Partial Knee
Replacement

Overview

This surgical procedure is used to treat arthritis that is confined to one area of the knee. The aim is to replace the part of the knee that is painful, stiff and often deformed with one that is pain-free, mobile and correctly aligned.

In this procedure only the most damaged areas of the knee are removed and replaced.

This is a less invasive procedure than a total knee replacement and those who are candidates benefit from:

• Smaller incision
• Smaller amount of bone removal
• Less complications
• Faster recovery period
• Better function

Partial versus Total Knee Replacement

The operation

1. This is usually done under general anaesthetic.
2. This operation takes approximately 60 mins.
3. A cut is made over the front of your knee.
4. The diseased sections of bone are removed and implants (prosthesis) are fitted over the bone.
5. The joint is then tested to make sure everything fits well and is aligned.
6. The wound is then closed using stitches and covered using a large dressing.

After the operation

• Pain relief – good pain relief is important and you will be given this during your procedure. Some people need more than others so please ask for help if you are in any discomfort following your procedure.
• Hospital stay is usually 1-2 days.
• Physical activities – you will be encouraged to walk immediately on your knee usually on the same day or following morning. Most patients undergoing this surgery will be walking independently and without aids within 6 weeks.
• Swelling and bruising may take up to 8-12 weeks to improve.
• Showering and bathing – you need to keep your wound well covered using the waterproof dressing provided whilst showering. When bathing do not submerse your knee in water as dressing are not designed to withstand this. This is important for the first 2 weeks following your surgery.
• Do not remain in one position for too long whilst in bed to prevent sores on your back, heels and ankles.
• Increase activity with each day. You will notice most improvement in the first 3 months but can expect further improvement for up to 12 months following surgery as your muscles become stronger.

Your surgeon and physiotherapist will discuss with you issues surrounding:

• Returning to work
• Using your knee following your operation
• Driving
• Anticipated length of rehabilitation

Possible complications

All surgery has associated risks. These risks are higher in some patients than others. Risks include:

• Anaesthetic – your anaesthetist will discuss risks associated with the anaesthetic with you.
• Infection – there is a very small risk of wound infection following your operation that is minimised by giving you antibiotics. If at any time you notice a fever or increased pain, swelling or redness around your wound, please contact us urgently. Rarely patients may suffer from deep infection of the knee replacement that may necessitate a return to theatre for further surgery and/or be treated with a course of antibiotics.
• Nerve or blood vessel damage – this can sometimes occur after surgery and if severe may require a return to theatre.
• Deep vein thrombosis – this is a blood clot in the leg. You will be given blood thinning medication and support stockings to help prevent this. If you notice discomfort in your calf then please seek immediate medical attention.
• Pulmonary embolism – this is a blood clot in your lungs. You will be given blood thinning medication to help prevent this. If you notice a sharp pain in your chest or shortness of breath then please seek immediate medical attention.
• Loosening – your new knee may become loose with time or eventually wear out. This will need to be replaced depending on your level of symptoms.
• Numbness – there is typically numbness on the outer side of the knee. This is because some small skin nerves are cut during the operation. Some but not all of this sensation should return. Numbness should not stop you from kneeling.
• Revision risk – the risk of the need for a revision (where the partial knee replacement is revised to a total knee replacement) is higher overall when compared to the revision rate of total knee replacements however is balanced against the benefits of partial knee replacements (highlighted above).

Please notify healthcare professionals of your artificial joint when undergoing operations, hospital examinations, dental work or if you have a systemic infection. They might wish to give you antibiotics to prevent infection occurring in your artificial joint.