The Fate of Spacers in the Treatment of Periprosthetic Joint Infection.

BACKGROUND Two-stage exchange arthroplasty remains the preferred method to treat periprosthetic joint infection. The aim of this study was to investigate the clinical course of periprosthetic joint infection following resection arthroplasty and insertion of a spacer. METHODS Our institutional database was used to identify 504 cases of periprosthetic joint infection (326 knees and 178 hips) treated with resection arthroplasty and spacer insertion as part of a two-stage exchange arthroplasty. A review of the patient charts was performed to extract information relevant to the objectives of this study that included the details of the clinical course following resection arthroplasty. RESULTS The mean follow-up duration after initial spacer implantation was 56.2 months. Reimplantation occurred in the joints of 417 (82.7%) of 504 cases. Of these 417 cases, 329 (78.9%) had a minimum one-year follow-up, and 81.4% of these had successful treatment. The mean duration from resection arthroplasty to reimplantation was 4.2 months (range, 0.7 to 131.7 months). Sixty (11.9%) of the 504 joints required interim spacer exchange(s). Of the eighty-seven cases that did not undergo reimplantation, six (6.9%) required amputation, five (5.7%) underwent a Girdlestone procedure, four (4.6%) underwent arthrodesis, and seventy-two (82.8%) underwent spacer retention. Thirty-six patients died in the interstage period. CONCLUSIONS The commonly held belief that two-stage exchange arthroplasty carries a high success rate for the eradication of periprosthetic joint infection may need to be reexamined. A considerable number of patients undergoing the first stage of a two-stage procedure do not undergo a subsequent reimplantation for a variety of reasons or require an additional spacer exchange in the interim. Reports on the success of two-stage exchange should account for the mortality of these patients and for patients who never undergo reimplantation.