Use of static or articulating spacers for infection following total knee arthroplasty

Background: The so-called gold standard for treatment of periprosthetic joint infection following total knee arthroplasty is two-stage reimplantation. However, it is unclear whether use of static or articulating antibiotic-impregnated spacers during the interim period between these two stages is superior. The purpose of this study was to compare the outcomes of static and articulating spacers in the treatment of infection following total knee arthroplasty. Methods: A systematic review of the peer-reviewed literature indexed by MEDLINE and Embase was performed to identify studies reporting the outcomes of antibiotic spacers in the treatment of infection following total knee arthroplasty. Seven Level-III comparative studies and thirty-two Level-IV case series remained following the screening process. The data in these studies were extracted and aggregated to compare the reinfection rate, range of knee motion, functional scores, and complication rates between static and articulating spacers. Results: The two types of spacers demonstrated similar reinfection rates (7% for articulating and 12% for static, p = 0.2). However, the articulating spacers resulted in significantly greater range of knee motion after reimplantation (101° for articulating and 91° for static, p = 0.0002). Despite this difference in ultimate knee motion, functional scores in the treatment groups were similar. Rates of wound-related and spacer-related complications were similarly low with both types of spacers. Conclusions: Our review failed to identify a significant difference in the ability of static or articulating spacers to eradicate periprosthetic infection following total knee arthroplasty. Compared with static spacers, articulating spacers provided improved knee motion following reimplantation, although functional scores were similar in the two treatment groups. We encourage arthroplasty surgeons to consider both static and articulating spacers in the treatment of infection following total knee arthroplasty and to tailor treatment on the basis of patient-related factors. Level of Evidence: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.