Partial knee replacement


A less invasive procedure to treat an arthritic joint by replacing only the most damaged portion

What is a unicompartmental knee replacement?

Unicompartmental, or partial, knee replacement surgery is a procedure to treat advanced osteoarthritis affecting just one compartment of the knee joint.

As partial knee replacement involves a smaller incision, it's a preferred alternative to total knee replacement, causing less damage to the bones and resulting in a faster recovery for the patient.

The procedure is being used more in younger patients with arthritis, allowing them to keep more of their knee joint.


Why do I need a partial knee replacement?

Your specialist may recommend partial knee replacement surgery if you have persistent pain which hasn’t responded to other treatments.

One of the most common causes of such pain is osteoarthritis. Your body protects your bones from scraping against each other with connective tissue, also known as articular cartilage. That tissue can wear away over time, leading to inflammation and osteoarthritis.

Sometimes, the arthritis only affects one side of the joint. In these cases, a patient might benefit from a partial knee replacement.

The surgery can also treat other conditions, such as haemophilia, gout, or severe arthritis caused by an injury.

Benefits of partial knee replacement surgery

A partial knee replacement can treat the associated pain and improve mobility significantly.

Other benefits include:

  • Preservation of all healthy bone and ligaments
  • Less invasive surgery
  • Shorter hospital stay
  • Lower risk of complications
  • Less tissue trauma
  • Reduced blood loss
  • Reduced post-operative pain
  • Faster rehabilitation and recovery
  • Improvement in the knee’s range of motion

How much will a partial knee replacement cost me?

The cost of your knee procedure will depend on your diagnosis as recommended by your consultant.  
Costs are made up of:

  • pre-assessment and admission tests
  • hospital accommodation and meals
  • nursing care
  • heatre fees and drugs
  • dressings, removal of stitches and plaster as required
  • Take home prescriptions

Stays in hospital will vary; lengths of stay can vary from 2 to 5 nights.  For those patients looking for certainty and know their costs up front, should enquire about our fixed price partial knee replacement packages.  Your consultant will be able to advise you if your procedure is eligible.  


Need to know

  • What happens during a partial knee replacement? icon plus

    During the procedure, the surgeon resurfaces worn bone and cartilage with metal and plastic implants.

    The surgery is usually performed using small incisions, meaning the patient can heal more quickly than with a total knee replacement.

    Surgery is usually carried out under general anaesthetic, but it can also be performed with a local anaesthetic, such as an epidural. Your consultant will recommend the best approach for you. The operation usually lasts between one and two hours and you may need to spend up to three nights in hospital.

  • How painful is a partial knee replacement? icon plus

    During the surgery itself, you won't experience any pain, as you’ll be under anaesthetic (either general or local as advised by your consultant).

    You’ll be able to walk soon after the procedure, though it’s likely you’ll experience some short-term pain whilst doing so. Your knee might feel a bit stiff, and you may have trouble bending it. Your doctor may prescribe medication to control the pain – usually local anaesthetic and anti-inflammatory medication.

  • Is a partial knee replacement worth it? icon plus

    Whether or not you should have a partial knee replacement depends on the condition of your knee and other criteria, including age and weight.

    If your arthritis only affects one compartment of the knee joint, then partial knee replacement could be beneficial. The advantages are that it preserves the healthy bone and ligaments and, as previously mentioned, involves less surgery, less trauma and usually results in a quicker recovery.

    Not everyone with chronic knee pain can benefit however. A partial knee replacement isn’t usually suitable for patients with rheumatoid (inflammatory) arthritis, as the condition tends to affect the entire joint. Similarly, patients who have had a previous ligament injury may not be suitable for this surgery.

    Your specialist will discuss all your options with you as part of your personalised care plan.

  • How long does a partial knee operation take? icon plus

    Partial knee replacement surgery can take between one and two hours.

    The length of the procedure depends on how much of the joint the surgeon has to replace.

  • How to prepare icon plus

    Before you have the operation, your consultant will explain the procedure to you, and take you through any possible risks and side effects. They’ll be happy to answer any questions you may have about the surgery at this point.

    If you’re having a general anaesthetic, your consultant will also let you know how long you should avoid eating and drinking before your operation.

  • Partial knee replacement recovery icon plus

    Partial knee replacements are less invasive than a total knee replacement, and you can expect to go home within three days.

    A member of our physiotherapy team will visit you after surgery and help you to get moving with the help of crutches or a walker. They’ll also be able to give you advice on appropriate exercises for you to do at home to support your recovery, and how much weight you’ll be able to bear in the early stages. Most patients are able to walk without the aid of crutches or a walker after one to two weeks.

    Your consultant will let you know when you can get back to your usual routine, including work or exercise. Typically this is likely to be six weeks after surgery.

Our knee consultants

We're proud to work with leading orthopaedic experts who specialise in diagnosing and managing problems and conditions of the knee joint, and whose skills are matched by their integrity and compassion.

Our locations

From complex knee surgery to diagnostic tests and procedures, we provide exceptional orthopaedic care across our network of hospitals, outpatient centres and specialist clinics.

Request a knee appointment

We're happy to help you make an appointment with one of our experienced knee consultants. We can also make imaging and outpatient physiotherapy appointments for you.

Call us today

020 7079 4344
This content is intended for general information only and does not replace the need for personal advice from a qualified health professional.
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