A knee replacement is an operation for serious arthritis of the knee. To understand your partial, also known as unicompartmental, knee replacement you should first understand a little about the structure of the knee joint.
The knee joint is a hinge joint between the thigh bone (the femur) and the shin bone (the tibia). It also incorporates the kneecap joint (the patella).
Between these three bones the knee bends like a hinge but also rotates slightly to allow greater flexibility. Where the thighbone and shinbones meet, they are covered by a slippery material called cartilage. This allows the knee to glide easily when bending. The whole knee is held together with ligaments.
Arthritis damages the surfaces where the three parts of your knee slide over each other. The worn cartilage no longer serves as a cushion and the damaged bones rub together, they become rough, with a surface like sandpaper. This hurts, and stops your knee bending the way it should. It also makes your knee weak and sometimes bends it out of shape.
For many patients, only one of the areas of your knee has significantly worn away. This means it is possible to replace just the worn part of the knee and leave the remaining healthy cartilage alone.
It important that, despite the discomfort in your knee, you remain as mobile and active as possible. This will maintain your muscle strength and improve the speed and quality of your recovery from the surgery. If you smoke, then this is an ideal opportunity to consider giving up. Smoking increases a number of potential complications following surgery and to gain the full benefit you should stop at least 6 weeks before your surgery.
+ What can I expect pre Knee Replacement Surgery?
You will undergo a number of tests and x-rays and you will receive a clinical examination and have a consultation with me. I will make sure you understand the procedure its alternatives, benefits and most importantly any potential pitfalls or complications. You will then be asked to sign the Consent form. This is a document stating you understand what is involved and want to proceed with the surgery. You will receive a copy of this document.
You will be asked not to eat or drink anything for 6 hours prior to your surgery.
+ What type of anaesthesia is used in my Knee Replacement Surgery?
Most of our knee replacement patients receive spinal anaesthesia however, general anaesthesia is also used in certain patients. Your anaesthetist will discuss the type of anaesthesia used with you prior to surgery.
With spinal anaesthesia, the method we strongly recommend, a narrow catheter is placed between two bones of your spine. A controlled flow of anaesthetic goes through the narrow catheter, anaesthetising your body from the abdomen down so you will not feel anything during surgery. If you do not want to be awake during the surgery, you can, and most people also want, a sedative so that you are completely unaware of proceedings.
If you are undergoing general anaesthesia, you will first be put to sleep by intravenous medication. A mask or a breathing tube then gives an anaesthetic gas to keep you asleep.
+ What is involved in my Knee Replacement Surgery?
A unicompartmental knee replacement is a big operation. It generally takes 1 to 2 hours. I will make a 3-4 inch incision over the front of your knee and remove the damaged / arthritic ends of the thighbone and shinbone. I will then replace these with a metal knee that has a polyethylene bearing to allow low friction between the components. I will only replace the damaged areas of bone, either between the shin and thigh bone (a traditional unicompartmental knee replacement) or between the kneecap and thigh bone (a patellofemoral replacement). The components are held in place by a medical glue we call cement.
Explain to your relatives / friends that you will be away form the ward for up to 4 hours. The theatre schedule is flexible and no specific time can be given to you as to when in the day your surgery will occur. After surgery is completed you will be moved to the recovery area in the operating department for a short time. You will then be transferred to your ward bed where your relatives and friends will be allowed to be with you.
+ Is there much pain with Knee Replacement Surgery?
Normally following your surgery you will experience a little pain. If following the surgery you are experiencing severe pain, please inform the nurse. The nurse will notify the Doctor who will then make an assessment and provide you with appropriate pain medication. We aim to keep your pain scores below 4 out of 10.
+ What is the recovery like after Knee Replacement Surgery?
+ What rehab can I expect after Knee Replacement Surgery?
Your participation in physical therapy is essential to the success of your surgery. The more committed and enthusiastic you are, the quicker your improvement and recovery will be. You will receive extensive physiotherapy during your stay in the hospital, and we will make sure you are safe and mobile prior to your discharge. A physiotherapist will visit you on the day after surgery and will start to instruct you on the exercise program. You will receive physiotherapy each day following the surgery and we strongly encourage you to achieve three goals before discharge.
Be able to lift your leg straight off your bed
Achieve a full straightening of the leg
Be able to bend the knee to at least 70 – 90 degrees
The physiotherapist will guide you through your recovery. Please take note of the ward staff and physiotherapists advice when you commence your mobilisation for the first time. These sessions are normally one on one with a physiotherapist but I would encourage you to practice and continue your exercises in between visits. If it is deemed necessary for you to have outpatient physiotherapy, this will be organized prior to your discharge home.
+ Do I need this operation?
Your participation in physical therapy is essential to the success of your surgery. The more committed and enthusiastic you are, the quicker your improvement and recovery will be. You will receive extensive physiotherapy during your stay in the hospital, and we will make sure you are safe and mobile prior to your discharge. A physiotherapist will visit you on the day after surgery and will start to instruct you on the exercise program. You will receive physiotherapy each day following the surgery and we strongly encourage you to achieve three goals before discharge.
Be able to lift your leg straight off your bed
Achieve a full straightening of the leg
Be able to bend the knee to at least 70 – 90 degrees
The physiotherapist will guide you through your recovery. Please take note of the ward staff and physiotherapists advice when you commence your mobilisation for the first time. These sessions are normally one on one with a physiotherapist but I would encourage you to practice and continue your exercises in between visits. If it is deemed necessary for you to have outpatient physiotherapy, this will be organized prior to your discharge home.
+ Why don’t I just have a total knee replacement?
Until 10 years ago this would have been the traditional choice of surgery. Developments in material science and our understanding of knee arthritis and normal knee motion have allowed the development of partial knee replacements. The outcomes from unicompartmental knee replacements are superior in terms of the function of the knee and they appear to have a longer life span than a traditional total knee replacement. An added advantage is that, should your unicompartmental knee replacement wear out and need re-doing, the operation to convert it to a total knee replacement is simpler and more successful than re-doing a worn out total knee replacement.
+ What are the benefits of Partial Knee Replacement?
Knee replacement surgery is continually evolving however is very successful in treating the pain of arthritis. It is important to notes that although successful at eliminating your pain, it is not an operation to give you back a ‘normal’ knee. The main aim is to provide a painless knee with adequate movement for the majority of daily activities. Success of knee replacement surgery depends upon many factors of which rehabilitation is of utmost importance. The most perfectly performed surgery can be quickly undone by inappropriate or unsupervised rehabilitation, particularly in the early stages following surgery.
+ What are the potential complications of Partial Knee Replacement?
These are uncommon, but do occur occasionally
If you have questions about your surgery please ask one of my team at the pre-assessment clinic or once admitted for surgery. If you have questions about your rehabilitation please contact your physiotherapist.
If you have any problems, especially if you experience any excessive skin redness, persistent wound discharge, excessive swelling, or severe pain during or after exercise, call Mr Houlihan-Burne’s secretary.
Call your GP if you develop calf pain and tightness, shortness of breath, or if you develop a fever and feel unwell.
17 Fitzhardinge Street
Marylebone
London
W1H 6EQ
Rickmansworth Rd
Northwood
Middx
HA6 2JW
BMI The Chiltern Hospital
London Road
Great Missenden
HP16 0EN
One Medical House
Boundary Way
Hemel Hempstead Industrial Estate
Hemel Hempstead
HP2 7YU
