Cementless uncoated polyethylene acetabular components in total hip replacement. Review of five- to 10-year results

Abstract

We reviewed the results of 545 consecutive total hip replacements using a cementless non-coated high-density polyethylene acetabular component combined with a cemented Muller stem at five to 10 years. In all, 421 patients (445 hips) were available for review, 118 by questionnaire and 303 by examination and radiography. Of these, 86% had a good or excellent result. We found a high rate of radiological loosening of the cup after the sixth year, and a high rate of clinical loosening after the eighth year. Loosening was commoner in women, in younger patients and where a smaller size of acetabulum had been used. Calcar resorption was significantly related to loosening of the acetabulum. Loosening appeared to be mainly due to polyethylene debris produced by micro-movement of the acetabulum against the bone, which had resulted in a giant cell foreign body reaction and subsequent bone erosion. We have abandoned the use of this prosthesis and suggest that direct contact between bone and polyethylene should be prevented by a coating of metal or some other material.

Cementless total hip arthroplasty with a threaded acetabular cup

“…Other studies have shown that sex was a factor influencing the results of threaded smooth cups [3,22], but we did ot find any differences in clinical and radiological results. Four of the 5 patients revised were women, and there are 2 women in the 6 patients awaiting revision.…”

More failures of uncemented acetabular screw-rings than of cemented polyethylene cups in total hip arthroplasties

“…Many authors have reported results of the Muenchen screw-ring that do not show a higher loosening rate [1,8,9,12,16,17]; however, on the basis of our results we think this component should not be used in primary total hip arthroplasty.…”

Towards the optimal design of an uncemented acetabular component using genetic algorithms

“…The results indicated that the volumetric wear rate of the UHMWPE acetabular component was considerably greater (15-800 times) than for the other materials. Owing to high wear generation, cementless polyethylene acetabular components are not recommended by clinicians (MacDonald, Morscher, and Masar 1990;Grigoris, Roberts, and McMinn 1993).…”