What is a hip replacement?
A hip replacement is a surgical procedure designed to replace the ball joint and re-line the socket joint.
It is most commonly performed for osteoarthritis, where the cartilage layer over the ball/socket is worn away.
Hip impingement is now known to be one of the most common causes of osteoarthritis and hip replacement.
Less commonly it is performed for other conditions such as hip dysplasia, rheumatoid arthritis, Perthes disease and avascular necrosis or due to injuries.
Common features of osteoarthritis of the hip:
Pain felt in the groin, thigh, buttock and often down to the knee
Pain gets worse with walking or exercise. Often remains for several hours afterwards
Patients often complain of a limp.
People/relatives may comment on your walking
Joint stiffness with difficulty in getting shoes/socks on.
Can be effectively controlled with simple painkillers and anti-inflammatories in its early stages
Do I need one?
There are generally 2 criteria for needing a hip a replacement:
That the a part or the whole of the hip joint is worn out either on X-ray or MRI scan
That you are still having pain despite exhausting all other treatments such as pain killers/physiotherapy/walking aids
These have to be balanced against the surgical risks, which are patient-specific.
How it is done?
There are a variety of ways in which surgeons access the hip joint. However, some approaches such as the lateral approach can damage the major muscles used for walking and are best avoided.
The most common surgical approach used in the UK is through the back of the hip joint (the posterior approach). This prevents damage to any of the important muscles around the hip.
We also use a more modern version of this approach called the Direct Superior Approach, which avoids cutting any major muscles around the hip. This may enable a faster recovery and a return to sporting activities at an earlier stage.
Many patients ask about the size of their incision (scar). In general, we keep the incision size to an absolute minimum, but make it large enough in order to be able to access the hip joint safely. We always use dissolvable sutures, which helps minimise scarring and improve the cosmetic appearance.
In general it takes between 45 minutes and 1.5 hours (depending on complexity) to perform a hip replacement.
The vast majority of hip replacements are performed using a combination of a spinal anaesthetic and sedation. This involves placing a small injection in the spine, which completely numbs the patients legs from the waist down. This is done in the anaesthetic room. The patient is then given sedation, which drifts them off to sleep. Patients are generally not aware of the surgery and have little or no recollection of going into the operating theatre. This type of anaesthesia has been shown to reduce blood loss (transfusion is now rare in hip replacement), blood clots and other complications.
Patients will generally meet their anaesthetist on the morning of surgery, who will go through the anaesthetic in detail. Our anaesthetists are typically highly skilled intensive care specialists. We can arrange a pre-operative consultation with the anaesthetist for patients who have concerns about anaesthesia or who have medical problems. The Manor hospital has both High Dependency and Intensive Care facilities for patients with medical problems.
In some circumstances and with certain medical conditions, the anaesthetist will advise a spinal alone, or a general anaesthetic.
As part of the procedure we also use local anaesthetic and anti-inflammatory injections. These help minimise any discomfort for up to 8 hours after the surgery.
What types of hip replacement are there?
There are over 230 types of hip replacement available to surgeons. Most are well proven and work well, however not all designs are tried and tested or successful. The UK is at the forefront internationally of monitoring and developing new designs of hip replacement, through organisations such as Beyond Compliance and the England and Wales National Joint Registry.
Broadly speaking four types of hip replacement designs are available:
A fully cemented hip replacement- where both the socket and stem are fixed using bone cement. This is often used in older patients, where redo is unlikely, although good results have also been described in younger patients.
A hybrid hip replacement- where the socket is uncemented and the stem is fixed with cement. This is the most commonly used implant. Many of these designs have been around for over 40 year and have excellent long-term results. The disadvantage of any cemented component is that the cement can sometimes be difficult to remove and result in bone loss at redo surgery.
An uncemented hip replacement- where both the socket and stem are fixed directly to the bone. Uncemented hips are typically covered with a special coating, which encourages the growth of bone directly onto the implant. This starts to occur within the first 3-4 weeks following implantation. Many cementless stem and socket designs have excellent 30-40 year results. Some of the newer designs are scaled down versions of more traditional designs, these are therefore smaller and more bone-conserving. These may be more advantageous when it comes to redo surgery and may be indicated in younger patients.
Hip Resurfacing- This is a metal on metal hip replacement which has inferior outcomes to total hip replacement in most patients. It was originally marketed as a less invasive joint replacement, however this is not the case. Whilst resurfacing can perform well in younger men, it still carries a risk of a tissue reaction to the metal particles generated from the implant. Given these risks we do not offer hip resurfacing.
In general, most good surgeons would normally only recommend an implant that has good long-term results, or newer implants that are being closely monitored as part of the Beyond Compliance process (http://www.beyondcompliance.org.uk/). Watch this Beyond Compliance video for patients for more information: https://www.youtube.com/watch?v=MJWGTrlW5i8&feature=youtu.be
Another consideration in hip replacement is the bearing surface. This means the two surfaces that rub together, where the ball and socket meet.
In general there are 4 types of bearing surface:
Metal ball and plastic (polyethylene) socket lining- This is the most common type of bearing surface. Historically plastics used to wear out within 10-15 years. With the development of harder and more resilient plastics (known as Highly Cross-linked Polyethylene), which are extremely hard wearing, these bearings are now some of the most reliable and long-lasting.
Ceramic ball and plastic (polyethylene) socket lining- This combination further reduces wear compared to a metal on plastic bearing. It has the lowest risk of redo for wear in the National Joint Registry. Combined with Highly Cross-linked Polyethylene, this bearing surface is desirable for younger, more active patients. Studies have demonstrated that there is little or no detectable wear 13 years after surgery with this bearing combination.
Ceramic ball and ceramic socket lining- This is one of the hardest bearing surfaces and so wears the least. However ceramic on ceramic bearings can squeak and the thin ceramic liner of the socket can break on rare occasions.
Metal ball and metal socket lining (also known as metal on metal hip or hip resurfacing). These types of bearings are not widely recommended. Whilst they wear less than plastic, some patients (between 1 and 20% of people who have metal on metal hips) will have a reaction to the metal. This can often lead to local soft tissue destruction and rarely result in damage to bone/nerves/blood vessels. Metal on metal hips do not last as well as more conventional hips and many designs have been phased out over the past few years. However they may still be indicated in some patient groups. For more information see the British Hip Society Advice: https://www.britishhipsociety.com/News-Details?id=lQ%3D%3D and the National Joint Registry: http://www-new.njrcentre.org.uk/njrcentre/Patients/Jointreplacements/Hipreplacements/tabid/94/Default.aspx
How long will it last?
Hip replacements are one of the most successful surgical interventions ever devised. The national joint registry of England and Wales tracks all hip replacements and shows that over 95% of most hip replacement designs last 10 years or more. There is a 75% chance that a hip replacement put into a 50 year old today will last them for the rest of their life.
Are there any New Technologies on the horizon?
New types of hip replacement
The field of hip replacement is evolving continuously. Brand new implants are being introduced all the time. Cutting edge designs which have just been released within the past two years are not recommended for general implantation without being part of a monitoring process (such as Beyond Compliance) or part of a formal research trial.
Patients wishing to consider a brand new type of hip replacement need to understand that whilst most new implants perform as well or better than existing designs, some perform much worse. There may therefore be a risk in being one of the first people to receive a new type of hip replacement.
There are many newer designs of hip replacement that have been around for a little longer (5 to 10 years). These include smaller less invasive hip replacements known as ‘short stem’ or ‘mini hips’. Early studies suggest that some of these designs are likely to be very successful, they may also preserve more bone than conventional designs, making redo easier. Many are merely scaled down versions of well-proven designs.
In the UK all hip replacements are monitored by the National Joint Registry, which reports annually on the performance of all designs in our country.
More information on clinical trials and new implants can be found here:
3D preoperative planning and patient-specific biomechanical analysis
In Oxford we operate on a high proportion of younger and often older more active patients. Many patients will want to continue high level sports and regular exercise following their operation. Whilst hip replacement is very successful, we realise that many sporting activities can put extra stress on hip replacements. This in turn can lead to more wear and an increased risk of dislocation with some activities.
Recent research has demonstrated that the way peoples back, pelvis and hip moves is unique to each individual. Research has also shown that back problems and muscle weakness can have a huge effect on the stability and function of a hip replacement. Conventionally surgeons have aimed to place the hip replacement in a certain position for all patients. We now think that the ideal position for a hip replacement is unique to that individual. New technologies are now emerging that seek to identify this best position before the operation using scans and computer modelling. This is known as Patient Specific Surgery. By using an advanced computer model we can perform virtual hip replacements to assess the best position for a patients before their operation. We can then build special laser-guided 3D printed models to guide us to the chosen position during surgery. One such system is known as Optimized Position System. Early research shows that this system allows surgeons to accurately position a hip replacement in the ideal position.
The video and pictures show the different stages of this process
More information can be found here:
We are fortunate to be working with several leading universities and technology experts. One of the projects we have been working on is called My Recovery, this is an app for your phone which takes you through the stages of having the operation, helps you with exercises pre and post operatively and allows you to monitor your progress.
We encourage all our patients to take a look, more information can be found at https://www.myrecovery.ai/patient/
If you would like to enrol please email email@example.com stating
Your Mobile Number
Your operation type and date of surgery
Include the Reference ‘SGJ’
You will then be sent a welcome email with a download link for your new MyRecovery Phone App
What is the recovery time?
The recovery time from hip replacement varies considerably from person to person. Age, pre-operative fitness and related health problems may all have a significant effect. The timetable below gives a guide to the average recovery:
Hospital stay- 2 to 3 days, able to walk up a flight of stairs using crutches on discharge. Will have raised toilet seat and must avoid very low chairs and beds for 4 weeks minimum. Will be given blood thinning medications to take for 5 weeks and anti-blood clots stocking for 5 weeks.
Can lie on side in bed from 1 week onwards
Day 10 to 14 return to Manor or GP for wound check and trimming of stitch ends.
Weeks 1 to 4 short walks with crutches, moving on to walking sticks or one crutch when confident. Begin physiotherapy
Weeks 4 to 6-walking longer distances (up to 5 miles) using walking stick or crutches only for long walks.
Weeks 5-6 can begin driving- Patients need to try operating vehicle controls and then inform insurance company before driving on public highway.
Weeks 6 to 8- walking without sticks- increase physiotherapy intensity and begin gym work under guidance. Aim to gradually increase range of movement with only minor restrictions.
Week 10 can begin golf/cycling/swimming/pilates
Week 12 can begin tennis/exercise classes/yoga and higher intensity sports such as road cycling
Week 25 can go back to most sports as experience allows: including running/skiing/climbing/football
Generally speaking patients can stop using all sticks/crutches when they feel able to, provided the surgeon is happy with this. In some patients this may be within 2 weeks in others it may take as long as 6 weeks.
Patients will need to have injections or tablets to prevent deep vein thrombosis and blood clots on the lung for a period of 5 weeks after surgery. They are also advised to use compression stockings for 5 weeks.
What are the risks?
Serious complications are rare after hip replacement, however patients need to be aware of the following risks before undergoing the procedure. The risk is generally much lower for patients under 80 who are fit and well. The risks may be higher in patients with multiple medical problems
Frequent risks (5-10%): Mild to moderate bruising around the scar or thigh.
Rare or serious risks (1% chance or less): Infection, Blood clots (including deep vein thrombosis, and pulmonary embolism), Dislocation, Bleeding, Need for further surgery, Leg Length Inequality, Tendon injury, Wear and loosening of the hip replacement, Continued pain and stiffness/weakness, Extra bone formation (Heterotopic Ossification), medical problems (eg heart, chest etc)
Very rare (0.4% or less): Nerve and blood vessel injury, Death/Life Threatening complications.