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Hip and knee replacements are among the most common orthopaedic procedures performed today, with some 160,000 being carried out each year in England and Wales. When being faced with the possibility of having to have one of these procedures patients often ask:

What is osteoarthritis, why do we develop it in our hips or knees and what are the symptoms?  Osteoarthritis (OA) is joint degeneration usually caused by overload as a result of being overweight, excessive sports activity, abnormal gait pattern and/or insufficient cartilage quality which is determined by our genes.           

Typical symptoms are progressively worsening pain & stiffness in the joint. The pain frequently gets worse after walking or any other physical activity involving the joint. Sometimes we can also experience pain at night.


What can we do to prevent hip or knee osteoarthritis?  Looking after our joints is important if we want to prevent OA. 

Excessive and chronic loading of the cartilage as a result of being overweight or sports activity can be damaging. We don’t know for certain if diets or drugs can reduce the risk of joint degeneration but, as the scientific evidence is weak, it’s likely that any influence at all is negligible.           

Some patients can have an anatomical abnormality leading them to OA. Hip impingement and instability (dysplasia) and knee instability (traumatic ligament injury) are the most common. Conservative joint surgery to correct these conditions is very important and should be carried out before the joint has started to degenerate.


When is the right time for a joint replacement and what can I expect?  When OA has developed, conservative surgical treatments are not effective and only a joint replacement is a reliable therapeutic option.

As any surgery carries some risks, it is important to carry it out at the right time. This is when medical treatments such as pain-killers, assistive devices and joint injections are ineffective and the impact on your quality of life is enough to accept the risks of surgery.        

The goal of modern joint replacement is to relieve pain and stiffness from the arthritic joint to substantially improve quality of life (QOL). It is difficult to estimate how long a hip or knee replacement will last but the probability of needing a revision is less than 20% for as long as 20 years after surgery and the vast majority of patients will never need one.


What are the latest improvements in hip and knee joint replacement?  Major advances have resulted in tools which enable surgeons to perform surgery with higher precision including robotics, computer-assisted surgery, patient-specific instruments, and soon augmented reality.

Improvement in precision is important but only if your surgeon has planned the right approach for positioning the new hip or knee.

There are revolutionary new techniques for the joint replacement itself. For decades new joints were positioned in a systematic way, much the same for every patient and without regard to the patient's specific anatomy.

This ensured good long-term implant survival rates but unfortunately at the cost of considerable complications. With modern implants, advanced implantation tools and a better understanding of joint replacement and biomechanics, new kinematic alignment techniques permit tailor-made positioning of implants. These techniques have recently been developed and are showing very promising results.

Looking to the future, as surgeons get more and more hyper-specialised, they will be able to reliably perform multiple different surgical techniques and provide "à la carte" tailor-made surgery. This will mean that every step of the operation is selected to best fit the patient and so result in the best possible clinical outcome.


How to choose your hip and knee surgeon? The starting point must be to check out your surgeon's reputation. Recommendations from friends, GPs and physiotherapists are always valuable. Online reviews are becoming more and more popular and are a very informative way to assess the quality of care.        

You should also check for any relevant research recently published by the surgeon as this will be excellent proof of his or her knowledge of the latest developments and advances. 


Which hip replacement will last the longest? Hip arthritis is the commonest cause of hip pain in Patients 50+. It is most commonly due to wear and tear of your hip joint cartilage. When the cartilage is completely worn out the only treatment is hip replacement or resurfacing. Currently, surgeons do not know which type of hip replacement will last longest. Metal on metal, ceramic on ceramic or metal on polyethylene. There are also decisions to be made about uncemented or cemented, femoral head size and the type of surgery. Each has advantages. Metal on metal is the only solution for hip resurfacing. Ceramic on ceramic has the best wear rate and biocompatibility. Metal on polyethylene has the longest clinical use. The decision about what will suit you best is made after a clinical assessment, imaging scans and the very latest knowledge from medical research about risk factors and success rates.


What to do about knee pain. Over 70,000 knee replacement operations are carried out every year and the number is increasing. Most Patients are over 65 and slightly more than 50% are women. You may not need a full knee replacement and may be suitable for smaller and better performing partial knee replacement.

The surgery is normally only appropriate if you have severe pain, serious mobility issues and if your arthritis is not responding to medication, physiotherapy and weight loss. The earlier you have a knee replacement, the greater the chance that you will eventually need further surgery, but there is now some evidence that not waiting for your knee to become very stiff leads to a better result.


What are the advantages and disadvantages of knee replacement? Obviously, freedom from pain is the main benefit and you should find that you are more mobile as well. About 9 out of 10 people say that they are happy with their new knees. Everyday activities become much easier and exercise such as swimming, cycling, tennis or golf are also usually possible. You may be aware of some clicking in the joint, but by far the majority of people rate their new joint at about 75% normal. The good news is that most artificial knees will last for 20 years plus.


The web contains very useful information which will interest you. Here is a small selection.

American Academy of Orthopaedic Surgeons

Arthritis Rsearch UK

Best Health

British Orthopaedic Association

Royal National Orthopaedic Hospital

The Bone and Joint Journal

The British Hip Society

The Great Debate