The effect of COVID-19 lockdown restrictions on oswestry disability index scores: a comparative cross-sectional study

PURPOSE: Lockdown measures to combat the COVID-19 pandemic restricted social interactions and travel. This retrospective, observational study was conducted to evaluate the effect of lockdown restrictions on Oswestry Disability Index (ODI) scores in patients with spinal conditions. METHODS: Prospectively collected data from the British Spine Registry were retrospectively analysed in two groups. The study group included patients' baseline pre-operative ODI scores collected during the first national lockdown in the UK between March and May 2020. The reference group included ODI scores recorded during the same period in 2019, before the pandemic. Scores were compared between groups using the Mann–Whitney U test. We also calculated modified scores that omitted responses to questions related to travel and social life. These were compared using Wilcoxon matched-pairs signed-rank test and Bland–Altman analyses. RESULTS: The median ODI scores for the reference and lockdown groups were 49 and 45, respectively, with no significant differences in the mean ranks (p = 0.068). Comparisons of original and modified ODI scores showed different outcomes for each study group. No significant differences were observed in the lockdown group (p = 0.06). However, for the pre-COVID-19 reference group, there was a significant difference (p < 0.01). Bland–Altman analyses showed reasonable agreement between the methods for calculating ODI in both groups. CONCLUSION: We found no clinically important differences in ODI scores between the two groups. The findings suggest that the ODI is reliable during lockdown situations and can be used with confidence in the future research using both retrospective and prospective data. LEVEL OF EVIDENCE: Level 3.