Background: Two-stage exchange revision total knee arthroplasty [TKA] is the gold standard for treating a chronically infected TKA. Application of a cement-on-cement antibiotic-loaded articulating spacer in the 1st stage exchange arthroplasty provides a good functional outcome during the interim between stages, easy surgical exposure for the 2nd stage exchange revision arthroplasty, and excellent infection
eradication.

Objective: To describe the intraoperative use of a cement-on-cement antibiotic-loaded articulating spacer made with a new type of mold and evaluate the clinical results.

Materials and Methods: A retrospective case study was conducted of eight patients, mean age 71 years (range 62 to 84), who between 2011 and 2016 had been diagnosed with chronically infected TKA and who had undergone a two-stage exchange revision TKA using a cement-on-cement antibiotic-loaded articulating spacer. The mean time between the first and second stage operations was 4.5 months (range 3 to 7 months). The mean follow-up time was 26.75 months (range 12 to 40 months).

Results: No recurrence of infection was found in any of the patients. All functional outcomes improved compared to the preoperative period: Knee Society Score rose from 30 to 86, functional score increased from 16 to 81, and knee flexion increased from 68.2° to 104.7°. No spacer-related
complications were seen in any of the patients.

Conclusion: Preliminary results, based on a small sample of eight patients, indicate that the technique of intraoperatively using a cement-on-cement antibiotic-loaded articulating spacer for treatment of chronically infected TKA provides good results in eradication of infection, improvement of functional outcome, and absence of spacer-related complications.

Keywords: Infected total knee arthroplasty, Cement spacer, Antibiotic-loaded articulating spacer, Chronic infection, Two-
stage exchange, Revision total knee arthroplasty