Background: The outcome of total knee replacement in patients with
hemophilia has been variable. Several authors have suggested a relationship
between high rates of late infection following total knee replacement in
patients with hemophilia and a positive HIV status. The objective of this
study was to evaluate the results of primary total knee replacements performed
in a large group of hemophilic patients at a single institution by the same
primary surgeon.
Methods: The results of ninety primary total knee replacements
performed in sixty-eight hemophilic patients between 1975 and 2001 were
reviewed retrospectively. The HIV status and the CD4 count at the time of the
surgery were recorded for fifty-three patients (seventy-one knees). Knee
Society clinical and functional scores were determined for twenty-nine
patients (thirty-eight knees) who were available for follow-up. Prosthetic
survival was calculated with use of Kaplan-Meier survivorship analysis.
Results: The overall prevalence of infection was 16%. Twelve knees
required removal of components, and the reason for the removal was late
infection in nine of them. The prevalence of infection in HIV-positive and
HIV-negative patients was 17% and 13%, respectively (p = 0.5). When component
removal for any reason, survival free of infection at any point, and
mechanical failure were considered to be the end points, the ten-year survival
rates were 83%, 77%, and 96%, respectively. The Knee Society clinical score
was excellent or good for 80% of the knees, and the Knee Society functional
score was excellent or good for 97% of the knees.
Conclusions: Despite the anatomical challenges, the mechanical
survival of total knee replacements in patients with hemophilia is quite good.
However, the prevalence of infection after the total knee replacements was
high. The prevention of late infection would substantially improve the
long-term outcome of total knee replacements in this patient population.
Level of Evidence: Therapeutic study, Level IV. See
Instructions to Authors for a complete description of levels of evidence.