Incidence and risk factors for extended post-operative length of stay following primary hip arthroplasty in a South African setting

Background: This study sought to determine the incidence of extended post-operative length of stay (EPLoS) and its associated risk factors in South African primary hip arthroplasty patients. Methods: This was a retrospective chart review study of 185 adults who underwent primary hip arthroplasty at a quaternary South African hospital. Data related to patient, clinical, and surgical characteristics were collected. Post-operative length of stay was calculated as the time (in days) between the dates of surgery and discharge from hospital. We defined EPLoS as any length of stay ≥75th percentile obtained for the entire study population. Data were analysed using univariate and multivariate statistical methods. Results: The incidence of EPLoS was 28.1% (95% confidence interval – CI: 22.1–35.0%). Risk factors for EPLoS included: female sex (odds ratio – OR: 4.63, 95% CI: 1.74–12.34; p=0.002), patient’s maximum walking distance <100 m (OR: 3.05, 95% CI: 1.05–8.89; p=0.041) and extended duration of surgery (OR: 3.62, 95% CI: 1.31–10.01; p=0.013). Conclusion: We provide a report of EPLoS and several associated risk factors in South African primary hip arthroplasty patients. Level of evidence: Level 4