Orthopaedic Surgeon
specialising in Hip and Knee
Replacements

TOTAL KNEE REPLACEMENT (TKR)

TKR involves replacing the worn parts of the knee joint with an artificial one. The artificial joint is made of metal and polyethylene (plastic). They are fixed onto the thigh (femur) and leg (tibia) bones using bone cement.

Your suitability for a TKR will be determined as a joint decision with your surgeon. This will depend on your symptoms, findings on examination and expectations from treatment. An X-ray examination is an essential part of this decision process.

The results of total knee replacement are generally excellent. People who undergo the procedure have significant pain relief and restoration of physical function. Patients are usually admitted to hospital on the day of surgery and on average stay for 2 days in hospital. All necessary pre-operative investigations (blood tests, ECG and x-rays) are carried out in the weeks preceding the procedure in a special PRE-ASSESSMENT clinic by specialist nurses.

The Anaesthetic

Total knee replacement is carried out under anaesthesia. This may involve either a general anaesthetic (where you are asleep) or a regional anaesthetic (injection into the back- epidural or spinal). You will have a chance to discuss your suitability to one of these methods and choice with the anaesthetist on the day of surgery.

Most patients find regional anaesthesia a scary prospect before but are very satisfied with it after the event.

The Operation

The operation is made of several steps which are outlined below.

·       EXPOSURE

o   You will have a cut on the front of your knee extending from just below you knee cap to just above. This allows your surgeon to gain access to the bones making up the knee joint.

·       BONE PREPARATION

o   The corresponding surfaces of the thigh bone (femur) and leg bone (tibia) are shaped to allow the total knee implants to be inserted.

·       BALANCING

o   This is the step where the surgeon makes fine adjustments to the ligaments and other soft tissues around the knee to ensure that it will be stable and move adequate amounts.

·       IMPLANTATION

o   The implants are cemented onto the previously prepared bone surfaces.

·       CLOSURE

o   The wound on the front of the knee is closed using sutures under the surface of the skin. There will not be any stitches to take out after the wound has healed.

Early Post-Operative Period

Following surgery, you will return to the ward. Most people do not require extra pain relief in the early hours. This is because your knee will be injected with local anaesthetics during surgery. Most patients are able to get up and take some steps within hours of the operation.

During this period, you are encouraged to move your foot and lift your leg off the bed. You are also able to bend the knee as much as you are able to.

On the day after your surgery you will be seen by the physiotherapists. They will show you how to walk safely using supports and the exercises you have to do when you are sitting or lying down. You will also have an X-Ray examination of your knee.

Over the next few days you will be progressively more mobile and will be able to go home whenever you are able to walk up and down stairs. This usually takes 2 or 3 days.

After Discharge

You do not routinely need physiotherapy after discharge. However, if it is felt that you may benefit from this an appointment will be made before you go home. You will be given a sheet of instructions to follow at home. It is important that you continue exercising at home as this will ensure the best result from your operation.

It takes about 6 weeks for you to notice a big improvement in your knee. This is when we remove all restrictions with regards your activities. You should be able to drive after 4-6 weeks. After about 3 months you will be able to do most things. Overall, it takes 1 year for you to reach maximum recovery.

Follow-up

Your first routine follow-up appointment will be at 3 months. This is to ensure that your wound has healed up and that you are progressing with your mobilisation.

You will have a second appointment at 1 year following surgery. You will have an x-ray of your knee at this stage.