Does the Implementation of the PRO-IMPLANT Foundation Treatment Algorithm Improve the Outcome of Chronic Periprosthetic Knee Infections? Mid-Term Results of a Prospective Study.

Background: Several treatment options for chronic periprosthetic joint infections have been published in the current literature, with an on-going discussion to determine effective management algorithms.

Objectives: To compare outcomes of the two-stage exchange procedure in revision TKA prior to and after implementation of the PRO-IMPLANT Foundation treatment algorithm. The primary endpoints were defined as (i) revisions during the interval time, (ii) duration of the interval time and (iii) successful PJI eradication.

Material and methods: Between 02/2013 and 09/2016, 122 patients were included in a single-centre cohort analysis. 55 patients were treated according to the previously used algorithm (K1) and 67 according to the PRO-IMPLANT Foundation algorithm (K2). A minimum follow-up period of 3 years was set as the inclusion criterion. Successful eradication of infection was defined in accordance with the consensus criteria by Diaz-Ledezma et al. RESULTS: Successful eradication was achieved in 42 (67%) patients in K1 and 47 (85.5%) in K2 (p ≤ 0.005). The mean interval time was 88 days (range 51 - 353) in K1 and 52 days (range 42 - 126) in K2 (p ≤ 0.005). In K1, a mean of 0.8 (range 0 - 6) revisions were necessary during the interval period compared with 0.5 (range 0 - 4) in K2 (p = 0.066).

Conclusion: Implementation of the PRO-IMPLANT treatment algorithm led to significant improvement in the outcome of periprosthetic joint infections. During mid-term follow-up, infection eradication was highly successful, with decreases in the interval time as well as the number of revisions.