Unicompartmental Knee Replacement (UKR)
What is a unicompartmental knee replacement?
Your knee is composed of three compartments:
- Medial - the inside part of your knee
- Lateral - the outside part of your knee
- Patellofemoral - the front of your knee between your kneecap and thighbone
Over time, the surfaces on the knee joint can start to wear. This can be caused by arthritis or a previous injury to the knee. Arthritis is painful as joints become stiff and inflamed when the smooth lining between the joints gets damaged or wears away. Without the protection of this lining, the rough surfaces of your bones rub together as you move, causing the pain that is all too common to sufferers.
If your knee is damaged in only one compartment you may be a candidate for unicompartmental knee replacement. Your surgeon only replace the damaged compartment with metal or plastic components.
The day of your surgery
At the hospital, we’ll show you to your room where one of our Healthcare Team will meet you to explain each stage of your treatment and recovery. They’ll take notes on your general health, medical and surgical history and ask if you have any allergies. Your blood pressure, pulse and temperature will be taken and an identification band with your name and hospital number on it will be placed on your wrist.
You will be shown where the alcohol hand rub is and how you and your visitors should use it. You will also see staff members using this before they treat you; please feel free to ask us if we have washed our hands. Don’t forget to wash your hands with soap after going to the toilet.
Your consultant will come to see you. And if you haven’t signed a consent form already, you’ll be asked to sign one by your consultant. This is to confirm that you understand the details of your operation, the benefits and the risks associated with it, both during and after your operation.
When it’s time to go to the operating theatre, our ward staff will take you. There, our theatre staff will take you to the anaesthetic room. If you are concerned about anything, please ask. We understand this can be a very stressful time.
What happens during unicompartmental knee replacement?
Unicompartmental knee replacement surgery usually takes between one and a half to two hours. The operation can be performed under general anaesthetic or spinal anaesthetic with sedation. Be sure and discuss your anaesthesia with the Anaesthetist before your surgery.
Your surgeon will make an incision (cut) in the front of your knee. They will examine all three compartments of your knee to confirm the damaged area. The damaged area will be removed and replaced by metal caps or covers. The caps will be held in place by cement. A plastic insert will be placed between the two caps to allow for smooth movement. They will close the incision with staples or stitches.
After the operation
Once your operation is over, you’ll be taken to the recovery room where you will wake from the anaesthetic. Your wound, blood pressure and pulse will be checked carefully. You will have a large dressing covering your wound. You may have a small tube coming out of your wound - this is to drain away any excess fluid from the inside of the wound.
You may also have a drip (infusion) going into your arm. This will keep you hydrated until you are able to drink, and can also be used to give you pain relief. When you are stable and comfortable, a nurse will take you back to your room.
Getting up for the first time
We understand that you may be anxious or worried about getting up, but we will do all we can to help and reassure you. Don’t worry, a member of our Healthcare Team will be there to help you, whenever you are ready. The reason for getting you moving is to improve your circulation and avoid stiffness.
You may be feeling tender and sore, but you can get pain relief medication to deal with any discomfort – just ask one of the nurses if you have any pain. Once out of bed, you will continue to wear support stockings to help your circulation. The physiotherapists will work with you during your stay to help give you the best start with your new joint.
Going home after unicompartmental knee placement
Because unicompartmental knee replacement is less invasive than total knee replacement patients usually go home sooner and return to normal activities earlier. You may stay in hospital one to three days. Before discharge you will have an X-ray of your new knee to check its position.
A physiotherapist will give you some exercises to help get your new knee moving. These are important to help you make a good recovery. The therapist will also show you how to walk up and down stairs and make sure you are confident at doing this before you go home. You won’t be able to drive, so you will need someone to come and take you home from the hospital.
When you go home, you may need some help with shopping and household chores. It’s a good idea to arrange for someone to stay with you - or at least look in on you daily for at least a week.
It’s usual to return to see your consultant as an outpatient after your operation. You may also need to have stitches removed. You’ll be given information about these appointments before you go home. We’ll also give you some pain relief medication to take with you.
When you get home you will be tired for several weeks and should rest. However, it’s also important to aim to gradually increase your physical activity each day, so you should continue with the exercises the physiotherapist showed you. These will help to reduce stiffness and strengthen your legs. You will need to keep using crutches or a walking stick for a while. To help you manage and increase mobility it’s recommended that you take any pain relief medication we have prescribed. Continue taking this until you are pain free.
So you don’t damage your new knee and to help your wound heal, you should:
- Use the shower instead of the bath
- Keep wearing your support stockings - you may have to do so for four to six weeks
Getting back to normal
Everyone heals differently. You will continue to improve over the next six to eight months. Your scar should fade to a thin white line.
Depending on what type of job you do, you should be able to return to work within eight to twelve weeks. You may want to think about a phased return to work.
After your followup visit with your surgeon you should be released to drive but only if you can comfortably operate the pedals and control your car in all situations. This includes an emergency stop. If you are in any doubt about your insurance cover, it’s best to contact your insurance company.
Most people make a good recovery and return to normal activities following unicompartmental knee replacement. As with any surgery there can be complications:
- Infection of the surgical site (incision)
- Blood clots (DVT - deep vein thrombosis)
- Difficulty passing urine
- Chest infection
- Heart attack
Risks specific to unicompartmental knee replacement surgery are:
- Nerve damage
- Damage to blood vessels
- Bearing dislocation
- Infection in the knee
- Loosening of the components
- Severe pain, stiffness and loss of use of the knee (complex regional pain syndrome)
This treatment qualifies for Nuffield Health Recovery Plus Programme - this is free-of-charge optional enhanced recovery programme that enables you to continue your rehabilitation at a Nuffield Health Gym, with the help of a qualified physiotherapist.
Why not print this treatment page so you can discuss any concerns you have with your surgeon?
Feel free to call us about unicompartmental knee replacement on 0845 603 4346 or simply fill in a form to your right and we can call you back.
Unicompartmental Knee Replacement (UKR) can be performed at the following locations:open
Your enhanced recovery programme
Recovery Plus is Nuffield Health's flagship recovery programme available free of charge to our private patients at Nuffield Health hospitals. It is an optional enhanced recovery pathway that starts after you have finished your post-operative physiotherapy, and enables you to continue your recovery at a Nuffield Health Fitness & Wellbeing Centre, at no extra cost.