Total knee replacement, also called knee replacement surgery, is an operation used to relieve pain and improve function when the knee joint has been severely damaged, most commonly because of arthritis.

During the operation, the damaged surfaces of the knee joint are replaced with artificial components designed to allow the knee to move more smoothly.

Knee replacement can provide significant pain relief and improve walking and everyday activities in appropriately selected patients.

What is total knee replacement?

The knee is made up of the thigh bone (femur), shin bone (tibia) and kneecap (patella). Their surfaces are covered with a smooth layer of cartilage that allows the joint to move easily.

With severe arthritis, this cartilage becomes damaged or worn away. The bones may then rub against each other, causing pain, stiffness and difficulty with movement.

In total knee replacement, the damaged surfaces of the knee are removed and replaced with artificial components. The aim is to relieve pain, restore the alignment of the leg and provide a stable, functioning knee.

Why might I need a knee replacement?

Knee replacement may be considered when arthritis has caused:

• Persistent knee pain

• Increasing stiffness

• Difficulty walking

• Difficulty climbing stairs

• Pain that affects sleep

• Difficulty with work or everyday activities

• Significant limitation of activities you enjoy

Surgery is generally considered when these problems continue despite appropriate non-surgical treatment.

An X-ray showing arthritis does not by itself mean that you need a knee replacement. The decision should take into account your symptoms, examination, X-rays and how much the problem affects your life.

Do I need a knee replacement just because my X-ray shows severe arthritis?

No.

The severity of arthritis on an X-ray and the severity of symptoms do not always match.

If your symptoms are manageable and you can carry out your daily activities comfortably, knee replacement may not be necessary.

Surgery is usually considered when pain and stiffness significantly affect your quality of life and other treatments are no longer providing enough relief.

What are the alternatives to knee replacement?

Depending on the severity of arthritis, treatment may include:

• Exercise and physiotherapy

• Weight management when appropriate

• Activity modification

• Medicines when appropriate

• Injections in selected patients

• Other treatments depending on the cause and pattern of arthritis

The appropriate treatment depends on the condition of your knee and your symptoms.

What happens during total knee replacement?

The operation involves removing the damaged surfaces of the thigh bone (femur) and shin bone (tibia) and replacing them with artificial components.

The damaged surface of the kneecap may also be treated depending on the condition of the joint and the surgeon's assessment.

A plastic component is placed between the metal components to allow smooth movement of the knee.

The aim is to create a knee that is pain-free or substantially less painful, stable and functional.

Is the whole knee replaced?

Despite its name, total knee replacement does not mean that the entire knee is removed.

The operation replaces the damaged joint surfaces while preserving the healthy bone and other structures wherever possible.

The major ligaments and other soft tissues around the knee are assessed during surgery and managed according to the type of knee replacement being performed.

What type of knee replacement is suitable for me?

The choice of knee replacement depends on the condition of your knee, the pattern of arthritis, the condition of the ligaments and your individual requirements.

In most patients with arthritis affecting multiple parts of the knee, total knee replacement is appropriate.

In selected patients whose arthritis is limited mainly to one part of the knee and whose remaining knee structures are healthy, partial knee replacement may be an option.

The decision should be made after assessing your symptoms, examination and X-rays.

What are the benefits of total knee replacement?

The main goal of knee replacement is to relieve the pain caused by arthritis and improve your ability to move and perform everyday activities.

Most patients experience significant improvement in pain and function after surgery. They may find it easier to walk, climb stairs, sleep, exercise and carry out daily activities that had become difficult because of knee arthritis.

For many patients, the greatest benefit is not simply a better knee X-ray, but being able to return to a more active and independent life with much less pain.

How long does a knee replacement last?

Modern knee replacements are designed to provide long-lasting pain relief and good function.

Most patients can expect their knee replacement to function well for many years, and modern implants have excellent long-term results. Many knee replacements continue to function well 15–20 years or longer after surgery.

How long a knee replacement lasts varies between individuals and can be influenced by factors such as activity level, body weight, implant design and other patient-related factors.

With appropriate care and regular follow-up, a knee replacement can provide many years of improved mobility and a better quality of life.

What should I expect after surgery?

Most patients begin moving the knee and walking soon after surgery.

Physiotherapy and regular exercises are an important part of recovery. The early focus is on:

• Controlling pain and swelling

• Regaining knee movement

• Walking safely

• Improving muscle strength

• Gradually returning to normal activities

Recovery continues over several months, although the exact pace varies from person to person.

How much pain will I have after knee replacement?

Some pain and swelling are expected in the early period after surgery, but pain is usually well controlled with modern pain-management methods.

You will be encouraged to start moving your knee and walking soon after surgery. As healing progresses, pain and swelling gradually decrease, while movement and strength improve.

Most patients notice a substantial improvement in their arthritis-related pain as recovery progresses.

The experience is different for every patient, but the aim of modern knee replacement and rehabilitation is to make recovery as comfortable and active as possible.

When can I walk after knee replacement?

Most patients are encouraged to stand and walk with assistance soon after surgery, depending on their overall condition and the surgeon's advice.

You may initially use a walker or other support.

As your strength, balance and confidence improve, you can gradually move towards walking without support.

When can I return to normal activities?

Recovery varies between individuals.

Many patients can gradually return to everyday activities over the first several weeks. Activities such as climbing stairs, driving and returning to work depend on your progress and the type of work you do.

Your surgeon and physiotherapist can guide you based on your recovery.

Can I exercise after knee replacement?

Yes.

Regular physical activity is encouraged after recovery.

Low-impact activities such as:

• Walking

• Cycling

• Swimming

• Golf

• Other suitable recreational activities

can generally be continued.

High-impact activities involving repeated running, jumping or heavy loading of the knee may not be recommended because they can place greater stress on the replacement.

Your activity level should be discussed with your surgeon based on your individual situation.

What are the risks of knee replacement?

Knee replacement is a well-established and commonly performed operation with a high rate of patient satisfaction and good long-term results.

As with any major surgery, complications can occur. These may include:

• Infection

• Blood clots

• Bleeding

• Stiffness

• Persistent pain

• Instability

• Wear or loosening of the implant

• Injury to nerves or blood vessels

• Need for further surgery

Fortunately, serious complications are uncommon, and several measures are taken before, during and after surgery to reduce these risks.

Your surgeon will discuss the risks relevant to your individual health and circumstances before surgery.

Will my knee feel completely normal after replacement?

A knee replacement is designed to relieve pain and restore useful movement and function, rather than to exactly reproduce a natural knee.

Most patients experience a major improvement in pain, walking ability and everyday activities after recovery.

You may notice some clicking, mild stiffness or an awareness of the artificial joint, particularly during certain movements. These sensations do not necessarily mean that anything is wrong with the knee.

The final result depends on several factors, including the condition of your knee before surgery, your muscle strength and your rehabilitation.

What is the success rate of total knee replacement?

Total knee replacement is one of the most successful operations for treating severe knee arthritis.

Most patients experience substantial relief from pain and significant improvement in mobility and everyday activities after surgery.

The majority of patients are able to walk more comfortably, perform daily activities with greater ease and return to many activities that had become difficult because of arthritis.

A successful knee replacement is not simply an improvement on an X-ray. The real goal is to help you live with much less pain and move more comfortably.

When should I consider knee replacement?

There is no fixed age at which a person should have a knee replacement.

The decision is usually based on how much the arthritis is affecting your life, rather than your age alone.

Knee replacement may be appropriate when:

• Knee pain is persistent or severe

• Walking or climbing stairs has become difficult

• Pain is affecting your sleep

• Everyday activities have become increasingly difficult

• You are unable to enjoy activities that were previously important to you

• Non-surgical treatments are no longer providing sufficient relief

• X-rays show significant damage to the knee

If these problems are significantly affecting your quality of life, knee replacement can be an effective way of reducing pain and restoring mobility.

Frequently asked questions

Is knee replacement only for older people?

No.

Although knee replacement is more common in older adults, age alone does not determine whether you are suitable for surgery.

The condition of your knee, severity of symptoms, general health and the effect of arthritis on your daily life are more important considerations.

Can I avoid knee replacement if I have severe arthritis?

Some people with severe arthritis are able to manage their symptoms without surgery for some time.

However, if pain, stiffness and difficulty with daily activities continue despite appropriate treatment, knee replacement may offer the most reliable and lasting improvement.

The decision should be based on how your knee is affecting your life and your expectations from treatment.

Will I be able to bend my knee after replacement?

Yes.

Regaining movement is an important part of recovery after knee replacement.

Most patients are able to bend and straighten the knee sufficiently for normal daily activities, although the final range of movement varies between individuals.

Starting movement early and following the recommended rehabilitation programme can help you achieve the best possible result.

Can both knees be replaced?

Yes.

If both knees have significant arthritis, both knees can be replaced.

Depending on your health, symptoms and individual circumstances, the operations may be performed at the same time or separately.

Your surgeon can discuss which approach is more appropriate for you.

What if I am not ready for surgery?

That is completely reasonable.

Knee replacement is usually an elective operation, so you can discuss your options with your surgeon and decide when the time is right for you.

However, if pain and disability are significantly affecting your quality of life despite non-surgical treatment, there is no need to wait until the knee becomes unbearable before considering surgery.

The right time for knee replacement is when the potential benefits of surgery are meaningful to you and you are ready to proceed.