Knee Replacement FAQ
Does Dr Martin use a prosthesis with good results?
Dr Martin uses well-established knee replacement prostheses with reliable long term results confirmed in the Australian Joint Registry. He has taken extra steps to track his own results by choosing to be identified in the registry. Dr Martin also requests detailed registry reports regarding knee replacements in different situations, and different patients, to minimise the possibility of failure for each patient.
How much physio will I need after the operation?
The recovery after knee replacement surgery is generally much easier than it used to be and Dr Martin is continually fine-tuning his practice to make it as easy as can be. For many people intense physiotherapy is no longer necessary after the joint replacement. This is especially the case for people who have undergone a physiotherapy course prior to the surgery.
Often it is now simply a matter of doing some post-operative exercises, as advised by a physiotherapist, and getting on with life. Some patients will require specific attention to some aspect of their recovery and this is something that is dealt with on a case by case basis.
Can I have both at once?
It is certainly possible to do both knees at once. This is reasonable in a healthy patient in their 70s or younger who has pretty much equally bad knees. The recovery is not much more difficult than one at a time. In general people might stay in hospital 1 day longer. Recently most of Dr Martin’s bilateral total knee replacement patients only needed 2 days in hospital!
Having both done at once is a bigger operation, but for the right patient it is probably about as safe as having one side done and the other some time later on. People are choosing to have two at once more and more frequently as the recovery from the operation gets easier. For people with 2 bad knees it can be an excellent option. Dr Martin performs bilateral total knee replacements very frequently.
Will I need a blood transfusion?
Blood transfusions after knee replacements are exceedingly rare these days. However, it is important to tell your doctor if you have a bleeding problem. It is also important to discuss all your medications, including over the counter medications, and alternative treatments, as some of these have a blood thinning effect. Pre-operative self-to-self blood donation is not offered any more as blood transfusions are so rare that there is no benefit.
What is it like to have an artificial knee?
It is very important to have a realistic idea of what to expect from a knee replacement. For example, 1 in 5 people will have some degree of permanent on-going pain after knee replacement surgery. This should mostly be minor and manageable with simple pain relief. Severe on-going pain is very, very unusual otherwise the surgery would be redundant. Numb patches around the incision are very common. These usually become less noticeable with time, but some permanent numbness usually persists.
Some feelings of clunking or swelling are reasonably common and usually settle with time. About 50% of people cannot comfortably kneel or squat after knee replacement surgery. It is normal for the knee to be swollen and warm for some months after the surgery. An artificial knee isn’t a super knee. It isn’t even as good as the healthy knee of a young person but it is normally much better than a miserable worn-out one.
Will I trigger an alarm at the airport?
This depends a bit on what sort of metal you have implanted and what sensitivity the security staff set their equipment to. People ask if they should carry a card or certificate for the joint replacement, but that wouldn’t make sense because such a document could easily be forged. The airport security staff are used to processing people who have had joint replacement surgery. Enjoy your trip!
What can go wrong after knee replacement?
Serious problems after a knee replacement are very unusual and Dr Martin and his team take every step possible to prevent them. Despite these steps, problems can still occur. For example, infection can cause early failure or on-going pain. A late infection years after the surgery is also possible but also very unusual. The overall risk of failure due to infection is less than 1%. Failure can also occur due to wear, loosening, breakage of the bones about the knee or for other reasons.
Some degree of minor permanent pain is reasonably common after knee replacement. On-going severe pain is very unusual but still possible if something goes wrong. Occasionally the knee might set very stiffly or, conversely, it can be too wobbly. A large part of the surgery is getting this balance right.
Sometimes a the leg might end up bow legged or knock kneed but this is also unusual with modern techniques. It is possible, but exceedingly unusual, to have a serious nerve or blood vessel injury during the surgery. In the very worst case scenario this can result in amputation. The risk of that is between 1 in 1000 and 1 in 5000.
Other risks of the surgery include problems like heart attack, stroke or blood clots. It is possible to die after knee replacement. It is important to talk through the risks and benefits of the procedure and any specific concerns you have when making decisions about the surgery.
What about partial knee replacements?
A partial knee replacement is a unicompartmental knee replacement or patellofemoral knee replacement. The results of partial knee replacements can be very good when they are good but they are also less reliable than total knee replacements.
Recent research has indicated that if a person at any age has a partial knee replacement then they are at increased risk of developing a failed redo knee replacement by a given age in the future. That is mainly because partial knee replacements have a 2 to 3 times higher failure rate per year than total knee replacements. To minimise the risk of a patient finding themselves in a difficult situation, Dr Martin does not do partial knee replacement surgery.
Are blood clots a worry?
There are different types of blood clots you can get after a knee replacement, but there are steps that can be taken to protect against them.
A clot in the wound is called a haematoma. That can’t spread to the lungs so it isn’t dangerous in that way, but it is an infection risk. Very occasionally a knee replacement might need a haematoma cleaned out in the operating theatre. With current techniques the risk of a bad wound haematoma is very low.
The other sort of blood clots are ones in the leg veins (DVT) that can clog up the lungs (PE). A PE can be life-threatening, but there are a lot of different, effective measures that the team of people caring for a knee replacement patient take to make the risk of a dangerous PE very, very small.
Bruising-type colours up and down the leg after surgery are not clots. They are usually from some blood that has leaked out of the knee.
Is infection a worry?
Infection can be a major problem, so the surgical team takes a number of effective steps and great care to minimise the risk of infection spreading to a knee replacement.
An example of this is pre-operative screening and treatment of people who carry golden staph, whether it is the super-bug or more common “garden variety” type. About a third of people in the community carry the “garden variety” golden staph on their skin and special treatment to clear it, or the worse bug before surgery decreases the risk of infection.
With this and other steps the risk of infection is less than 1%.
Something that patients are not always aware of is that it is also possible for infection to spread to a new knee years after surgery, via bloodstream poisoning. Thaisis very unusual, but it is still worth taking steps to protect against it.
It is important to check with your doctor if you need antibiotics before future operations or procedures. If you are getting a recurrent infection somewhere, such as a kidney infection from a stone, then it is very important to treat the infection and fix the underlying issue to minimise the risk of spread to your knee on each occasion.
Do injections work for arthritis?
There are different types of injection available. Any injection has a small risk of infection.
Cortisone injections can give temporary relief. In general, these would be used to help pinpoint which pain was from where, rather than for on-going treatment. There are some lubrication-type injections. However, these are reasonably expensive and the research to support them is inconclusive. In practice they are a bit “hit and miss”.
Other injections include platelet-rich plasma or stem cells. These treatments are not yet at the point where they are useful in terms of making cartilage grow back. It is possible that stem cells may be useful in the future, but realistically that is a long way off. There are a lot of things wrong in a worn-out knee that would need fixing (probably also with an operation) for cartilage cells to really be useful.
What about a keyhole surgical clean out?
Keyhole knee surgery is called arthroscopy. There are a lot of things that a doctor can do through the arthroscope, including ligament reconstruction, meniscus repair or removal, cartilage surgery and removal of loose bits, but making a worn-out knee grow healthy cartilage again isn’t one of them. Keyhole surgery used to be done quite a lot for arthritis, but research has shown that it isn’t reliable. Some people feel better after it and some people are worse. Because of this, arthroscopic surgery for arthritis isn’t now seldom recommended.
How long will I need off work?
This is different from person to person and depends on the Job. Office type work may be possible 4 weeks after the surgery. Heavier work might be possible 6-8 weeks after the surgery. Some people will recover even more quickly and be able to return sooner, and some more slowly and need longer. It is also important to remember that in general driving isn’t recommended for 6 weeks, although some people may be able to drive earlier after discussion with the Doctor. Within 2-3 weeks after the surgery, you will be able to get a feel for whether an early return to work is feasible. Patients having both knees replaced would typically neeed a week longer than single sided surgery. The steps that Dr Martin takes to decrease pain and improve early function help make an earlier return to work achievable.