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Knee Replacement Surgery Q&A

We asked three of our leading orthopaedic consultants about knee replacement surgery.

Matthew Bartlett
Consultant Orthopaedic Surgeon
The Clementine Churchill Hospital

Abdel Hassan
Consultant Orthopaedic Knee Surgeon
The Runnymede Hospital

Marcus Green
Consultant Orthopaedic Surgeon
The Priory Hospital
Sutton Medical Centre

What kinds of people get total knee replacement surgery? Why do patients typically require this surgery?

Matthew Bartlett

All kinds of people have knee replacement. There is no lower or upper limit on age although we approach younger people with more caution as they are likely to outlive their knee replacement and thus may need one or more revision operations.

The decision to operate is based around the pain and limitation that the knee is causing compared to the improvement a knee replacement would offer.

This is different for each individual - there is no universal answer and careful discussion with your consultant about replacement and its alternatives is always a good idea.

Abdel Hassan

When healthy, joint surfaces are as slippery as ice and we take the mobility for granted.

Patients need replacements of the worn surfaces when the soft cartilage is lost and the joint is painful, stiff and sometimes has become deformed or misshapen.

When non-operative treatment such as physiotherapy, painkillers and anti-inflammatory medications have failed to control the symptoms.

Marcus Green

Knee replacements are generally reserved for patients with "worn out" knees who are in pain.

The causes of this can vary greatly from injury (trauma) to inflammation (like rheumatoid arthritis).

Surgery is required to relieve pain and improve function in those patients who have lost function because of the disease in the knee.

The age of patient can vary dramatically from young active (apart from the knee) to extremely elderly patients in vulnerable positions who need surgery to maintain their independence.

What are the 5 key stages in getting total knee replacement surgery?

Matthew Bartlett

Knee replacement is a complex procedure so it is not terribly helpful to simplify it too much.

I'm not sure about whether there are actually 3 or 5 or maybe 20 key stages in the operation.

In very general terms I look to cause the minimum of damage to soft tissues during the approach, to resect a minimum of bone whilst correcting any deformity of the joint and placing the components accurately.

All excess bone that has formed around the joint needs to be removed and the ligaments around the knee released as necessary to make sure that the main joint and kneecap move well and are stable.

The components are then securely cemented in position and the quadriceps tendon and skin accurately and securely repaired with stitches.

Abdel Hassan

Preoperative preparation and education (e.g. dietary advice/weight loss/exercises).
Preoperative assessment for fitness for surgery and investigations (screening swabs, bloods and X-rays).
The inpatient care pathway and surgery.
Early rehabilitation and healing.
Maturation of healing.

Marcus Green

Keep as fit as possible prior to the operation. Although the joint may be worn out it is still possible to keep exercising and keep muscle bulk good. If the patient is admitted in good shape the operation and the postoperative recovery is easier and potentially quicker.
Good preoperative counselling highlighting the risks and benefits and setting realistic goals.
Access a surgeon who is performing regular knee replacements - studies suggest that the more you do the better you become as a surgeon.
Be exceedingly diligent with postoperative physiotherapy to regain movement and strength.
If in pain take pain relief and ice the knee to enable good and effective physio to take place.

What are the risks involved?

Matthew Bartlett

The major risks are fortunately very uncommon.

Infection worries us most as this can mean having to take the replacement out temporarily in the worst cases.

It is, however a very rare complication (much less than 1%) and we take great care with antibiotics, clean air theatres and spacesuits as well as careful wound care to minimise this.

Less unusual (but still uncommon) risks include DVT and significant stiffness (usually due to excessive bleeding in the joint).

Dislocation after knee replacement is exceptionally rare as is leg length discrepancy (the leg will be restored to its original length as it is put back into a normal straight alignment).

Abdel Hassan

Risks actively managed include: infection, bleeding and thrombosis.

Surgery is conducted with strict techniques, modern equipment and a special environment dedicated to limit infection risks.

Intraoperative bleeding is usually limited by a cuff round the thigh or tourniquet and sometimes medications.

Blood thinning injections or tablets are combined with rapid mobilisation techniques to limit the risk of clots to the legs (deep vein thrombosis) or lungs (pulmonary embolus).

Marcus Green

There are the general risks of having any operation.

Adverse events such as heart attacks and other similar complications are actually quite rare.

Specific risks include infection (approximately 1 in 200), stiffness, deep vein thrombosis, pulmonary emboli and the knee prosthesis coming loose earlier than planned.

Problems with the anaesthetic are also recognised.

Infection is the most feared of these complications as it may lead to the knee replacement becoming loose at a much earlier stage than planned.

In the worse case the whole knee may require removing and replacing once the infection has been cured.

What is recovery from this surgery like? How much time do patients need to take off work?

Matthew Bartlett

Recovery from knee replacement is difficult and prolonged with about 2 months off work (this can be longer or shorter depending on the physicality of one's work, commutes etc.).

Although we do everything that we can with nerve blocks and painkillers (and some people have a relatively easy time postoperatively) it is not helpful to pretend otherwise as this simply causes a lot of anxiety when the postoperative experience does not measure up to expectations.

Most people are able to get out of hospital within a week but the knee has to be kept bending to prevent stiffness, this stretches the scar and causes pain.

Although generally by about 2 months most people's knees feel much better than they did before the operation their knees can continue to improve for a year or more afterwards.

Abdel Hassan

Patients are encouraged to mobilise quickly by adopting enhanced recovery techniques.

Typically patients may be stood on the same day, walking the next and manage stairs on the second or third day.

Regular painkillers are prescribed. Patients on average are off work for approximately six weeks, but this can differ significantly depending on the nature of their work.

Marcus Green

The hospital stay should be between 3 to 5 days.

Avoid driving a car 2 to 6 weeks though if it is the left knee that is replaced driving can start pretty much immediately.

Work recommencing between three to twelve weeks depending on the physical nature of the job.

Even the most motivated patient may find that his recovery is considerably longer than he would have anticipated.

At the time of discharge the patient should be able to bend his knee to a right angle, be independently mobile with crutches and safe to be discharged.

Are there any alternatives to this surgery?

Matthew Bartlett

Yes and surgery should not be rushed into - it is rare that delay will cause any problems with replacing the knee in the future and if we think this might be the case the knee can be monitored with X-rays in clinic.

Painkillers, physio, activity modification, weight loss and use of a stick are among the interventions worth trying.

Abdel Hassan

Yes. These non-operative approaches have less risk, but are not as effective as surgery.

Weight loss, exercise, footwear modifications or orthotics to modify the forces passing through the knee, knee braces and injections are just some options.

Marcus Green

4 key points to avoid surgery are lose weight, do regular exercise to maintain muscle strength, take regular pain relief and try steroid injections to relieve symptoms.

How long does a knee replacement last? Will it need to be replaced?

Matthew Bartlett

How long replacements last is expressed in terms of survival rather than average lifespan.

This seems a little strange at first sight but as many people will have a knee replacement that lasts the rest of their life it is impossible to say how long that replacement would have gone on if they had lived forever.

The 10 year survival rate for a good modern knee replacement is in the order of 97%.

If knee replacements wear out they can be replaced - this is a more complicated operation and although it can be redone many times it does become more difficult each time.

Abdel Hassan

On average, knee replacements last 10-15 years.

Younger patients may thus require more than one joint replacement in their lifetime.

However, being made of modern materials, the longevity is related to how the joint is treated and the quality of the bone to which it is fixed.

Marcus Green

A knee replacement should have a roughly 97% chance of lasting 15 years in the over 60's.

The life expectancy (of the knee replacement) does diminish as the knee replacement is put into a young and more active population.

If a patient undergoes knee replacement surgery between 50 and 55 then the knee may need revising (i.e. redoing) as early as ten years after the initial surgery.

What do you believe are the primary benefits to getting this surgery?

Matthew Bartlett

Relief of pain and restoration of function.

Abdel Hassan

Joint replacement can transform the lives of patients.

It can eradicate severe deformity and 80-90 percent of patients’ pain.

This can lead to significant improvements in the quality of patients’ lives and help them maintain their independence.

Marcus Green

The major aim should be pain relief - secondarily gains such as function, correction of deformity and mobility are also seen.

Some patients worry that they can't afford private treatment. What advice do you have for them?

Matthew Bartlett

It's worth finding out how much it would actually cost before making a decision.

Most consultants and private hospitals will be happy to give an estimate of the costs involved.

Abdel Hassan

Most private hospitals offer competitive fixed cost packages for patients.

In addition, some offer finance options.

Marcus Green

The NHS is slower but practises orthopaedics to an extremely high standard, do your research on who to be referred to and be insistent on referral to the right surgeon, even if it takes a little longer to see the correct surgeon it is worth waiting for to get excellent final results.

What inspired you to specialise in orthopaedic surgery?

Matthew Bartlett

I had a taste of orthopaedic surgery very early in my career and thoroughly enjoyed it.

So much of medicine is about delivering bad news to people that it was very heartening to find a speciality where most of the time we could improve or remove people's symptoms.

Abdel Hassan

I have always been fascinated by the musculoskeletal systems, mechanics and material science.

Orthopaedics combines all these disciplines and provides immediate and dramatic benefits to patients.

I've been fortunate to work with truly inspiring mentors.

As an Orthopaedic Knee Specialist, you are in no doubt that you have made a big difference in patients’ lives and this is very addictive!

Marcus Green

The ability to treat people to get them back to good function and being able to cure disability inspired me.

As a medical student I was a particularly keen sportsman and whereas in many medical specialities that I saw patients were either given chronic prognoses or life limiting diagnoses - in orthopaedics we seemed to restore people to excellent function.

I was also inspired by the consultants that I met in orthopaedics. They all seemed to be having a great time in life and thoroughly enjoying their career.

What is your greatest career achievement to date?

Matthew Bartlett

One shouldn't rest on one's laurels, there's always more to do.

Abdel Hassan

I have been fortunate to receive prizes, scholarships, honours and distinctions.

I've contributed to my speciality at a basic science, clinical and industry level.

In addition, I am involved in teaching trainee surgeons and consultants.

However, my greatest achievement is the appreciation of the importance of the doctor patient relationship and to focus my efforts to providing personalised care for each and every one of my patients.

Marcus Green

Developing working practises which are extremely efficient allowing high quality joint replacement surgery in large numbers.

Particularly in the NHS where there is considerable waste I have been part of a team that really works extremely hard, minimises inefficiency and maximises throughput in both clinics and theatres.