Correlation of wear debris-induced osteolysis and revision with volumetric wear-rates of polyethylene - A survey of 8 reports in the literature

This survey focused on clinical reports of polyethytene wear and osteolysis in total hip replacements. With regard to documentation of clinical wear-rates, 57 publications were reduced to an analysis of 8 reports of THR series, including the incidence of osteolysis, A direct correlation mas found among volumetric wear-rates, incidence of osteolysis and revision rates in THR concepts of the 1983-1987 era. As volumetric wear rate increased, the incidence of osteolysis and revision rates increased With regard to our grading system for volumetric wear, with follow-up in the 4-15 year range, osteolysis was rare in group A (wear = 0-80 mm(3)/year), ranging from 6% to 31% in group B (wear 40-80 mm(3)/year) and from 21% to 100% in group C (mear > 140 mm(3)/1year). With regard to cup design, the optimal low-wear group had mainly cemented polyethylene cups with 22 and 28 mm head sizes, The mid-wear group B had metal-backed cemented and uncemented cups, with 28 mm head size, and the high-risk group C had only uncemented, metal-backed cups, with the highest mear in the 32 mm head size. Less than 10 years of follow-up did not distinguish adequately between different designs of THR, except in a fem cases which had early failures due to material or design deficiencies. Overall, the cemented all-polyethylene cup combined with the smaller ball head proved to be better.