hip replacement dislocation

When a patient has been recommended for a total hip arthroplasty (THA, also known as a total hip replacement) one of the most common complications in the years following the surgery is hip dislocation. The NHS reports that this happens in around 10% of cases. This is a frustrating complication for all involved and it is not always immediately obvious what the cause of dislocation is.

Hip replacement dislocation: the patient has had a lumbar fusion

A lumbar fusion is an operation designed to help patients who have spinal problems, specifically it fuses together two or more of the tiny bones in the spine, the vertebrae, so that they work together as one fused bone.

The aim of this is to stop the movement between these bones in cases where their natural alignment is causing the patient pain and impaired mobility. In a huge study conducted using patient data gathered between 2005 and 2012, the Bone and Joint Journal reports “patients with a previous history of lumbar spinal fusion have a significantly higher rate of dislocation of their THA than age- and gender-matched patients without a lumbar spinal fusion.”

More research is required to establish what can be done to reduce the risk of dislocation following THA in patients who require or have had a lumbar fusion. Patients requiring either surgery will no doubt be in serious discomfort, with limited or no other options to fix the problem, other than via these methods.

Hip replacement dislocation: the patient has decreased spinopelvic motion

According to a report published recently in the Journal of Bone and Joint Surgery, dislocation following THA is also much more common in patients who have a spinopelvic imbalance – in layman’s terms, the tilt of the pelvis and the angle of the spine are misaligned, causing unnatural wear and tear on hip joints. This issue is exacerbated if coupled with either cup malposition or soft-tissue abnormalities.

The results came from a 20-patient study where all had suffered dislocation following a THA and, as such, data was examined to understand what factors could have caused the joint to dislocate.

Looking to understand hip replacement dislocation more clearly

Whatever the cause of the dislocation, hip replacement surgeons will welcome more research into this issue as when it does occur it will often require revision surgery (surgical intervention to replace or fix the joint again). Typically, dislocations of this nature occur between 10 and 15 years after the initial operation, but in rare cases, this can happen very soon after surgery. If you have undergone a THA and have any concerns, then consulting your hip surgeon quickly will ensure you are in the best hands to assess the problem and to agree the most suitable course of action.

Revision hip surgery is much more challenging than the initial procedure; Mr Simon Bridle combines surgical expertise with clinical experience and specialist training to deal with complex revision cases and has performed many of these procedures over the years.

hip resurfacing or hip replacement

If you’re a tennis fan then it will not have escaped your notice that Andy Murray has been having some difficulties recently, and these are being caused by repeated injuries to his hip joint which have finally developed into osteoarthritis.

Murray has been suffering with the build-up of this condition for around a decade, and although he has been able to make some adjustments to his game to mitigate the pain, it has reached a point where the pain is now debilitating. This painful condition has caused the former tennis ace to scale things right back and announce his retirement from professional sport and decide to have a hip resurfacing procedure.

This is an interesting course of action, as the feeling of London hip surgery expert Mr Simon Bridle is that although this technique is widely available, it is largely unproven in terms of the benefits it brings. Here we look at some of the reasons people may opt for hip resurfacing, and some of the challenges associated with it.

What is hip resurfacing?

The technique involves identifying where the bone is rubbing together, as this is what is causing the severe pain. The surface of the bone is then replaced with metal on both surfaces, so that the metal rubs together, not the bone.  An article published in the New Scientist explains the theory: “Rather than bone rubbing against bone, causing severe pain, metal rubs against metal – while a significant amount of the patient’s original bones around the hip area remain intact.”  The technique became very popular in the early 2000s, especially in younger patients.  However, some implant designs performed poorly and this led to a high revision rate and far fewer of these procedures being done.

Myth busting hip resurfacing

  • Hip resurfacing is a smaller operation?

This is actually not the case. Although the work that is done to the existing hip bone is lesser, the surgery to put in the new metal surfaces involves the same amount of invasive surgery as a total hip replacement, as full access to the affected hip joint is still required. The procedure simply takes less of the bone away – in total hip replacement both the top of the thighbone and the socket it which is sits are replaced with artificial materials, whereas in hip resurfacing the head of the femur is typically smoothed down and covered with a metal cap and a layer of metal is placed in the pelvic socket.

  • There are fewer risks associated with hip resurfacing?

This is also a common misconception and not proven. The immediate operative risks are the same.  The biggest concern with hip resurfacing remains the generation of metal debris, which can damage the bone and local soft tissues and also migrate into tissues throughout the body.

  • Hip resurfacing allows higher levels of function

 There is little evidence that hip resurfacing performs any better than conventional hip replacements. Most surgeons will allow patients to return to similar levels of activity, no matter what type of hip has been put in and the type of hip seems to make little difference to the sporting activities which patients are able to return to.

Increased interest in hip resurfacing is inevitable

Nevertheless, the publicity associated with a high-profile sports star like Andy Murray choosing this treatment for his hip osteoarthritis means that awareness of hip resurfacing will grow again. If you are weighing up the decision of a hip replacement versus hip resurfacing, you can expect to find a plethora of information about Andy Murray’s experience and his decision to opt for hip resurfacing. We would strongly recommend speaking with a hip surgeon before making the final decision.

hip replacement longevity

A common question asked during a knee or hip replacement consultation is how long will my artificial joint last. With growing numbers of younger, more active men and women presenting with joint pain and lack of mobility due to wear and tear, the potential hip replacement longevity has never been so important.

Previously thought to last 15 to 20 years, continuing development of implant materials, prosthesis design and improvement in surgical technique, means that your new hips and knees may last considerably longer. This has been confirmed by a large-scale study that has recently carried out by the University of Bristol.

Up till now, there has been limited data on the longevity of artificial joints, so London hip replacement expert Mr Simon Bridle welcomes this study. Its findings will help him provide more definitive data when assisting patients to make the decision as to whether to go ahead or not with surgery.

Hip replacement longevity examined

Published in the Lancet, the researchers analysed 25 years’ worth of operations, performed on over 500,000 patients. Lead study author and research fellow at Bristol Medical School, Dr Jonathan Evans said: “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.”

The study discovered the following:

  • Hip replacement: 89% lasted 15 years, 70% lasted 20 years and 58% lasted 25 years
  • Total knee replacements: 93% lasted 15 years, 90% lasted 20 years and 82% lasted 25 years
  • Partial knee replacements: 77% lasted 15 years, 72% lasted 20 years and 70% lasted 25 years

Interestingly, the UK joint replacement registry data didn’t go back far enough to be used in the study, so the researchers looked at data from Australia, Finland, New Zealand, Norway, Sweden and Denmark. However, they confirmed that their findings mirrored results from previous smaller-scale studies carried out in the UK.

Inevitably this data relates to the performance of joint replacements using older implants and materials.  There have been considerable advances in implant technology over the years, in particular with bearings with a far lower wear rate, so there is every hope that hip and knee replacements put in today will do even better than this study suggests.

As the population ages and lives longer, combined with a growth in younger patients that are experiencing increased joint wear and tear, the news that our hip or knee replacements will last longer and require fewer repeat operations is great news.

If you’re contemplating joint replacement surgery and wish to discuss all aspects of the procedure in full, call 020 8947 9524 to book a consultation with Mr Bridle.

obesity and hip replacements

Shocking figures illustrating the impact that the UK’s obesity crisis is having on the NHS were recently disclosed by an investigation carried out by the Sunday Times. The paper revealed that more than 41,000 obese people required hip or knee replacement operations last year – including seven teenagers.

The investigation found that the numbers of obese patients requiring joint replacement surgery had increased from 6,191 in the period 2009 to 2010 to a staggering 41, 671 in 2017 to 2018. This surge – amounting to a 575% increase – costs the NHS £200 million a year. It was found that obesity was the main or second most important factor for 25,577 of patients last year undergoing a joint replacement surgery. Another 16,184 patients had obesity as a primary or secondary diagnosis.

Obesity and arthritis

Osteoarthritis is the result of wear and tear on our joints and, simply put, any excess weight adds more stress on our joints. Therefore, a common health condition relating to obesity is the development of arthritis.
Joint replacement surgery can be a highly effective way to relieve the symptoms of arthritis; joint pain and lack of mobility but, at the same time, obesity can raise the risk of complications relating to joint replacement surgery.

Obesity and hip replacements – the possible complications

A recent study carried out by the Mayo Clinic in the US concentrated on joint surgery-related complications and their relation to BMI or body mass index. Looking at data relating to 21,000 joint replacement procedures, they focused on revision surgery, whether that’s due to problems with the original implant, early dislocation or joint infection.

The researchers found that the risk of revision surgery increased in almost a linear fashion along with the patient’s BMI – each additional pound over the optimal weight for your height increased the risk of revision surgery.

Outcome for obese patients

Interestingly, a study carried out in 2017 by the University of Massachusetts Medical School in the US found that obese patients who underwent knee or hip replacement surgery reported virtually the same pain relief and improved function as normal weight patients after six months.

The large scale study, published in the Journal of Bone and Joint Surgery, found that while obesity can increase the risk of complications associated with surgery, it shouldn’t necessarily be a deterrent when contemplating joint replacement surgery to relieve the symptoms of joint wear and tear. Function and pain were evaluated in over 5,000 patients, categorised as normal weight, overweight, obese, severely obese and morbidly obese. The more obese the patient, the worse pain and function were prior to surgery, yet after surgery, the pain scores were similar across all BMI levels.

So, some good news for those patients who are overweight and struggling with joint pain and lack of mobility to commit to an exercise regime. However, trying hard to lose weight in advance of surgery should always be the preferred option as this is likely to make surgery safer. In addition, of course, there is also a link between obesity and a whole host of health concerns, including diabetes, high blood pressure, heart disease and cancer, as well as the development of osteoarthritis.

hip-knee mechanics and joint pain

Many people suffer from osteoarthritis and, contrary to popular misconceptions, it is not just a condition that affects older people. In fact, it is believed to affect between 12 and 15 per cent of the population who are aged between 25 and 74. It is much more prevalent in older people, but its presence in younger men and women as well means that there are a variety of causes which are not just explained by the natural ageing process and the inevitable wear and tear on joints as we get older.

According to a report published by the National Center for Biotechnology Information (NCBI) in the US, factors that affect patients’ likelihood to develop osteoarthritis are vast. These range from genetics and molecular structure, to what is described as environmental factors such as ‘biomechanical stress’. What this means is the stresses and strains that are put on people’s knee and hip joints through the lifestyles that they choose to live. Scientists are of the belief that biomedical stresses play a highly significant role in the likelihood of developing osteoarthritis.

The right balance needs to be struck

It is widely accepted that certain lifestyle activities can increase the chance of developing osteoarthritis in joints like the knees and hips. High impact sports, for example, especially those with very repetitive motions, have been linked with the development of the condition. It is a delicate balance that needs to be struck, though, as conditions such as obesity are also proven to be linked with the development of osteoarthritis.

Data that has contributed to this includes a study of 506 young female athletes in the US. The study looked at this group because their lifestyle choices suggested that they could be in a higher risk bracket for developing osteoarthritis. The results concluded that there were indeed patterns to be seen in the development of the condition in girls who had been impacted by ‘biomechanical stress’ on their joints, both during pre-puberty and when they were nearing adulthood.

Data such as this is particularly interesting to researchers, as it has been proven that women are at a greater risk than men of developing injuries to their knee and hip joints as a result of environmental factors, compared with men. The Journal of Orthopaedic and Sports Physical Therapy looks in detail at the factors that affect degeneration of the knee and hip joints and concludes that environment factors, coupled with gender, can be regarded as ‘red lights’ in terms of risk categories for those undertaking strenuous sports “the knee has been reported to be the most common site of overuse injuries in runners, 74 triathletes, 18 and military recruits ….. females sustain a higher number of traumatic and overuse knee injuries when compared to males.”

The benefits of understanding more about biomechanical stresses

Identifying these trends gives medical professionals the knowledge and statistics required to ensure that preventative steps to ensure that those in higher-risk categories are educated accordingly and advised of the risk associated with their lifestyles.

Sometimes, a relatively simple chance to how people are living can make a big difference in terms of their propensity for developing conditions like osteoarthritis. The report authors summarise some of the benefits in this type of case: “Female athletes may benefit from hip targeted exercises prior to puberty and more global (hip and knee focused) neuromuscular training following pubertal maturation to reduce their risk to develop PFP [patellofemoral pain].”

hip implant technology

Researchers at the University of Warwick have been working to develop a new device which helps identify patients who have more ‘flex’ than they should do in their pelvis. These people are at a higher risk of developing problems with prosthetic hip joints following surgery (especially issues such as dislocation), so with the help of this device, patients would be able to take steps to ensure that the flex in the hip joint does not put their new hip replacement joint under unnecessary stresses. It would essentially ensure that surgeons are fully informed of who is most at risk and take steps accordingly to mitigate.

As things stand currently, surgeons are aware of the increased risk for people with this type of pelvic position, but it is time-consuming and more difficult to diagnose: “Patients who have pelvises that rotate large amounts during movement are at higher risk of dislocation, particularly if the replacement hip is not fitted accurately. Those patients can receive a more advanced surgical plan, but it is currently difficult to identify who requires this without a number of time-consuming and expensive x-rays.”

The new pelvic tracking device is able to detect immediately which patients have high levels of ‘pelvic rotation’ and to ensure that this is woven into their surgical plan and aftercare. Not only does this device have the potential to help ensure that the quality of care is aligned more closely to patients’ needs, the speed at which the diagnosis is possible means that it also provides a significant cost saving.

Dr Mark Elliott explains, “this new device has been developed to allow surgeons to screen patients for a flexible pelvis in a matter of minutes, identifying those who are at increased risk of complications if it is not fitted accurately. This will hopefully reduce costs and save time by identifying those patients who require more accurate surgical procedures. The research team working on the project have created a design and algorithm that can accurately track the pelvis movements comparable to that currently measured by x-rays.”

The device has been available for surgeons to test out first hand at the recent British Orthopaedic Association exhibition in central Birmingham, which allowed the device’s creators, a company called Corin, to explain the benefits they believe the device can bring to patient care and surgical outcomes.

In terms of future proofing hip replacements for patients with overly flexible pelvises, this is a clear step in the right direction in terms of the evolution of medical technology in this area. There are other exciting developments too which would work in tandem with this, such as the MAKO robotic-assisted hip replacement surgery. This technology allows surgeons to scan patients and output a bespoke 3D model of the affected area, which gives them a unique opportunity to design the patients’ surgical plan especially around the issues that they are struggling with. The benefits of these improved technologies are that there is a much greater likelihood of getting it right first time, which leads to fewer issues such as dislocation, and less of a requirement for revision surgery to correct work done on less informed patient assessments.

Mr Simon Bridle is one of the first orthopaedic surgeons in London to be able to offer his patients robotic-assisted hip replacement surgery. Call 020 8947 9524 to find out more.

hip implant dislocation

Hip and knee replacements are recommended for over 150,000 patients every year in the UK, and they are proven to improve mobility, quality of life and reduce pain for many people who are struggling with issues affecting their original joints. They have been practiced by surgeons for decades and are very successful, but as with everything, over time they can be subject to continued wear and tear and can begin to deteriorate.

Issues with hip implant dislocation and the subsequent challenges this brings

For patients who have undergone a total hip replacement, one of the issues that they could face in the years following the surgery is dislocation of the replacement joint and as a result, surgeons are always looking for methods, techniques and materials that can help reduce the risk of implant dislocation.

Dislocation is an issue that is more prevalent in patients who have had more than one hip replacement, a process known as ‘revision surgery’. There is now a new type of artificial hip joint called a ‘modular dual mobility’ joint, which has been proven to reduce the risk of revision surgery as a result of dislocation.

A report published recently by an orthopaedic hospital in the US explains the difference of a modular dual mobility joint and how this compares more favourably to the traditional method: “Modular dual mobility implants provide an additional bearing surface compared to a traditional implant. With the dual mobility hip, a large polyethylene plastic head fits inside a polished metal hip socket component, and an additional smaller metal or ceramic head is snap-fit within the polyethylene head.”

The findings of this new report are from a study undertaken by Dr Geoffrey Westrich and his colleagues at the Hospital for Special Surgery, a leading academic medical centre for musculoskeletal health. The study comprised data from 370 patients who underwent revision hip surgery and had a dual mobility implant. Data was collected between April 2011 and April 2017. The research assessed data from a variety of different perspectives, including clinical information, radiographic data and patient reported-outcome information.

Impact for Mr Bridle’s hip replacement patients

Mr Bridle is in support of the benefits of using a dual mobility sockets, with the first-hand experience of the benefits this brings to his patients. He agrees that the greater risk of instability seen with high risk and more complex revisions is reduced when using this type of socket. Not only are these sockets better for those who are at risk of revision surgery. Mr Bridle also favours this type of artificial joint when treating patients who are undergoing total hip replacement for the first time but who have one or more factors which put them in a higher risk category. Risk factors that mean patients would benefit more from a modular dual mobility joint include conditions such as chronic back problems, spinal fusion or certain neurological conditions.

For more information on dual mobility hip replacements, call 020 8947 9524 to arrange a consultation.

depression and arthritis

Scientists are always looking for links between conditions, as a way of understanding how and why they interact and establishing the cause and effect of different disorders. The results of an interesting new study have found hip arthritis is more prevalent in those suffering from depression – for many years it’s been thought that depression is a risk factor for those suffering from joint pain but now the suggestion is that the converse might be true.

What came first, chicken or the egg?

The challenge for scientists has always been establishing the order effect of these conditions. There has been a recognised overlap between these two conditions for many years, as both are prone to affect people as they get older. Arthritis causes symptoms such as pain and restricted mobility, and due to its degenerative nature, this can cause many sufferers to feel depressed.

However, researchers have recently published findings suggesting that those first suffering from depression are much more likely to develop arthritis. The research team, based at Dartmouth College in the US, revealed: “arthritis is more common among depressed patients than those who were not suffering from the mood disorder, suggesting that depression may be a risk factor for arthritis, too.”

The research team assessed data from almost 5,000 patients over the age of 50 and looked at those who were diagnosed as having mild, moderate and severe depression, and also a control group of those without. The links they found were conclusive, those with more severe depression had a direct correlation with the incidence of arthritis.

The concern for medical practitioners is whether or not patients are receiving suitable care for both of these complaints in parallel, as many experts are concerned that the mental wellbeing of patients may be overlooked is favour of treating the physical symptoms associated with recovering from operations related to arthritis in hip joints.

Jessica Brookes, PhD, from the Geisel School of Medicine and Centres for Health and Aging comments “depression is highly prevalent yet one of the most undertreated and poorly understood psychosocial factors associated with arthritis, with nearly half of older adults with both chronic pain and depression receiving either inadequate or no mental health care.”

Interesting overlap between mind and body

The links between mental and physical conditions are fascinating and research into the connections between the two can enable scientists to learn much more about the body and mind and how they affect one another. “The more we learn about various diseases traditionally thought to ail the body and the mind, respectively, the more scientific study supports the notion that the two categories are not so separate.”

It has long since been recognised that your mindset can play a really important role in recovering from any illness, as a positive mental attitude and positive outlook can have a surprising effect on your overall wellbeing.

People who approach their recovery from operations such as total hip replacements with a positive attitude have been found to enjoy a quicker recovery period compared with those who adopt a more negative mindset. The Journal of Bone and Joint Surgery reports “it is well established that the emotional health of the patient influences the outcome of many common orthopaedic surgeries… Poor functional outcomes [of orthopaedic operations] have been correlated with poor emotional health, such as anxiety, depression, anxiety, poor coping skills and poor social support.”

women and hip replacement surgery

Typically, when we think about hip replacement surgery, we think of the older generation, as this demographic were historically much more likely to need medical intervention to help problems associated with ageing joints. But it seems there has been a surge in the number of younger, female patients who require this type of operation. Women’s Health recently reported that “hip replacements have increased 40 per cent among 45- to 54-year-olds”. So, why might this be?

Women and hip replacement surgery: increased interest in high impact sports

Over recent decades, women have been converts to high impact exercise routines, such as running or HIIT, better known as high intensity interval training, all of which put pressure on joints. Recreational jogging and competitive sports such as 10ks, half and full marathons have grown in popularity, but over time, these impact sports can wear away at joints, leaving them prone to degeneration at a younger age.

Although this isn’t just a problem for women, anatomical differences between men and women mean that a number of impact-related hip conditions are more likely to affect women.

An example of this is a condition called femoroacetabular impingement (FAI), which is where the ball and socket joint in your hip becomes misaligned and begins to cause friction, wear and, ultimately, arthritis inside the joint. Women are also more prone to hip dysplasia, where the socket of the joint is shallow and this also predisposes to the development of arthritis. Women’s gluteal muscles have to compensate more for these anatomical differences, and if they don’t, then problems can begin to develop.

Women and hip replacement surgery: advances in technology

The knowledge we have about the different conditions that can affect hip joints, and the ability of modern technology to aid in effective diagnosis, has improved significantly over time. Previously, conditions that affected hip mobility in otherwise young and healthy females could have been misdiagnosed as groin or muscle problems, and therefore would not have been treated effectively.

Armed with greater understanding now of what causes degenerative hip conditions, and the knowledge of the differences male and female biology has on the likelihood to develop problems, surgeons are much more adept at making quicker and more accurate diagnoses.

Women and hip replacement surgery: what to do next?

Balancing high impact exercise with workouts that strengthen the muscles around the hips is key to supporting your joints. Strengthening these key muscles can help give a protective cushion around your hips, which won’t remove the risk entirely, but will certainly help.

It is never too early to consult an expert if you are worried about your hip joints, because if you have been experiencing pain for a period of time and you are not able to manage to this pain adequately with over-the-counter anti-inflammatory drugs or you are finding that your mobility is restricted, then it is probably time to have a proper medical assessment with a hip specialist.

infection and revision joint replacement

Hip replacement surgery is a very common operation nowadays with an excellent success rate. Over 100,000 patients per year undergo this type of operation, and it is commonly used to treat chronic, debilitating conditions such as osteoarthritis. Total hip replacements are proven to make significant improvements to quality of life, including mobility, reduction of pain and an improvement of patients’ general well-being, but as with all surgeries, there is a small risk of complications developing post-operatively.

One risk is that patients could develop a prosthetic joint infection, or PJI. This is a rare complication, affecting around 1% of patients.  The consequences of a PJI are not to be underestimated.  A study from Bristol University published in the Lancet Infectious Diseases medical journal describes it as a ‘devastating complication’ following joint replacement surgery.  A PJI can lead to “severe pain, poor function, reduced quality of life, and even death.” Treatment to cure a PJI can also be tough and gruelling for patients and usually requires revision joint replacement surgery to get rid of the infection.

With this in mind, a cohort of doctors have been analysing data collected over many years of joint replacement surgery to see whether they can identify patterns of who might be at greatest risk of developing a PJI following surgery for total hip replacement.

Risk factors for infection and revision joint replacement

The study used data from the UK National Joint Registry over 11 years and concluding in March 2018, with over 600,000 cases.  Risk factors for the development of PJI were identified.

The following were identified that correlated with a higher chance of developing a PJI:

  • Younger patients (under 60 years old)
  • Patients with a high BMI
  • Those already reporting chronic pulmonary disease, liver disease, or dementia
  • Hip replacement performed for a hip fracture

These factors seemed to reduce the risk of infection:

  • The use of a posterior approach
  • The use of ceramic as the bearing material

This news is encouraging and supports the approach undertaken at Mr Simon Bridle’s London hip replacement clinic as he prefers to operate using the posterior approach and using ceramic bearings for the artificial joints.

These results give a very clear steer regarding heightened risks for certain groups of the population and, armed with this information, surgeons are able to more accurately advise patients and can take steps to help manage/reduce the associated risks for these groups. Work will now be undertaken to understand whether the same patterns are identified for patients who undergo knee replacement surgery, to see if there are parallels found between the two types of operation.