A facile technique to make articulating spacers for infected total knee arthroplasty.

BACKGROUND: To treat total knee arthroplasty, 2-stage revision, including removal and reimplantation, remains the standard treatment for the infected arthroplasty. Articulating cement spacer has been shown to provide better functional results after reimplantation. However, its cost as a manufactured product is not always easily affordable and the choice of antibiotics is not flexible either. The authors have developed a method for surgeons to make cement-on-cement articulating spacers themselves by using an impression-taking technique with polydimethyl siloxane. The current study was conducted to test their clinical efficacy.

METHODS: Fifteen patients with infected total knee arthroplasties were prospectively treated with 2-stage revision using articulating spacers made by this technique. The clinical assessment included intraoperative finding, surgical records, radiographic and laboratory examination and final functional scores. All the patients were regularly followed-up.

RESULTS: Fourteen of the 15 patients (93.3%) had infection eradicated, of which 13 patients received revision arthroplasty successfully. The average interval between the resection arthroplasty and the final procedure was 3.5 months. During this period, most of the patients could sit comfortably with bent knees and walk with partial weight-bearing. No patients had secondary bone loss. The range of motion after revision surgery achieved an average of 110 degrees. The average Hospital for Special Surgery score was 90.5 points, and none had recurrent infection after an average of 47.5 months of follow-up.

CONCLUSION: Treating infected total knee arthroplasty with these self-made articulating spacers eradicates infection effectively, improves the life quality before reimplantation and provides good final results without significant complications.