Supplementary Material for: Effect of Bunion Surgery on Fall Risk: A Nationwide Database Study of 127,990 Older Adults with Hallux Valgus

Introduction: The presence of a bunion (hallux valgus) deformity is a recognized risk factor for falls among older adults; however, it is uncertain whether surgical correction of the foot deformity can help mitigate this risk.
Methods: We conducted a retrospective cohort study of US adults aged 50 and over with hallux valgus using commercial, state, and federal healthcare claims obtained from a national database (PearlDiver, Inc.). Patients who underwent bunion surgery were compared to those treated nonoperatively for their bunion deformities from January 2011 to April 2022. Claims-based falls (all-cause) were tracked using diagnosis codes for up to 11 years. Group differences in fall risk were examined using both one-year and long-term adjusted hazard ratios (aHR) and corresponding absolute risks.
Results: 127,990 people were diagnosed with hallux valgus and 17,406 (13.6%) underwent surgery. The median follow-up time was 2905 and 2298 days for the surgery and non-surgery groups, respectively. A smaller proportion of people fell in the surgery versus non-surgery group (5 vs 8% at one year; 16 vs 21% over total follow-up). Furthermore, after controlling for important covariates, patients who underwent bunion surgery were 16% less likely to fall in the first year (aHR 0.84, 95% CI 0.76 to 0.92) and 42% less likely to fall over the 11-year follow-up (aHR 0.58, 95% CI 0.52 to 0.63) compared to those with uncorrected hallux valgus deformity.
Conclusion: Among older adults in whom surgery is already indicated, a potential ancillary benefit may be a reduction in injurious falls over time.