Total Knee Replacement vs Partial Knee Replacement: Which Is Right for You?

Knee pain can make everyday activities – walking, climbing stairs, even sleeping – feel like hard work. If your symptoms are not improving with simple measures, you might be wondering whether you need a total knee replacement or a partial knee replacement.

There is no one-size-fits-all answer. The right option depends on:

• how severe your pain is
• how much of the knee joint is damaged
• your age, general health, and activity level

Most importantly, the decision should always be made together with a qualified orthopaedic specialist who can assess your individual situation.

This guide explains:

• what knee replacement surgery is
• the difference between total and partial knee replacement
• key pros and cons of each approach
• how newer options such as Arthrosamid® injections may help some people

It is designed to help you ask better questions and feel more informed – not to replace professional medical advice.

What is a knee replacement?

A knee replacement is an operation in which the damaged surfaces of the knee joint are removed and replaced with an artificial joint (also called an implant or prosthesis), usually made of metal and high-grade plastic.

The main aims of knee replacement surgery are to:

• reduce pain
• improve movement and function
• help you return to normal daily activities and improve quality of life

Knee replacement is most commonly performed for severe osteoarthritis, but it may also be used when the joint has been damaged by:

• previous injury (post-traumatic arthritis)
• inflammatory conditions such as rheumatoid arthritis
• long-term wear and tear that has not responded to other treatments

Surgery is usually considered only after non-surgical options have been tried, such as:

• physiotherapy and exercise
• pain-relieving or anti-inflammatory medicines
• weight management
• joint injections

If these measures no longer control your pain or your knee is badly worn, your specialist may discuss knee replacement surgery with you.

What is a total knee replacement?

In a total knee replacement (TKR), the surgeon resurfaces all of the main parts of the knee joint:

• the end of the thigh bone (femur)
• the top of the shin bone (tibia)
• sometimes the underside of the kneecap (patella)

These surfaces are replaced with artificial components. A smooth plastic insert sits between the metal parts to allow the joint to bend and straighten more comfortably.

Total knee replacement is usually recommended when:

• damage to the knee is more extensive, affecting more than one part (compartment) of the joint
• you have severe, constant pain that affects sleep and day-to-day life
• X-rays show advanced arthritis throughout the knee

Common features of total knee replacement include:

• usually done through a larger incision
• more bone and cartilage are replaced
• recovery and rehabilitation may take a little longer than with a partial replacement
• because the whole joint is resurfaced, there is often a lower chance of needing further surgery in the long term than with a partial knee replacement, especially if arthritis would otherwise spread to other parts of the knee

For many people, total knee replacement offers long-lasting pain relief and a significant improvement in function.

What is a partial knee replacement?

A partial knee replacement (PKR) – sometimes called a unicompartmental knee replacement – involves replacing only the damaged part of the knee, rather than the entire joint.

Many people have arthritis that affects just one side or one area of the knee. If the rest of the joint and the surrounding ligaments are in good condition, a partial replacement may be an option.

During partial knee replacement:

• the surgeon removes only the worn-out cartilage and bone from the affected area
• an artificial component is fitted into that specific part of the knee
• the healthy parts of the joint, including the ligaments, are left intact

Typical features of partial knee replacement include:

• usually performed through a smaller incision
• less bone is removed, and the operation is generally less invasive than a total replacement
• many people experience less pain immediately after surgery and a shorter initial recovery period
• the knee may feel more “natural” because more of your own joint is preserved

However, partial knee replacement is only suitable when damage is limited to one specific area. If arthritis develops later in another part of the knee, further surgery – sometimes a conversion to a total knee replacement – may be needed.

Total knee replacement vs partial knee replacement: key differences

Although both operations aim to relieve pain and improve function, there are some important differences between total and partial knee replacement.

1. Extent of joint damage

• Total knee replacement – usually chosen when arthritis affects several parts of the knee.
• Partial knee replacement – considered when arthritis is limited to a single compartment and the rest of the joint is healthy.

2. Surgical approach and recovery

• Total – a larger operation with more bone surfaces replaced. Recovery often takes longer, and rehabilitation exercises are essential.
• Partial – smaller incision and less disruption to the joint. Many people find early recovery quicker, with less post-operative pain.

3. How the knee feels afterwards

• Total – can feel very stable and reliable, but may feel slightly less “natural” as the whole joint has been resurfaced.
• Partial – often feels more like your original knee because more of your own bone and ligaments remain.

4. Long-term outlook and further surgery

• Total – because the entire joint is replaced, there may be a lower long-term risk of needing further surgery due to arthritis spreading elsewhere in the knee.
• Partial – if arthritis progresses to other compartments, some people later require a revision operation or conversion to a total knee replacement.

5. Who is suitable?

Your suitability depends on many factors, including:

• age and activity level
• pattern and severity of arthritis on X-rays or scans
• knee stability and ligament condition
• overall health and medical history

An experienced orthopaedic surgeon will take all of these into account before recommending one option over the other.

How do you know which type of knee replacement is right for you?

The choice between a total and partial knee replacement is highly individual. In general:

• Total knee replacement may be necessary if:
• • pain is severe and constant
  • the knee is badly worn or deformed
  • several parts of the joint are damaged beyond repair
• Partial knee replacement may be an option if:
• • arthritis or damage is limited to one area
  • the ligaments are strong and stable
  • you have good range of movement in the knee

Your specialist will usually:

• take a detailed history of your symptoms
• examine your knee for movement, alignment and stability
• review X-rays and sometimes other scans
• discuss your lifestyle, work, hobbies and goals

Together, you can weigh up the benefits and risks of each procedure and decide what best matches your priorities.

Non-surgical and newer options: Arthrosamid® injections

Joint replacement is not the only way to treat knee pain. Many people can successfully manage symptoms or delay surgery with:

• tailored physiotherapy and strengthening exercises
• weight management to reduce stress on the joint
• pain-relieving or anti-inflammatory medicines (when appropriate)
• injection therapies

At our clinic, our team of expert arthritis specialists also offers Arthrosamid®, a newer injection treatment for certain types of knee osteoarthritis and knee injuries.

Arthrosamid® involves injecting a soft, gel-like material into the knee joint. The aim is to:

• cushion and support the joint
• reduce pain gradually over time
• improve day-to-day comfort and function

For some people, this type of treatment may help delay or reduce the need for knee replacement surgery, although it is not suitable for everyone and results can vary.

If you would like to discuss whether Arthrosamid® might be appropriate for you, or you would like more detail about the Arthrosamid® cost and treatment process, please get in touch with our specialist team.

The bottom line

Both total knee replacement and partial knee replacement can be highly effective treatments for painful, arthritic knees. In simple terms:

• total knee replacement is often better when the whole joint is badly affected
• partial knee replacement may be suitable when damage is confined to one area and the rest of the joint is healthy

Whichever option you are considering, a face-to-face assessment with a qualified orthopaedic professional is essential. They can guide you through your choices, explain the risks and benefits, and help you find the treatment plan – surgical or non-surgical – that is safest and most appropriate for you.