How to choose a hip surgeon

If you’re having a new hip put in, would you go for one with an established track record, or a brand new one with slick marketing but no safety data in humans? And which of the 107 cups to put with which of the 139 stems? A big or small head? Metal on metal, metal on plastic or ceramic on ceramic? A total hip replacement or just a resurfacing?  Unsurprisingly, most patients let their surgeon decide for them. Get it right and a hip replacement removes crippling pain and restores mobility for 15 years or more. When it fails – as 8,641did in 2011 – it can be a disaster, requiring extensive, expensive and unpleasant revision surgery that isn’t always successful. But if you ask ten different surgeons, you might get ten different opinions. So who can you trust?

In 1997, following the failure of the Capital Hip, MD advised patients to choose a hip surgeon who used a tried and tested prosthesis and had long term audit to show he or she was good at putting it in. I also campaigned for a compulsory National Joint Registry (NJR) that published comparative data for all surgeons and the joint replacements they used, so that patients could see the evidence and surgeons and regulators could spot a failing hip quickly and avoid unnecessary harm. The registry was finally up and running in 2003, but only this year has it identified hospitals with the highest joint replacement failure rates. Any hospital could have a brilliant and a woeful surgeon whose amalgamated results are ‘average,’ and patients still don’t have access to surgeon specific data. More worrying, regulators didn’t act to stop ASR hip replacements until 2010, even though the Australian joint registry had been flagging problems since 2005. 93,000 were put in worldwide, 10,000 in the UK, with failure rates up to 50%.

Part of the problem is that the UK NJR only became mandatory in 2011. Professor Paul Gregg, who helped set up the registry, strongly lobbied for a mandatory register but the DH under Labour resisted. Voluntary and incomplete reporting has allowed surgeons to hide bad results and almost certainly delayed the NJR identifying failing ASR joints and those surgeons who should have stopped using them. At the very least, the NJR should name and shame the surgeons who have not submitted all their data for independent scrutiny.

A further problem is the freedom given to orthopaedic surgeons to choose any prosthesis. New is often not better, despite what the manufacturers claim, and even small modifications can have untoward effects. And because medical devices aren’t tested in humans prior to use, problems can only be spotted in a timely way by if the registry is complete.  Surgeons in North Tees lead by Tony Nargol were convinced ASR hips would be best for over 400 of their patients, but at least were very diligent in submitting data to the NJR. In the latest NJR report, three out of the eight statistical outliers for hip revision surgery are the University Hospital of North Tees, the University Hospital of Hartlepool and Nuffield Health Tees hospital. North Tees and Hartlepool NHS Foundation Trust has also been issued with an alert because its Patient Reported Outcome Measures after hip replacement show ‘significantly lower EQ-5D Health Gain than the average across England.’

Nargol deserves credit for blowing the whistle to manufacturers DePuy and the MHRA about problems with the ASR, and is reaping rewards now by specialising in researching and revising the failed hips he and his colleagues put in, and as a medicolegal adviser against DePuy. However, the ASR patients of North Tees are not so fortunate. In 2000, NICE advised that ‘wherever possible’, the NHS should use artificial hip joints that can show they last for 10 years or more’ (i.e. with a maximum failure rate of 1% a year). Three years of data was considered and absolute minimum,  and newer prostheses such as the ASR should only be introduced in a proper clinical trial with ethical approval and full consent from patients to show they accepted the longer term risks were unknown.

The Care Quality Commission is now considering an investigation in North Tees. It needs to discover whether a proper controlled trial of ASR hips took place, whether patients consented to the potential risks and complications as they arose, whether patients were selected appropriately, whether surgeons stopped using the ASR brands quickly enough when they identified problems and whether the Trust management tried to stop them. At present, only surgeons and their chief executive have access to an individual’s NJR data and a ‘funnel plot’ of how it compares with the rest of the UK. It’s entirely up to them whether they act on it or bury it. If you’re having any joint replacement, you should demand to see your surgeon’s funnel plot. Outliers are easy to spot outside the funnel. If he or she won’t show you, run a mile. Or hobble out.

MD