Abstract
Aim: To compare the outcomes of cemented and uncemented primary total hip arthroplasty and to report the radiological features of 41 Exeter polished tapered stems which demonstrate good clinical scores at long-term review.
Methods: We set up a randomised trial, involving two surgeons, Twenty stems were modular and 21 were monoblock. The radiographic measurements, made using templates adjusted for magnification, included vertical subsidence of the stem, scoring of cement mantle thickness, analysis of the p-c and cement-bone (c-b) radiolucencies, and cement fracture in each of the Gruen zones on AP and lateral views.
Loosening was classified as possible if there was between 50 and 99 percent c-b radiolucency, probable when there was complete radiolucency, or definite when vertical subsidence was more than 5mm. The presence and type of radiological features analysed according to surgeon and whether a centraliser was utilised.
Results: There were no failures of the polished stems with 100% survival at 11 years. At the latest review, none of the polished cemented stems demonstrated definite or possible loosening. Osteolysis was found proximally in two cases and more distally in one case and each of these stems was implanted without a centraliser. Incomplete cement mantles and the presence of radiolucencies were more common around stems without centralisers, however the differences in results according to surgeon is a potential confounder and requires investigation in a larger series.
Conclusion: This study demonstrated excellent radiological results of the polished Exeter stem at mid to long-term follow-up.
The abstracts were prepared by Professor A. J. Thurston. Correspondence should be addressed to him at the Department of Surgery, Wellington School of Medicine, PO Box 7343, Wellington South, New Zealand
