Total hip arthroplasty in adult patients who had childhood infection of the hip.

BACKGROUND: Adult patients with a history of infection of the hip in childhood present a challenge as candidates for total hip arthroplasty because of abnormal bone development, soft-tissue contractures, the possibility of reinfection, and their relative youth. The purpose of this study was to analyze the mid-term results of primary total hip arthroplasty in adult patients who had had infection of the hip in childhood.

METHODS: We retrospectively analyzed 170 total hip arthroplasties that had been performed between 1983 and 1996 in patients who had had infection of the hip during childhood. Forty-seven hips had cemented or hybrid total hip replacements, and 123 hips had cementless total hip replacements. The age of the patients at the time that the infection was contracted was an average of 7.3 years (range, one to eleven years). The average age of the patients at the time of the index total hip arthroplasty was 41.9 years in the cemented or hybrid group and 42.7 years in the cementless group. The interval between active infection and arthroplasty was 34.9 years in the cemented or hybrid group and 31.9 years in the cementless group. All but two hips (one patient) had a quiescent period of infection of more than ten years. The average duration of follow-up was 9.8 years (range, seven to seventeen years) in the cemented or hybrid group and 10.8 years (range, seven to seventeen years) in the cementless group.

RESULTS: All hips with a quiescent period of more than ten years had no recurrence of infection. The remaining two hips in one patient with a quiescent period of seven years had recurrence of the infection. The mean Harris hip scores improved from 50 points preoperatively to 85 points at the latest follow-up examination in the cemented or hybrid group and from 50 points preoperatively to 89 points at the latest follow-up examination in the cementless group. Eight (17%) of forty-seven hips with cemented or hybrid fixation and eighteen (15%) of 123 hips with cementless fixation had revision of both components because of aseptic loosening and/or osteolysis. The mean rate of linear wear of the polyethylene was 0.25 mm per year in the cemented or hybrid group and 0.29 mm per year in the cementless group. The prevalence of osteolysis was 53% (twenty-five of forty-seven hips) in the cemented or hybrid group and 59% (seventy-two of 123 hips) in the cementless group.

CONCLUSIONS: There was no recurrence of infection after total hip arthroplasty in the patients with a quiescent period of infection of more than ten years. These young, active patients with technically difficult arthroplasties were at considerable risk for aseptic loosening. The prevalence of polyethylene wear and osteolysis was attributable to the less than optimal prosthetic designs and materials used during the time-period of this study.