best UK knee replacements

The best – and the worst – knee replacements have been revealed

Due to an ageing yet active population and a leap in technology, more and more people are being given knee replacements. Patients are understandably more concerned with the skill and experience of their surgeon, but there is also a range of different prosthetic implants that can be used. Now, a large-scale UK study has been carried out in the performance of different prosthetic implant combinations.

Unsurprisingly, what with the range of products, some knee replacements work better than others – and the recent study conducted by researchers at the University of Bristol has looked into the quality and performance of the most commonly used replacements, concluding that certain brands of joint replacement have more than double the benchmark level of failure after ten years, while others are three times more likely to need replacing than their better counterparts.

However, the good news is that the vast majority of knee implants used by the NHS – 89% of them – are deemed to perform better than standard.

The research team compared different brands and models of implants, which were implanted into over 1.7 million British patients between April 2003 and December 2016 and tracked whether follow-up surgery was needed after the procedure. In particular, they were looking for the types of implant that exceeded a failure rate of 5% – the benchmark level set by both the NHS watchdog the National Institutes for Health and Care Excellence (NICE) ODEP – the Orthopaedic Data Evaluation Panel.

The joint last implants

After scouring the data, they found seven models which failed to make the cut – with the worst performer being the Preservation Unicondylar fixed knee replacement, which was used in 398 operations and had a failure rate of 15 per cent. The list in full:

  • Preservation Unicondylar (15%)
  • Oxford Partial Knee Unicondylar (11.54%)
  • MG Uni Unicondylar (10.03%)
  • AGC Uncemented (7.76%)
  • NexGen Cement (7.13%)
  • Rotaglide + Cement (5.61%)
  • Profix Cement (5.03%)

While the research revealed that knee replacements were more prone to failure than their hip counterparts, it also revealed that the majority of knee replacements used in the UK were far more durable.; 51 were below the 5% threshold, and 16 of them had failure rates lower than half the benchmark.

As a patient – or potential patient – what can you do to ensure you get the best shot of a long-lasting and successful knee replacement? After all, it’s not as if you can run your finger down a shelf and pick out the one you like. Your best defence – as with all surgical procedures – is to be fully prepped. Ask your knee surgeon which implant is being used, and definitely ask about its success rate.

female ACL injury

Contraceptive pill could help protect women from ACL knee injuries

Everyone in the sports medicine community is aware that, due to a combination of hormonal and physiological reasons, women are far more prone to female ACL injury, but the truth is far more jaw-dropping:  women are actually eight to ten times more likely to suffer from an ACL injury than men. The knock-on effects are ruinous: recent studies have concluded that nearly half of women sports participants are forced to abandon their athletic careers, and between 20 and 50% of female athletes go on to develop arthritis within ten to twenty years.

So, it goes without saying that the race is on to bridge the gap between the sexes when it comes to an ACL injury, and the latest development comes right out of the left field: the potential benefits of the contraceptive pill.

Could the Pill cure your ACL ills?

According to a study recently published in America’s Physician and Sportsmedicine journal, female athletes are being advised to go on the pill to avoid career-ending injuries – with the apparent protective effect of the drug particularly potent in teenage sportswomen.

The study, conducted by a research team from Brown University in Rhode Island, compared rates of injury among 82,874 sportswomen taking oral contraceptives during the 12 months prior to the injury, and compared it with the same number of women not on the pill. According to the findings, a total of 465 women in the oral contraceptive group required surgical reconstruction of the ACL over the ten-year period of the study, compared to 569 in the control group. Which means that out of the entire study group, the women who were using oral contraceptive were 18% less likely to damage their ACL.

More surprisingly, when the data on female athletes aged 15 to 19 were analysed, the conclusion was that a whopping 63% of women in that group using the pill were less likely to suffer an ACL injury.

So, what’s the reason for this?

The research team at Brown believe that the lower and more stable hormonal levels that are brought on by the pill help to keep the ligaments firmer. “Young athletes use oral contraceptives for a variety of reasons, including regulating their menstrual cycle and/or preventing pregnancy,” said Dr Steven DeFroda, leader of Brown’s research team. “It’s likely that oral contraceptives help maintain lower and more consistent levels of oestrogen and progesterone, which may lead to a periodic increase in laxity and subsequent risk of tear.”

Of course, it needs pointing out that this is an observational study, so no firm conclusions can be drawn about cause and effect – and the authors point to several limitations, such as not assessing participation in particular sports or their activity level which may explain why some women tore their ACLs and others did not.

They also note that the study did not distinguish between athletic, recreational, or accidental ACL injuries, and only looked at women with injuries that were managed with surgery. So, while it’s an interesting potential solution to the rampant levels of ACL injuries in women, a study which tracks athletes over time to see whether those who take oral contraceptives have fewer ACL injuries than others will be needed.

infection after knee replacement

Infection after knee replacement: new research could help identify those most susceptible

Knee replacement surgery has become a common procedure, with over 110,000 of them carried out per year in the UK, and for the vast majority of people, it’s a pretty straightforward operation with nothing but benefits when the recovery period is over. However, the biggest problem for surgeons (and especially patients) is the risk of infection in the treated area, which could lead to serious complications down the line. It must be stressed that the risk is extremely minor, but at present 1% of patients run the risk of deep infection in the knee area, which can have some pretty nasty knock-on effects.

However, new research funded by the National Institute for Health Research (NIHR) has taken steps to identify which groups of people are most likely to develop a severe infection after knee replacement surgery and therefore need the joint replacement redone.

Zoning in on the risk factors

The study – the largest of its kind – was conducted by researchers from the Musculoskeletal Research Unit at the University of Bristol, who combed the records of the 679, 010 people who had undergone knee replacement surgery in England and Wales between 2003 and 2013 and tracked their progress in the year after their procedures, zoning in on the data of those who had suffered a knee infection.

According to their findings, the groups of people most at risk from needing their joint replacement redone due to infection include patients under 60 years of age; males; those with chronic pulmonary disease, diabetes, or liver disease; and people with a higher body mass index.

The research team didn’t stop there: they also deduced that the reason for surgery, the type of procedure performed and the type of prosthesis and its fixation also influenced the risk of needing revision surgery for an infection.

A clearer picture for practitioners

The goal of this research is to arm practitioners with a honed and refined set of guidelines, in order to help them zone in on the patients who will be most at-risk and prepare themselves to nip any future complications in the bud – be they early on in the post-surgery period, or years later.

It goes without saying that these findings could be a boon for the knee surgery community and future patients alike. Knee replacement surgery is a costly and time-consuming procedure, but having to re-do it is even costlier. And with the number of procedures rising year-on-year due to an ageing population, every re-done procedure means a longer wait for those desperate for their own knee procedure. By identifying possible raised risk factors for infection after knee replacement surgery will help practitioners to develop strategies to minimise the risk.

Call 0203 195 2443 to arrange a consultation with Mr Jonathan Webb and he will discuss all potential risks and complications including infection after knee replacement surgery before you make the decision to go ahead.

weight loss before knee replacement surgery

New study finds ideal weight loss target for obese patients before knee surgery

If you’ve been classed as morbidly obese (which according to the NHS is a BMI of over 40) and you’re awaiting knee replacement surgery, you’ve already been told that losing weight is a must. Makes perfect sense: after surgery, your knee will be temporarily weaker until it completely mends, and the more weight you can keep off it, the better.

The question is; how much weight should you be aiming to lose to maximise your chances of a short recovery period? Many medical experts advise patients to lose between five and ten pounds before going under the knife, but a new study claims that for the full benefit, you should be aiming at dropping 20 pounds beforehand.

The study, conducted by a research team from the Geisel School of Medicine at Dartmouth College in New Hampshire, involved data harvested from 203 patients who were either 100 pounds over their ideal body weight, had a BMI of over 40, or had a BMI of 35 and also suffered from high blood pressure or diabetes prior to their total knee arthroplasty procedure.

Well worth the (loss of) weight

The team tracked the study group’s weight loss regime in the three-month run-up to their surgery and discovered that in the three months leading up to their TKA procedure, 41% of the patients lost at least five pounds, 29% lost at least 10 pounds and 14% lost at least 20 pounds. After the surgery, 27 patients were no longer morbidly obese, although 23 of those were still severely obese (with a BMI between 35 and 40).

The research team presented their findings t the annual meeting of the American Academy of Orthopaedic Surgeons last month, and reported that – when compared to patients who did not lose 20 pounds – the patients who did had a 72% possibility of being discharged to a rehab facility and 76% lower odds of staying in the hospital for at least four days.

Ten pounds isn’t enough

While there were no differences in operative time or physical function improvement for the two groups, the researchers noted that losing five or ten pounds did not make a difference for any outcome.

“Twenty pounds is the magic number, based on our evidence,” claimed study leader Dr Benjamin Keeney. “This is even after accounting for age, gender, and other diagnoses besides obesity, as well as baseline physical and mental function.” He pointed out that the people who lost twenty pounds and reaped the benefit of an improved outcome were still very obese at the time of surgery – and that most of them even gained a lot of that weight back afterwards – but even so, the temporary loss of weight still led to a better outcome.

“What this study is telling us is that morbidly obese patients who lose at least twenty pounds before knee replacement are going to come home from the hospital faster and are much less likely to go on to be discharged to a facility,” he claimed. “This is a concrete goal, instead of telling patients we won’t operate unless they get a BMI of 40 – which for some patients can be a loss of 50 to 100 pounds.”

For more advice on how best to prepare for knee replacement surgery, call 0203 195 2443 to arrange a consultation at Mr Jonthan Webb’s London orthopaedic clinic.

ACL Reconstruction Surgery London

New therapy could slow down bone loss after ACL reconstruction surgery

An Anterior Cruciate Ligament reconstruction is a very effective procedure that can put right years of punishment on the knee, but there’s a downside – people who have undergone ACL reconstruction often face bone and muscle loss immediately following the procedure, due to enforced inactivity and other factors.

However, research from the Houston Methodist Hospital which was published last month points towards a solution: a combination of blood flow restriction (BFR) therapy and traditional rehabilitation efforts, geared towards slowing bone loss and reducing return-to-function time.

The study involved 23 active and young patients (with an average age of 23) who had undergone ACL reconstruction, who were put into two groups. While both groups received the same rehab protocol, one group received BFR therapy: namely, they exercised with an 80% arterial limb occlusion using an automated tourniquet.

What is blood flow restriction therapy?

BFR therapy does pretty much what it says on the tin: a surgical tourniquet system which resembles a blood pressure cuff is applied to an injured arm or leg, which temporarily reduces blood flow to the limb while the patient exercises. The reason for this is to allow the patient to work the muscles without the risk of putting excessive weight on the limb in question while activating the muscles on that limb. It’s a relatively new method – one which has its supporters and detractors.

After both groups were measured for bone mineral density, bone mass, and lean muscle mass, the research team concluded that the addition of BFR therapy to standard rehab exercises was found to prevent muscle mass loss in the whole leg and thigh in the post-operative limb compared to rehab alone. Not only that, but the addition of BFR also appeared to minimise losses in bone mineral content and preserve bone density in the limb compared to standard rehab alone.

Tied to be fit

“Providing BFR as part of the rehabilitation efforts following ACL surgery appears to help preserve the bone, recover muscle loss and improve function quicker, according to our research,” said Bradley Lambert, the lead researcher. “BFR is a suitable additive therapy to ACL rehabilitation for the purposes of minimizing the loss, and enhancing the recovery of muscle, bone, and physical function.

“While further research is needed to fully illuminate the physiologic mechanisms responsible for our results, these findings likely have wide-ranging implications for fields outside of ACL rehab alone such as injury prevention, age-related muscle and bone loss, military rehabilitation, and potentially space flight,” said Lambert.

We have known about the effects of blood flow restriction as a means of improving muscle recovery for a while now – particularly in situations where the joint cannot be loaded heavily as it heals. But the idea that the technique can make an improvement in the bone mineral density recovery is a new revelation and definitely worth looking into further.

The downside of BFR is that it’s heavily reliant on outside help and is only usually available in a professional setting – but if you’re in rehab and the technique is available to you, it’s definitely worth taking up with your support system.

knee arthritis surgery London

How exercise can help with knee arthritis

The last thing you might feel like doing in the aftermath of a knee OA procedure is to kickstart a workout programme, but two separate studies released last month pointed out that you should only sit on the sofa with your leg up for so long.

The first study – from Queen Mary University in London and published in the journal Osteoarthritis and Cartilage – has demonstrated that mechanical forces experienced by cells in joints during exercise prevent cartilage degradation, by suppressing the action of inflammatory molecules which cause osteoarthritis.

Squash the pain away

 

As the study points out, exercise – even the simple stuff, such as a brisk walk – ‘squashes’ the cartilage in joints such as the hip and knee. And this mechanical distortion is detected by the living cells in the cartilage, which then blocks the action of inflammatory molecules associated with conditions such as arthritis.

The researchers are hoping that these findings will help in the search for treatments for arthritis, which affects over three million people in the UK. And the researchers are even suggesting that the results may lead to a whole new therapeutic approach known as mechano-medicine, in which drugs simulate the effect of mechanical forces to prevent the damaging effects of inflammation and treat conditions such as arthritis.

Future complications? Walk them off

But what about the risks of agitating a post-op knee with exercise? Well, the other study – compiled by Northwestern University in Chicago – claims that there is no direct link between knee pain and daily walking, or other forms of low-intensity exercise. Furthermore, people with knee OA who undertook less than ten minutes of brisk walking per day are boosting their chances of preventing disability in later life.

The study, which was published in the American Journal of Preventative Medicine, involved 1,500 people between the ages of 49 and 83 from the rolls of America’s Osteoarthritis Initiative, who were given accelerometers and tracked between 2008 and 2014. And according to their findings, the research team found that those who managed less than ten minutes of moderate-to-vigorous activity per day found it easier to perform daily tasks than those who lived a more sedentary lifestyle.

When the exercise levels were raised a notch, the findings were even more positive: participants who managed an hour of moderate-to-vigorous activity per day had an 85% reduced risk of mobility disability – which was defined by the researchers as being unable to safely cross the street in time – and a 45% reduction of daily living disability, which is defined as having difficulty in bathing and dressing without help.

Speaking as someone affected by knee arthritis, I can vouch for the benefits of exercise as a coping mechanism, as it has definitely helped my knee. After a year of strength training, I’ve got to the point where I have been able to run 4K – with minimal aftereffects, I might add. Given that I was on the point of undergoing knee replacement prior to this, I feel the results are pretty impressive – and if you’re in the same boat as me, I’d advise you to embrace an exercise regime under the guidance of your doctor or knee specialist.

diet and knee osteoarthritis

Could a low carb diet relieve the pain of knee osteoarthritis?

We know all about the pros and cons of a low-carb diet: on the plus side, it’s the best way to kickstart fast weight loss – and weight loss in the best places, such as the abdomen. It also increases the levels of HDL cholesterol (the ‘good’ cholesterol), whilst decreasing blood sugar and insulin levels, and may even help lower blood pressure.

But according to a new report from the University of Alabama, which has been published in the Pain Medicine journal, there may be another incentive to dump the carbs, particularly if you have knee problems: a randomised controlled study they conducted recently points to the possibility that a low-carb diet could relieve pain for people who have knee osteoarthritis, particularly if you’re up there in years.

While there are medical and procedural ways to deal with knee OA, they’re costly to health bodies and can bring on side-effects for the patient – which means that the global medical community is now focusing attention on the beneficial links between a low carb diet and knee osteoarthritis symptoms.

Three diets, one outcome

The study, led by Dr Robert Sorge, Director of the PAIN Collective in the University of Alabama at Birmingham Department of Psychology, involved 21 adults aged between 65 and 75 who suffered from knee OA. One group of seven were put on a low-carb diet; the others were split into a group which took part in a low-fat diet regime, while the remaining seven continued their regular diet.

Every three weeks into the 12-week study, the research team analysed the participants’ functional pain — the pain they endured while undertaking daily tasks — as well as their self-reported pain, quality of life, and level of depression. They also took blood samples and examined them for oxidative stress – the chemical imbalance between the production of free radicals and the body’s antioxidant properties, which is seen as a useful marker of biological ageing.

Less carbs, less pain?

The results? According to the research team, the group in the low-carb group reported a reduction in functional pain levels and levels of self-reported pain, when compared to the groups on the low-fat and regular diets. Not only that, but the participants in the low-carb diet also showed less oxidative stress and lower levels of leptin, a hormone with important metabolic functions.

“Our work shows that people can reduce their pain with a change in diet,” said Dr Sorge. “Many medications for pain cause a host of side effects that may require other drugs to reduce. The beneficial side effects of our diet may be things such as reduced risk for heart disease, diabetes and weight loss — something many drugs cannot claim.”

While it’s clear that further study is required – preferably with a much bigger sample group – I think this could be very interesting. An amazing physiotherapist I work with is on a crusade to promote low carb dieting in the recovery phase. I’m starting to wonder if cutting out the carbs and switching to low carbs such as lean meats, fish, eggs, leafy greens, cauliflower, broccoli, nuts, seeds, nut butter, coconut oil, olive oil, and dairy products (and even tofu and tempeh) – is the way forward, both to recommend to my patients but also to adopt myself and combat my own knee osteoarthritis.

ACL reconstruction in female athletes

Higher rate of knee injuries found in female athletes after ACL reconstruction

We’ve already discussed data emanating from the USA about the higher rate of ACL injuries amongst female athletes when compared to their male counterparts – and a new study from over the Atlantic not only confirms that, but also reveals even more alarming information.

According to the study, which was recently published in the American Journal of Sports Medicine, a higher rate of new ACL injuries and other new knee injuries occurred among female soccer players who underwent ACL reconstruction when compared with data culled from their female knee-healthy counterparts.

In their study, the research team matched 117 active female football players who had undergone ACL reconstruction with 119 knee-healthy female soccer players from the same teams and tracked their progress over two years, encouraging the participants to answer a web-based questionnaire that addressed their participation in soccer, and logged new acute-onset or non-traumatic injuries to either knee, or injury to other body locations. They also graded the participants’ current activity level according to the Tegner Activity Scale – both at baseline and at the end of the two-year follow-up.

A traumatic result for ACL victims

The results showed an almost fivefold higher incidence of new ACL injuries, and a seven-times higher incidence of knee injury treated with surgery among players who underwent ACL reconstruction, compared to their healthier counterparts. During the two-year follow-up, the research team discovered that 62% of players who underwent ACL reconstruction gave up the sport, compared with 36% of patients in the control group.

Furthermore, a greater satisfaction with knee function was found among the control group at baseline and follow-up, while the research team noted no differences in the rate of other injuries between the two groups.

“Our results point to an unacceptably high rate of new traumatic and non-traumatic knee injuries among female soccer players with [ACL reconstruction] ACLR,” the authors commented: “High-quality research is required to identify which factors increase or decrease the risk for sustaining additional knee injuries. This information may subsequently help to inform the development and implementation of injury prevention strategies.”

Are the results alarming for female athletes with ACL injuries?

My concern is when patients get self-selected by presentation. A significant proportion of ACL injured patients are those who were at high risk from the beginning, because of unfavourable constitutional mechanics. Having selected themselves, by definition, they are unfortunately at higher risk of it happening again despite potentially ‘successful’ and well-performed surgery. Throw into that the poor guidance on achieving the requisite return to sport, in a field which is still in its infancy, and you have quite a potent cocktail.

If you’re concerned you’re suffering from an ACL tear and want to arrange a consultation with Mr Jonathan Webb at either his London or Bristol clinic, call 0203 195 2443.

knee replacement longevity

New data reveals your knee replacement could last longer than previously thought

Knee replacement surgery has become one of the most common procedures performed in the UK, with nearly 200,000 of them performed in England and Wales alone in 2017, and for good reason – we have an ageing population who still want to stay active for the rest of their life. We know what they do, we’re making technological breakthroughs year upon year, and we know they work – but we’re still a little in the dark when it comes to their longevity, as the procedure is still in its relative infancy and there has been very little data on their long-term effects.

Well, that’s starting to change. And according to a comprehensive study on knee and hip replacement surgery conducted by researchers at the University of Bristol, there’s a lot more life in the replacements than first thought. The study harvested data from Australia, Finland, Denmark, New Zealand, Norway and Sweden – countries which have kept records of procedures over 15 years – and combed the details of over half a million procedures.

Their conclusions: as many as eight out of ten knee replacements and six out of 10 hip replacements last as long as 25 years.

A replacement that doesn’t need replacing?

The findings, which were published in The Lancet, demonstrated that hip and knee replacements are lasting much longer than originally believed. When it came to total knee replacements, the study concluded that 93% of them lasted 15 years, 90% lasted 20 years, and 82% lasted 25 years and over. Interestingly, partial knee replacements don’t last as long: 77% of them lasted 15 years, 72% lasted 20 years, and 70% lasted over 25 years.

According to the research team, these findings can help patients and surgeons decide upon the optimum time for surgery. “At best, the NHS has only been able to say how long replacements are designed to last, rather than referring to actual evidence from multiple patients’ experiences of joint replacement surgery,” said Dr Jonathan Evans, the lead study author and research fellow at Bristol Medical School. “Given the improvement in technology and techniques in the last 25 years, we expect that hip or knee replacements put in today may last even longer.”

While UK data wasn’t used in the research – simply because our record of patients does not go back far enough – the research team pointed out that their findings matched results from smaller studies of UK patients.

Good news for new knees

This is a very important development because it could force the medical community to rethink its position on replacement surgery. At present, the way of thinking is to delay the procedure until absolutely necessary, in order to avoid a replacement of the replacement down the line. Therefore, if the initial replacement is capable of holding up for far longer than first thought, it means that hip and knee replacements can be prescribed earlier in life.

And on a personal note, as I’m looking to have my own knee replaced in the next year or so, the thought of my replacement lasting a quarter of a century is great news. And I’m predicting that the replacements we’re putting in with the aid of the MAKO robot – which are better balanced – should last even longer.

For more information on the benefits of robotic-assisted knee replacement surgery, call 0203 195 2443 to arrange a consultation at Mr Jonathan Webb’s London knee clinic.

Knee Joint Injury

How a knee joint injury leads to knee arthritis

With Dylan Hartley being ruled out of the Six Nations with what his club called ‘grumbly knee’ and his doctor pinpointed as something worse, the spotlight shines once again on sporting knee injuries – and their knock-on effects. And a new study bears out the undeniable link between knee injuries of today and the problems it can bring on tomorrow; pinpointing the effect that knee injuries can have on the joint, and why it can lead to knee osteoarthritis later in life.

The study – a collaboration between the University of Eastern Finland and the Massachusetts Institute of Technology – demonstrates that articular cartilage degenerates specifically around injury areas when the fluid flow velocity becomes excessive. The findings, which were reported in Scientific Reports, presented a new mechanobiological model for cartilage degeneration, by implementing tissue deformation and fluid flow as mechanisms for cartilage breakdown when a normal dynamic loading – such as walking – is applied to the joint.

A new model that could make a real difference

The researchers discovered that different mechanisms, such as fluid flow and tissue deformation, have the potential to cause cartilage degradation after a knee injury. According to the research team, fluid flow and tissue deformation are plausible mechanisms leading to osteoarthritis, but increased fluid flow from cartilage seems to be better in line with the experiments.

Why is this important? Because this new model could be used to predict osteoarthritis in personal medicine, which would be a huge boost to the medical community: if doctors can be armed with more refined data, they could have a better shot at mapping out the best possible rehabilitation protocol. Furthermore, this model could identify high and low-risk lesions in the cartilage for osteoarthritis development and suggest an optimal and individual rehabilitation protocol.

“Our findings indicate that after an injury in the knee and subsequent tissue loading, osteoarthritis is caused by easy leakage of proteoglycans through the injury surface by high fluid outflow,” Gustavo A. Orozco of the University of Eastern Finland explains.

Taking a knee to long-term problems

Obviously, this isn’t going to help Dylan in the short term – and, like other athletes who have succumbed to knee injury, he is highly likely to suffer the consequences of arthritis as a result of his injury. In a 2017 study of retired rugby players studying concussion, the secondary outcome was that there was a high prevalence of arthritis, due to the fast, hard-contact nature of the sport and the stress it places on the knees.

And as we know, not only do knee injuries have the potential to cause osteoarthritis in the future, but so can the operations to put knee injuries right, including cruciate ligament repair and meniscectomy procedures.

Therefore, any new developments in the field of knee treatment are to be welcomed in both the short and long term – not only for the benefit of the sport, but for the athletes concerned when they are long into their retirement.