title: [Two-stage revision for prostheses infection in patients with bone tumor after knee prosthetic replacement].
abstract: OBJECTIVE
  To evaluate the outcome of two-stage revision for prostheses infection in patients with bone tumor after knee prosthetic replacement.
  
  
  METHODS
  Between August 2003 and August 2010, 22 patients with prostheses infection, who underwent knee prosthetic replacement in limb salvage treatment because of bone tumor, received two-stage revision. There were 11 males and 11 females with an average age of 29.6 years (range, 15-55 years). Prosthetic infection occurred after primary replacement in 20 patients and after revision surgery in 2 patients from 15 days to 89 months after operation. According to Coventry and Fitzgerald classification, type I was found in 3 cases, type II in 15 cases, and type III in 4 cases. The time from infection to admission was 5-47 months (mean, 10.2 months). The results of bacterial culture were positive in 9 cases and negative in 13 cases. Two patients had fever and leukocytosis. In one-stage, the implants and infected tissue were removed, and an antibiotic cement spacer with an intramedullary nail was implanted. In two-stage, a new endoprosthesis was inserted after infection was controlled.
  
  
  RESULTS
  The C-reactive protein and erythrocyte sedimentation rate before one-stage debridement were significantly higher than those before two-stage revision (P < 0.05). All patients were followed up 5-63 months (mean, 23.6 months). Infection was controlled after one-stage debridement in 18 cases (81.8%); two-stage revision was performed in 17 cases, and 1 case refused to receive two-stage revision. Of 17 patients, 1 patient was amputated because of infection at 5 months after revision. Four patients (18.2%) underwent amputation because of failure to control infection after one-stage debridement. The limb salvage rate was 77.3% (17/22). One case of renal cell carcinoma with bone metastasis died of original disease after 1 year and 6 months of operation. The Musculoskeletal Tumor Society (MSTS 93) score was 69.4 +/- 12.7 at last follow-up.
  
  
  CONCLUSIONS
  Two-stage revision should be performed in time and it has good results in the treatment of prostheses infection in patients with bone sarcomas after knee prosthetic replacement.
authors.affiliation: Musculoskeletal Tumor Center, People's Hospital, Peking University, Beijing, 100044, P R China.
authors.forename: Tao
authors.initials: T
authors.lastname: Ji
authors.forename: Wei
authors.initials: W
authors.lastname: Guo
authors.forename: Rongli
authors.initials: R
authors.lastname: Yang
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Tang
mesh_terms: D000293:Adolescent; D000328:Adult; D001859:Bone Neoplasms / Q000601:surgery*; D005260:Female; D006801:Humans; D007719:Knee Joint; D007720:Knee Prosthesis / Q000382:microbiology*; D008297:Male; D008875:Middle Aged; D016459:Prosthesis-Related Infections / Q000601:surgery*; D012086:Reoperation / Q000379:methods*; D012189:Retrospective Studies; D055815:Young Adult