With over 3.5 decades dedicated exclusively to total joint replacement, our arthroplasty unit has repeatedly identified
and reported a clear correlation between cup wear on the one hand, and pain, interface widening and osteolytic
failure on the other1. However, in view of the fact that this statement has sparked some controversy, clarification
of this correlation became imperative, particularly in view of important clinical consequences.
Materials and methods were provided by a potentially long-lasting gamma crosslinked cup. The arthroplasty follow-
up ranged from 10-33 years. Objective clinical, radiographic and pathological evaluations were backed by
computer analysis through the Department of Statistics at the University of Pretoria.
We are able to conclude that the statistical correlation between wear, on the one hand, versus pain, interface
effects and osteolysis on the other, was no coincidence but instead proved to be clearly conclusive. Of great
importance is the fact that this study allowed us to set new objective criteria for true failure as well as impending
failure, thus guiding us towards sensible decision-making in terms of revision surgery in these complex
issues. Cup wear was thus clearly identified as the overwhelming leading variable in long-term prognosis in this
type of total hip replacement.