Introduction:

The ASR™ Articular Surface Replacement and ASR™ XL Metal-on-Metal systems were recalled due to high revision rates at five years. A worldwide clinical follow-up of patients was initiated. This paper summarizes current findings in South Africa (SA) in comparison with those outside SA (OSA).

It is estimated that 15 % of the population is allergic to metal, most commonly to Nickel, which is a common component of the alloys in most knee and hip arthroplasties. It would therefore be expected that allergy to metal is a frequent form of implant failure – but very little is reported in the literature. With the recent concerns about metal-on-metal bearings and metal ion issues, there has been renewed interest in metal allergy – with the Australian Joint Registry 2010 reporting it as a causative factor in 7 % of Hip Resurfacing revisions.

With over 200 BHR and 571 ASR Hip Resurfacing arthroplasties in my series from 2001, I have identified only 1 patient with implant failure due to metal allergy.

In 2010 two Total Knee Arthroplasty patients presented with pain and strongly positive Melisa allergy tests – these patients were revised to Titanium coated implants resulting in a complete relief of symptoms.

This paper will analyse the problem of metal sensitivity, the investigation and management of the allergic patient who has, or requires, joint arthroplasty

Introduction

A metal ion study was undertaken in patients who had received an articular surface replacement. The design of these components is optimised in line with lubrication theory and produces low levels of wear in hip joint simulators.