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Methods: Eighteen knees (18 patients) with methicillin-resistant Staphylococcus aureus weretreated between January 2001 and January 2007 with one-stage revision protocol that includeddébridement, uncemented revision of total knee components, and intraarticular infusion of 500mg vancomycin via Hickman catheter once or twice daily for 6 weeks. (Figure 1) Nointravenous antibiotics were used after the first 24 hours. Serum vancomycin levels weremonitored to maintain levels between 3 and 10 µg/mL. The mean serum vancomycin peakconcentration was 6 ± 2 µg/mL and the mean serum vancomycin trough concentration was 3 ± 1µg/mL at 2 weeks postoperative.Results: Knee synovial fluid peak and trough vancomycin levels were measured in two knees.Synovial fluid peak concentrations were 10,233 µg/mL and 20,167 µg/mL and troughconcentrations were 724 µg/mL and 543µg/mL, respectively. Minimum followup was 27months (range, 27-75 months). Mean followup was 62 months, (range, 27–96 months). At 2-year followup, mean Knee Society score was 83 ± 9. No radiographic evidence of implantmigration has occurred. One knee became reinfected with methicillin-resistant Staphylococcusaureus and was reoperated at 5 months. A necrotic bone segment was found, the knee wasdebrided and revised, and the antibiotic infusion protocol was readministered. The kneeremained free of infection at 42 months postoperatively.Conclusions: One-stage revision with uncemented components and 6 weeks intraarticularvancomycin administration safely and effectively treated MRSA-infected TKA with noapparent complications.FiguresThursday, October 7, 2010, 10:20-11:00Session A3: Bearing Mobility IssuesRoughness and Surface Polarity of Retrieved Zirconia Femoral Heads*Marcel Roy - Missouri Bone and Joint Research Foundation - St. Louis, USALeo Whiteside - Missouri Bone and Joint Research Foundation - St. Louis, USATariq Nayfeh - Johns Hopkins University College of Medicine - Baltimore, USABrian Katerberg - Signal Medical Corp - St. Louis, USA*Email: mroy@mobojo.orgIntroduction: Recent clinical studies found no apparent reduction in wear using yttriastabilizedzirconia (Y-TZP) instead of cobalt chromium alloy femoral heads bearing againstcross-linked UHMWPE. The purpose of this study was to compare the surface topography ofretrieved Y-TZP and magnesia-stabilized zirconia (Mg-PSZ) femoral heads and evaluate theinfluence of time in vivo. The increase in average roughness (Ra, Sa) of Y-TZP due to phasetransformation in vivo is well documented, while Mg-PSZ does not roughen or undergo phasetransformation in vivo. However, the effects of phase transformation on the polarity (skewness,Ssk) of the surface of retrieved ZrO 2 heads has not been reported. We hypothesized that phasefile:///E|/ISTA2010-Abstracts.htm[12/7/2011 3:15:47 PM]