Barn theatres and conventional theatres: a non-inferiority analysis of hip fracture arthroplasty outcomes

INTRODUCTION: Hip fractures represent a major health burden in the elderly. The increasingly adopted "barn" theatre model, characterised by open-plan operating space, aims to improve surgical efficiency, but its safety in trauma remains unreported. This study analyses whether barn theatres are non-inferior to conventional theatres for hip fracture arthroplasty outcomes. METHODS: We undertook a retrospective, single-centre, cohort study in a high-volume UK trauma unit, comparing consecutive patients undergoing arthroplasty for femoral neck fracture before and after barn theatre implementation (May 2022 to December 2023). The primary outcome was 30-day all-cause mortality, with a non-inferiority margin of +2.5 percentage points. Secondary outcomes included 1-year mortality, 30-day readmission, reoperation and length of stay (LOS). Outcomes were adjusted for age, American Society of Anesthesiologists' grade and Charlson Comorbidity Index, and were benchmarked against National Hip Fracture Database (NHFD) standards. RESULTS: In total, 475 patients were included (238 pre-barn, 237 post-barn). Groups were demographically similar, although Charlson scores were higher post-barn. Adjusted odds ratio (aOR) for 30-day mortality in barn vs conventional theatres was 0.77 (95% confidence interval [CI] 0.36-1.71), meeting non-inferiority criteria. One-year mortality (aOR 1.10, 95% CI 0.66-1.82), readmission (aOR 0.83, 95% CI 0.45-1.54) and reoperation (aOR 1.06, 95% CI 0.39-2.89) showed no significant differences. Mortality and readmission outcomes were comparable with NHFD benchmarks, while post-barn LOS was shorter (median 12 vs 13 days). CONCLUSION: Barn theatres were non-inferior to conventional theatres for hip fracture arthroplasty, producing mortality and complication rates within national standards while demonstrating potential efficiency gains. These findings support barn theatres as a safe and scalable model for trauma surgery, although multicentre studies are warranted to confirm generalisability.