497 Does Physical Activity Improve Patient Outcomes Following Lumbar Microdiscectomy?

Abstract

INTRODUCTION: Lumbar microdiscectomy is widely performed for disc herniation, however outcomes may be unsatisfactory in 10-40% patients and up to 12.5% require re-operation. Evidence regarding the effect of physical activity on post-operative outcomes is scant. The majority of existing studies rely on biased activity self-reporting or short-term monitoring. Duration of physical activity presents a tangible goal for patient counselling, can be measured using wearable technology, and can be targeted to improve outcomes. METHODS: 53 patients underwent lumbar microdiscectomy and wore an accelerometer for 30 days post-operatively, which measured activity duration (lying, sitting, standing, walking, cycling) and intensity. Patient-reported outcome scores (VASB, VASL, ODI, EQ-5D, SF-12) at 1, 3, 6, and 12 months, and activity data were analysed. The primary outcome (treatment success) was a predetermined reduction in VASB, VASL, and ODI. The relationship between treatment success and activity was assessed using the Mann-Whitney U test. Associations between outcomes and activity were investigated using MANOVA and Pearson Correlations. RESULTS: Longer standing time was associated with worse ODI scores at 6 months (p = .034). There was no other statistically significant association between treatment success and activity duration or intensity. MANOVA demonstrated that shorter sitting time was associated with less back pain at 3 (p = .01) and 12 months (p = .011). Univariate analysis revealed that longer walking time was associated with improved EQ-5D scores at 3 (p = .001) and 12 months (p = .034), and improved SF-12 physical scores at 3 months (p = .026). CONCLUSIONS: Shorter standing time was associated with less disability, shorter sitting time with less back pain, and longer walking time with improved physical wellbeing after lumbar microdiscectomy. Higher-powered studies are needed to further explore the relationship between physical activity and outcomes.