Patient Information
Knee Surgery
At Cheltenham Hip Clinic, we treat a wide range of knee conditions. It’s important to note that not all knee problems require surgery and we will always look for a non-surgical solution where possible.
However, should you require surgery, the information below aims to address some of the concerns you may understandably have.
Nowadays, total knee replacements are very successful at relieving pain and restoring mobility. As with all operations, though, there are potential risks associated and it’s important to understand these before undergoing surgery.
Don’t worry, though, all this will be discussed fully with you in person well before your operation and there’s plenty of time to ask any questions you might have.
Anaesthesia
Today’s anaesthetics are very safe. The anaesthetist will talk to you about the type of anaesthetic that is best for you and the risks associated with it. There are also the general risks of surgery, including heart and lung problems, but these are uncommon.
A common way to provide anaesthesia is to give an injection into the base of the spine which makes the legs go to sleep for four to six hours. This is used in conjunction with sedation so you will effectively be asleep during the operation.
Infection
Despite all the precautions taken, there is always a small risk of infection. We do everything we can to reduce the risk of infection at all stages. All patients are screened for MRSA prior to admission to the ward and all patients receive antibiotics just prior to surgery. We also take numerous stringent measures to prevent infection during the operation.
Should an infection occur, a superficial infection can usually be treated with antibiotics. If an infection is around the new knee itself, a further operation would be required to wash out the joint. In a very small number of cases (approx. 1%), a deep infection would require revision of the knee replacement and re-insertion of a new knee when the infection has been cleared.
Stiffness
Often patients have extremely stiff knees before their surgery. It is very unusual, but possible, that some patients will develop a stiff knee after their operation. If this occurs soon after the operation, further manipulation can be used to improve the range of movement.
Tender scar
The scar over the knee can occasionally be tender. It is relatively common to have a numb patch, about the size of a 50p piece, just next to the knee but this does not usually cause any problems.
Occasionally people comment that they have difficulty kneeling after their operation but it often emerges that they have not been able to kneel for several years due to the discomfort.
Neurovascular deficit
There is an important nerve and blood vessel which runs at the back of the knee close to where the surgery is performed. It is extremely unusual for these to be damaged but it is a risk associated with surgery.
Blood clots
We take blood clots extremely seriously. Due to the nature of the operation, patients are at risk of blood clots forming in the veins in the lower legs. A blood clot in the calf veins themselves (known as a deep vein thrombosis) is not usually a problem, although this can be much more serious if the blood clot detaches and moves to the lung (pulmonary embolus).
The rate of occurrence of a pulmonary embolus is quoted at 3 per 1,000 patients, but the real figure is probably actually lower than this as patients are up and about much quicker these days.
We are very proactive about preventing blood clots, and measures include regular testing for blood clot risks and using blood thinning agents.
If patients do develop a blood clot, they are treated with a blood thinning agent called Warfarin.
Wear and loosening
Knee replacements can become loose and wear out with time. If this happens then revision surgery may be necessary.
Mr Mutimer, the surgeon at Cheltenham Hip Clinic, always follows up with patients as per national guidelines for best practice. This includes an X-ray at one, five and ten-year intervals after the knee replacement – these checks help to spot any loosening. Revision surgery can be more difficult than first-time surgery and the results are not as predictable.
Persistent discomfort
Whilst eight out of ten people have an excellent result from knee replacement surgery, there are the occasional patients who get persistent discomfort after their operation. Even after investigation, sometimes no cause for this can be found. Fortunately this is rare.