Factors associated with infection recurrence after two-stage exchange for periprosthetic hip infection

Two-stage exchange is the treatment of choice for periprosthetic joint infection (PJI). Factors and outcomes associated with infection recurrence for hip PJI are limited. The primary aim of this study was to determine factors associated with infection recurrence after two-stage exchange. Secondary aims were survival, mobility, and the EuroQol five-dimension scale (EQ-5D-5L) health state.

We retrospectively investigated patients with two-stage exchange for hip PJI at our institution from 2006 to 2017. Follow-up was conducted for a minimum of four years after the reimplantation.

We included 135 patients with 139 hip PJIs. The mean age of the patients was 69.6 years (range 32-88). The infection recurrence rate was 14.4% (n = 20) after a mean follow-up of 8.0 years (range 4.0-13.1). Four factors for recurrence were identified at the time of the first stage: previous orthopaedic diagnoses (p < 0.001), type of explanted prosthesis (p = 0.004), cultured microorganisms (p = 0.033), and sinus tract (p = 0.035). A longer surgical reimplantation time (p = 0.015) was the only one factor found at the second stage. The estimated Kaplan-Meier survival for the total sample was 9.0 years (95% confidence interval 8.3-9.8), without significant difference for those with infection recurrence compared to recurrence-free patients (log-rank 0.931). At the time of follow-up, 89 patients were alive. For these patients, Parker mobility score (p = 0.102), EuroQol five-dimensional scale (p = 0.099), and EQ Visual Analogue Scale (EQ-VAS) (p = 0.027) were inferior in those with infection recurrence, but significance was found only for VAS.

In this study with mid- to long-term follow-up, five factors for infection recurrence were identified. Recurrence did not affect survival, but health-related quality of life was inferior compared to recurrence-free patients. The results suggest that the period of the first stage including previous orthopaedic diagnoses requires more consideration in the future.