title: Total knee arthroplasty in hemophilic arthropathy.
abstract: BACKGROUND
  Arthropathy of the knee frequently develops in patients with hemophilia, who may require a total knee arthroplasty at a young age. Hemophilic patients, who require regular intravenous replacement of coagulation factor, have a higher prevalence of human immunodeficiency virus (HIV) infection, which can compromise the outcome of the arthroplasty. The purpose of this study was to evaluate prosthetic survival following total knee arthroplasty and identify factors associated with failures of the arthroplasties in hemophilic patients.
  
  
  METHODS
  The results of fifty-three total knee arthroplasties performed in thirty-eight patients (twenty-nine of whom were seropositive for HIV) to treat hemophilic arthropathy between 1976 and 1998 were retrospectively reviewed. Inpatient and outpatient medical records were studied to determine the HIV status, CD4 lymphocyte count, type of prosthesis, duration of prosthetic survival, cause of failure, and cause of death. If an arthroplasty failed, the outcome of the treatment of the failed arthroplasty was also determined.
  
  
  RESULTS
  The rate of survival of the prostheses was 90% after five years. Eleven total knee arthroplasties failed. The most common cause of failure was infection (seven knees), which developed at an average of sixty months (range, three to 138 months) after the arthroplasty. There was no significant difference in the CD4 lymphocyte counts between the patients in whom infection developed and those in whom it did not. The HIV status also did not appear to be related to the development of infection. Thirteen patients died, and the most common cause of death was complications associated with acquired immunodeficiency syndrome (AIDS).
  
  
  CONCLUSIONS
  Total knee arthroplasty performed to treat hemophilic arthropathy has a high risk of failure as a result of infection. Most infections developed late and were frequently caused by Staphylococcus epidermidis, suggesting that a likely cause of failure due to infection was hematogenous spread during administration of coagulation factor. It may be difficult to salvage a prosthesis complicated by infection. However, the life expectancy of hemophilic patients is lower than that of the general population of patients treated with total knee arthroplasty, and the improvement in the quality of life after total knee arthroplasty for hemophilic arthropathy may outweigh the risk of failure.
authors.affiliation: University of California, San Francisco, San Francisco, CA 94143, USA.
authors.forename: John M
authors.initials: JM
authors.lastname: Norian
authors.forename: Michael D
authors.initials: MD
authors.lastname: Ries
authors.forename: Susan
authors.initials: S
authors.lastname: Karp
authors.forename: Julie
authors.initials: J
authors.lastname: Hambleton
mesh_terms: D000328:Adult; D000368:Aged; D019645:Arthroplasty, Replacement, Knee; D005500:Follow-Up Studies; D006467:Hemophilia A / Q000150:complications*; D006801:Humans; D007592:Joint Diseases / Q000209:etiology / Q000601:surgery; D007719:Knee Joint; D007720:Knee Prosthesis; D008875:Middle Aged; D011475:Prosthesis Failure; D012086:Reoperation; D012189:Retrospective Studies; D013997:Time Factors; D017211:Treatment Failure