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success than the previous metal on metal total hip replacements. So successful were the early patient outcomes with Birmingham hip re-surfacing that the Press seized on the concept and it was featured both in written publications but also on television, on the Tomorrow's World programme, where it was described as the 'Everlasting Hip'. In turn, The National Institute for Clinical Excellence (NICE), recommended that such a design should be considered for all active patients under 55. Many other manufacturing companies of orthopaedic prostheses wished to copy McMinn's philosophy and developed their own similar designs. Some of these were not brought to the market with such rigorous testing as McMinn had done, leading to disastrous results. One implant , the ASR hip, was manufactured by DePuy and as a resurfacing and combined with a total hip stem, very high failure rates within 3 – 7 years started appearing in the literature in 2010. DePuy withdrew the product in a world-wide product recall. As hundreds of patients have been faced with having their ASR hip resurfacing or total hip revised, guidelines were then issued regarding the introduction of novel implants both by the Department of Health, The British Orthopaedic Association and the Medical Devices Agency.
Back in Paris, Robert Judet and colleagues in the early 1970's looked for alternative means of fixation without the cement. They used rough surfaced implants to enable bone on-growth. This is now known as cementless fixation and is the most common form of fixation of hip prostheses in North America and much of Europe. Special biological coatings have been found to enhance bone on-growth and fixation.
Quality Controls Some 10 years ago, the National Joint Registry for England and Wales was created. The Registry followed on from similar Registries in Scandinavia, particularly Sweden and Finland and Australia. The goal of such Registries is to audit the outcome of hip replacement surgery between units, and in time, individual surgeons.
Elsewhere in the United Kingdom, others tried alternative bearings to Charnley's metal on polyethylene.
Between 2003 and 2012, 500,000 patient details have been stored in this audit. The audit can help to identify implants that are not as successful as others, and in turn, it may also highlight units where surgery is less successful than in other centres.
In Norwich, McKee and Farrar, tried a different design of metal on metal. A small number of these hips have lasted for over four decades, but the majority tended to 'weld' together, causing premature failure.
More and more of this information from the NJR is available to the public as well as to the orthopaedic community.
Peter Ring, working in Surrey, re-visited the idea of a metal on metal hip with cementless fixation in the 1960's, but the long term results were not as good as John Charnley's, and once again, this concept fell out of favour.
The manufacturing companies have also been asked to participate in a scheme known as 'Beyond Compliance'. This is to introduce greater control over the introduction of new technologies, hoping to avoid the problems seen with the DePuy ASR hip. In an ideal world, any new device should match the long term clinical survivorship of tried and tested implants,
It was brought back to life in the 1990's by Mr Derek McMinn and colleagues working in Birmingham. With improved metallurgy and manufacturing techniques, rather than replacing the whole of the upper femur, a capping or 're-surfacing', metal on metal design had better EXPERT WITNESS JOURNAL
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SUMMER 2014