Risk of Re-Infection Following One- And Two-Stage Surgical Revision of Peri-Prosthetic Joint Infection of the Hip: A Pooled Individual Participant Data Analysis of 44 Observational Cohort

Background: One-stage and two-stage revision strategies are the two main options for treating established peri-prosthetic joint infection (PJI) of the hip; however, there is uncertainty regarding which is the best treatment option. We aimed to examine re-infection rates among patients with PJI of the hip who have undergone one- or two stage revision and compare the risk of re-infection between the two revision strategies using pooled individual participant data (IPD).

Methods: Observational cohort studies with PJI of the hip treated exclusively by one- or two-stage revision and reporting re-infection outcomes were retrieved by searching online data; as well as manual search of bibliographies and email contact with investigators. Investigators were invited to contribute individual level data. We analysed IPD of 1,856 participants with PJI of the hip from 44 cohorts across four continents. The primary outcome was re-infection (recurrence of infection by the same organism(s) and/or re-infection with a new organism(s)). Hazard ratios (HRs) for re-infection were calculated using Cox proportional frailty hazards models.

Results: After a median follow-up of 3.7 years, 222 re-infections were recorded. Re-infection rates per 1000 person-years of follow-up were 16.8 (95% CI: 13.6-20.7) and 32.3 (95% CI: 27.3-38.3) for one-stage and two-stage strategies respectively. Among 1,038 individuals with available survival data, comparing two- with one-stage revision, the age-adjusted HR for re-infection was 1.69 (0.58-4.98). The corresponding age- and sex-adjusted HR was 1.70 (0.58-5.00). The association remained consistently absent after further adjustment for potential confounders. Conversely, the HRs were not significant when comparing one- with two-stage revision. HRs did not vary importantly in clinically relevant subgroups

Conclusion: Pooled available data suggest no statistically significant increased risk of re-infection comparing the two-stage with one-stage revision strategy and vice versa. The one-stage revision strategy may be as effective as the two-stage revision strategy in treating PJI of the hip in generally unselected patients.