Articulating Versus Static Antibiotic Loaded Spacers for the Treatment of Prosthetic Knee Infection

Study Summary

Infection remains a difficult-to-treat complication of total knee arthroplasty. The gold standard treatment is two-stage removal of the prosthesis with later replacement of permanent implants. The first stage consists of removal of the infected arthroplasty components and the surrounding devitalized tissue, copious pulsed irrigation, and placement of a temporary antibiotic-impregnated cement spacer. This spacer typically is left in place six weeks, during which time the patient receives intravenous antibiotics. After the surgeon feels that the infection has been eradicated, or if the patient requires repeat debridement, a second operative procedure is performed. While the use of an antibiotic-loaded spacer is well accepted, whether the spacer should immobilize the knee (a so-called "static" spacer) or allow for range of motion (a so-called "articulating" spacer) is controversial. Proponents of articulating spacers argue that they prevent scarring of the musculature surrounding the knee resulting in easier reimplantation, improved long-term knee function, and improved range of motion. Proponents of static spacers argue that immobilization of the periarticular soft tissues aids in clearance of the infection and is simpler to fashion intraoperatively. While good results have been described with both methods, comparative trials have been conflicting as to whether spacer design alters knee function, operative time, and range of motion. Equipoise exists within the literature, and no randomized clinical trial has been conducted to evaluate this issue. The purpose of this study is to compare articulating and static antibiotic-impregnated spacers for the treatment of chronic periprosthetic infection complicating total knee arthroplasty through a prospective, randomized clinical trial. The goals of this trial are to determine the effect of spacer design upon eradication of infection, knee function, ease of reimplantation, and range of motion. The investigators hypothesize th

Interventions

• PROCEDURE Static Spacer
• PROCEDURE Articulating Spacer