Cost-effectiveness of surgical and conservative interventions for orthopaedic injuries in Malawi: a modelling study.

BACKGROUND: Orthopaedic injuries are a major contributor to morbidity and mortality in low-income settings, driven by rising urbanisation and inadequate road safety measures. This study evaluates the cost-effectiveness of treatment for four common orthopaedic injuries in Malawi: femoral shaft fractures, patellar fractures, humeral shaft fractures and paediatric supracondylar humeral fractures (PSCHF). METHODS: We developed a dynamic state-transition model to simulate fatal and non-fatal outcomes from a healthcare perspective from 2021 to 2031, informed by cost, epidemiological and population estimates. We estimated incremental cost-effectiveness ratios (ICER) for conservative and surgical management versus no treatment and each other, conducting one-way and probabilistic sensitivity analyses. We then modelled the population impact of scaling up the most cost-effective intervention under two scenarios. FINDINGS: For femoral shaft fractures, surgical, conservative and no treatment resulted in disability-adjusted life years (DALYs) of 0.10, 0.21 and 0.23, with ICERs of approximately US$3000 and US$60 000 for surgical and conservative treatment. For patellar fractures, DALYs were 0.20, 0.22 and 0.32, with similar cost-effectiveness (ICERs of US$1400). For humeral shaft fractures, DALYs were 0.041, 0.056 and 0.11, with ICERs of US$3000 and US$1400. For PSCHF, DALYs were 0.04, 0.086 and 0.14, with ICERs of US$1600 and US$2600. Comparison of surgical and conservative strategies shows surgery was cost-saving for femoral shaft fractures, similar for patellar fractures, less efficient for humeral shaft fractures and more cost-effective for PSCHF. At Malawi's willingness-to-pay threshold of US$65 per DALY averted, the probability of cost-effectiveness was low. Under the ambitious scale-up scenario, approximately 1800 DALYs (a 10% reduction relative to the baseline) were averted at an incremental cost of US$5 million. CONCLUSION: In Malawi, surgery is more cost-effective for femoral shaft and PSCHF fractures, whereas conservative care is more cost-effective for humeral shaft fractures. For patella fractures with an intact extensor mechanism, both treatments are similarly cost-effective. Targeted scale-up could yield substantial health gains, underscoring the importance of context-specific data for prioritising orthopaedic services in low-resource settings.