Two-stage exchange arthroplasty using a functional antibiotic-loaded spacer in the treatment of the infected knee replacement: the Vancouver experience.

Two-stage exchange arthroplasty is currently the method of choice in the treatment of the infected knee replacement. The prosthesis of antibiotic-loaded acrylic cement (PROSTALAC) is a temporary, antibiotic-loaded functional prosthesis that is used as an interim spacer in two-stage exchange arthroplasty. In this prospective series, we report on the early results of the use of the PROSTALAC knee spacer in two-stage exchange arthroplasty of infected knees. A total of 24 knees were treated with this prosthesis, and were reviewed at a mean follow-up time of 2.2 years. Infection was controlled in all but 2 knees, for an infection cure rate of 91.7%. The patients' function was improved between stages, and motion was maintained in the majority of cases. The significant complications with the PROSTALAC implant in place were tibio-femoral instability, which was corrected with a design modification, and patellar instability, which continues to be a problem. These complications were transient and were not of any significance after the second stage.