title: Success rates for initial eradication of peri-prosthetic knee infection treated with a two-stage procedure.
abstract: BACKGROUND
  In Germany, rates of primary total knee arthroplasty procedures and exchange arthroplasty procedures continue to rise. Late-onset peri-prosthetic infection constitutes a serious complication whose management may be dependent upon the spectrum of micro-organisms involved. The aim of this study was to provide a retrospective analysis of the effectiveness of initial eradication measures performed as part of a two-stage procedure.
  
  
  METHODS
  Between 2002 and 2008, a total of 328 patients who had received a first-time diagnosis of chronic peri-prosthetic knee infection following total knee arthroplasty (TKA) subsequently underwent surgery at our clinic. The surgical approach consisted of a two-stage procedure, with the initial procedure consisting of the removal of the prosthesis and radical debridement, followed by insertion of an antibiotic-loaded static spacer. The effectiveness of the procedure was assessed after six weeks, with each patient undergoing a number of clinical and laboratory-based tests, including knee joint aspiration.
  
  
  RESULTS
  Staphylococcus aureus strains were responsible for 68% (n=223) of the total number of cases of peri-prosthetic knee infection. 19% of cases (n=62) showed evidence of gram-negative bacteria, while MRSA accounted for 15% (n=49) of cases. Six weeks after completion of the above-named treatment regimen, eradication of infection was considered successful in 289 patients (88.1%). Eradication was unsuccessful in 22% of MRSA infections (n=11) and 7% of MSSA infections (n=23).
  
  
  CONCLUSIONS
  The treatment regimen outlined in this report is capable of achieving satisfactory results in the management of late-onset peri-prosthetic knee infection, with one exception: patients with infections caused by MRSA showed high failure rates.
authors.affiliation: Department of General and Trauma Surgery, BG-Universitaetsklinikum 'Bergmannsheil' Ruhr-Universitaet Bochum, Germany.
authors.forename: Andrzej
authors.initials: A
authors.lastname: Kaminski
authors.affiliation: Department of General and Trauma Surgery, BG-Universitaetsklinikum 'Bergmannsheil' Ruhr-Universitaet Bochum, Germany.
authors.forename: Mustafa
authors.initials: M
authors.lastname: Citak
authors.affiliation: Department of General and Trauma Surgery, BG-Universitaetsklinikum 'Bergmannsheil' Ruhr-Universitaet Bochum, Germany.
authors.forename: Thomas Armin
authors.initials: TA
authors.lastname: Schildhauer
authors.affiliation: Nordwest-Krankenhaus Sanderbusch GmbH, Department of Orthopaedic Surgery, Sande, Germany.
authors.forename: Tobias
authors.initials: T
authors.lastname: Fehmer
mesh_terms: D000328:Adult; D000900:Anti-Bacterial Agents / Q000008:administration & dosage*; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects* / Q000379:methods; D001424:Bacterial Infections / Q000188:drug therapy*; D001843:Bone Cements; D024901:Drug Resistance, Multiple, Bacterial; D005260:Female; D005858:Germany; D006801:Humans; D007720:Knee Prosthesis / Q000009:adverse effects / Q000382:microbiology; D008297:Male; D008875:Middle Aged; D016459:Prosthesis-Related Infections / Q000517:prevention & control* / Q000601:surgery; D012189:Retrospective Studies
chemical_list: D000900:Anti-Bacterial Agents; D001843:Bone Cements