores were stable following 6 months, indicating that ODI scores at 6 months may be predictive of scores up to 3 years following surgery. Examination of individual components of ODI sub-scores and comparison of ODI results to other PROMs would be valuable in future analyses.
