High wear rates and extensive osteolysis in 3 types of uncemented total hip arthroplasty: a review of the PCA, the Harris Galante and the Profile/Tri-Lock Plus arthroplasties with a minimum of 12 years median follow-up in 96 hips.

BACKGROUND: High wear rates and femoral and acetabular osteolysis have been-and still are-the main problems in uncemented total hip replacement. We reviewed 96 consecutive cementless total hip replacements of 4 different designs. PATIENTS AND METHODS: 21 PCA, 25 Harris Galante Porous/Harris Galante I (stem/cup), 25 Profile pressfit/ Tri-Lock Plus (stem/cup) and 25 Profile HA-coated/Tri-Lock Plus (stem/cup) prostheses were included. The operations were performed in the period 1984-1991. Median follow-up ranged from 12-16 years. Wear and osteolysis were measured.
RESULTS: Mean linear wear rates ranged from 0.17 to 0.21 mm/year in the 4 groups, and there were no statistically significant differences between the groups (p = 0.9, ANOVA). Moderate or extensive osteolysis was found in 46 of the 96 hips included. The association between high and low wear rates (more or less than 0.20 mm/ year) and extent of osteolysis was statistically significant (p < 0.001, t-test). We found poor 12-year survival of the primary prostheses in all 4 groups (50-70%), mainly due to revisions because of wear of the polyethylene liner and/or osteolysis. The infrequently documented Profile/Tri-Lock Plus systems did not perform differently from the PCA and the HG.
INTERPRETATION: The poor long-term results with these uncemented total hip arthroplasties illustrate the necessity of regular radiographic evaluation in order to detect osteolysis and liner failure, which are both generally asymptomatic until catastrophic failure appears.