I am reprinting this article here in its entirety because it is emblematic of a serious problem. How well meaning and naive people are being given very poor and misleading information packaged as knee replacement advice by a combination of lousy journalism and research summation. Science daily purports to be “Your source for the latest research news”. I guess they are not claiming to have accurate news so at least you can’t fault them for false advertising.
First up for scrutiny is the title..”Partial knee replacement safer than total knee replacement, study finds”.
Any surgery that is more invasive (TKR), performed on an end-stage disease process (TKR-arthritis) and performed on a much older segment of the population is bound to be have more risk involved.
When the researchers conclude that people who undergo TKR are 4 times more likely to die in the first month after surgery compared to those who have a partial knee replacement, have they controlled for the age difference?
Read on… and you can note my comments in red
Partial knee replacement safer than total knee replacement, study finds
July 7, 2014
Partial knee replacement surgery is safer than total knee replacement, according to a new study published in The Lancet.
A team of researchers from the University of Oxford, funded by Arthritis Research UK and the Royal College of Surgeons, found that:
- Although the risk of life-threatening complications from knee replacement surgery is very small, people who undergo total knee replacement are four times more likely to die in the first month after surgery compared to those who have partial knee replacement, and 15 per cent more likely to die in the first eight years.
- Patients undergoing total replacement are twice as likely to have a thrombosis, heart attack or deep infection, three times as likely to have a stroke and four times as likely to need blood transfusions, compared to those having partial replacement. In addition, after total knee replacement patients are in hospital longer and the chance of being readmitted or requiring a re-operation during the first year is higher.
- Patients who had a partial knee replacement are 40 per cent more likely to have a re-operation, known as revision surgery, during the first eight years after the replacement, than those that had a total knee replacement.
Revisions are a huge problem with partials and this is basically glossed over the entire article.
Up to half of knees that require replacement, usually because of severe osteoarthritis, can be treated with either partial or total replacements. With partial replacements, also known as unicompartmental replacements, only the damaged parts of the knee are replaced and the remaining surfaces and all the ligaments are preserved.
Because of the higher revision rate of partial knee replacement surgery, which is traditionally regarded as the most important factor to determine the choice of implant, its use in the treatment of end-stage osteoarthritis is controversial, with only about 7,000 being performed annually in the UK. Partial knee replacements are often offered to younger people who, because of their higher activity levels, have increased failure rates.
Total knee replacement is one of the most common surgical procedures, with over 76,000 performed annually in the UK. Only five per cent of patients require revision surgery over a 10-year period.
Note ONLY 5 out of 100 need to be revised.
Revision, re-operation and death were uncommon outcomes of either procedure, stressed the research team.Professor David Murray, from the Nuffield Departmental of Orthopaedics, Rheumatology and Musculoskeletal Sciences at the University of Oxford, who led the research, said: ‘For an individual patient, the decision whether to have a partial or total is based on an assessment of the relative risks and benefits. The main benefit of the partial knee is that it provides better function.
The main determinants to selecting partial or TKR are
- The condition of your knee (knee damage isolated medially)
- Having a surgeon who is excellent at performing partials
See my book for more valuable information on this topic.
‘The risks have been assessed in this study, which found that partial knees have fewer complications and deaths; however they do lead to more re-operations. Patients will however be more concerned to avoid death and major complications, such as heart attack or stroke, than re-operations.
Folks this is just plain stupid:In only a small number of cases would you even be in a position to consider one or the other and just weight the risks. The risks of death is less than 1% following a total knee replacement. And there is less than 6% chance of other serious complications. See my blog post for more info.
‘To put the risks in perspective, if 100 patients had a partial knee rather than a total knee replacement there would be one fewer death and three more re-operations in the first four years after surgery.’
If the number of partial replacements were to increase from 8 to 20 per cent, the NHS could potentially prevent 170 deaths, at the cost of 400 additional revisions.
Again, this is ridiculous… a partial is either medically indicated or not. Then if it is indicated the main issue that the patient needs to decide is whether the risks of a potential revision (40%-that is 4 out of 10 my friends) and a substantially harder conversion to a total knee replacement once you’ve had the partial outweigh the benefits of shorter rehab and less invasive surgery as a whole.
Professor Murray added: ‘Patients will be concerned about death following joint replacement. However patients who have severe arthritis are very immobile and therefore tend to be unfit. Joint replacement overall, by making patients more mobile and fit tends to save lives.’
His colleague Alex Liddle, an Arthritis Research UK clinical research fellow who ran the study, added: ‘Partial and total knee replacements are both successful treatments and a large proportion of patients with end-stage knee osteoarthritis are suitable for either.
‘Both have advantages and disadvantages, and the choice of which procedure to offer will depend on the requirements and expectations of individual patient.’
The team’s study used data from the National Joint Registry for England and Wales on the adverse outcomes of more than 100,000 matched patients who had undergone both types of knee surgery.
Medical director of Arthritis Research UK Professor Alan Silman said: ‘This is a comprehensive study that provides both patients and surgeons with valuable information about the risk and benefits of two effective types of knee replacement operations. This new knowledge will enable them to make an informed decision about which type of surgery is best for particular individuals.
No Professor Silman, all you’ve done is muddy the waters and confuse people.
‘Even in the elderly, with other health problems, knee replacement is a very safe and effective procedure. These data remind us that there are still patients, who fortunately very rarely, can develop life threatening complications following surgery and we still need to find surgical approaches that takes away these risks whilst retaining a successful outcome for patients.’
Alexander D Liddle, Andrew Judge, Hemant Pandit, David W Murray. Adverse outcomes after total and unicompartmental knee replacement in 101 330 matched patients: a study of data from the National Joint Registry for England and Wales. The Lancet, 2014; DOI: 10.1016/S0140-6736(14)60419-0
Watch what you read…Misleading headlines and content can be found everywhere. Stop by frequently to get the best knee replacement advice