Patient selection does not improve the success rate of infected TKA one stage exchange

One stage exchange of a chronically infected total knee arthroplasty (TKA) is recommended in selected cases only. However, there is little evidence regarding the usefulness of selection criteria. The goal of this retrospective study was to compare the results of two concomitant cohorts of patients with chronically infected TKA: one treated with a routine one-stage exchange (study group) and one treated with one-stage exchange in selected cases only (control group). The hypoyhesis tested was that the failure rate and repeat surgery rate were higher in the study group than in the control group.

One hundred and thirty one cases were selected: 54 in the study group and 77 in the control group. There were 63 men and 68 women with a mean age of 70 years. All patients were followed up for a minimal period of time of two years or until death or recurrence of infection.

Twenty five cases had a recurrence of infection: 9/54 in the study group and 16/77 in the control group (NS). The survival rate for being free of infection after four years was 85% in the study group and 78% in the control group (NS). The repeat surgery rate was significantly higher in the control group.

The tested hypothesis was rejected. When one stage exchange is considered, patient selection does not improve outcome.