Knee replacements have become a much more common operation over the last decade, due to both advances in surgery, surgical technique and the quality of the implants. As many knee replacements are being performed each year as hip replacements. Every year thousands are performed and as a general rule, 96% of them do extremely well.

The knee joint is opened up from the front of the knee with care taken to preserve the knee cap and quadriceps muscles. The end of the femur and then tibia are shaved of a few mm’s of bone and cartilage. This shaving is done with precision instruments and in my practice I always use´navigation'(a very advanced computer assisted device) to ensure than my bone cuts are accurate to within 1mm and 1 degree. This level of accuracy is just not possible using old fashioned conventional techniques and I believe is one of the major reasons knee replacement surgery has become so successful in terms of level of function and pain relief for patients. The knee is then assessed with a trial prosthesis(artificial knee) and is balanced (ie equal tension between the various ligaments and tendons). The bone surfaces are prepared and the prosthesis is then inserted using special cement to hold the components firmly to the bone. I then check that the knee moves as it should do using the navigation computer. Sometimes I will resurface the underside of the patella (kneecap), but in most occasions I don’t. The muscles and tendons are then sutured and repaired to where they were cut from.

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Prior to surgery you will be seen by myself and my anaesthetist and the procedure and the anaesthetic options will be discussed thoroughly with you.  On the day of surgery, it is important that you do not eat and drink anything after 2.00am, which ensures that your stomach is empty and significantly reduces any risk of aspirating stomach contents during the procedure.  I will mark your limb and obtain your signature for consent and then you will proceed down to the operating theatre.

The knee joint is opened up from the front of the knee with care taken to preserve the knee cap and quadriceps muscles. The end of the femur and then tibia are shaved of a few mm’s of bone and cartilage. This shaving is done with precision instruments and in my practice I always use “navigation” (a very advanced computer assisted device) to ensure than my bone cuts are accurate to within 1mm and 1 degree. This level of accuracy is just not possible using old fashioned conventional techniques and I believe is one of the major reasons knee replacement surgery has become so successful in terms of level of function and pain relief for patients. The knee is then assessed with a trial prosthesis(artificial knee) and is ‘balanced’ (ie equal tension between the various ligaments and tendons). The bone surfaces are prepared and the prosthesis is then inserted using special cement to hold the components firmly to the bone. I then check that the knee moves as it should do using the navigation/ computer. Sometimes I will resurface the underside of the patella (kneecap), but in most occasions I don’t. The muscles and tendons are then sutured and repaired to where they were cut from.

The post-operative course in hospital

In your postoperative course as an in-patient, which is approximately 3-5 days, you will be seen daily by either myself or my anaesthetist, by the physiotherapist and obviously you will be looked after by the nursing staff.  During that time, we aim to turn you from an anxious patient with a painful knee back into a reassured, pain-free 25-year-old (!) who will feel confident in going back into the outside world and taking up all your old hobbies, activities and sports.  I am proud to work at Southern Cross North Harbour and feel that the standard of care patients receive is exceptionally high and second to none.  The dedication of the nursing staff and allied health care professionals is exemplary and I would have every confidence in a member of my family going there for surgical or medical treatment.

Recovery from surgery once home

Different people recover at different rates. The final success of a knee replacement is many years of pain-free normal knee function.  To achieve this goal, it is necessary to do some rehabilitation and generally look after yourself.

  • It is important to walk every day, as this increases muscle, ligament and tendon strength. It will rebuild your muscles that will have become wasted as a result of the painful arthritis, and it will help to increase the density of your bone, preventing osteoporosis.
  • It is important to take good care of your skin, both on the operated site and around the rest of the body.  Your skin is a protective barrier against infection and any breach in this barrier could potentially allow infection into the blood supply, which may result in seeding of the infection in the artificial knee joint.  This in itself is likely to require a significant amount of further treatment (both surgery and medical treatment) to cure the infection.
  • Dental hygiene should be a high priority and any abscesses should be dealt with prior to knee replacement surgery.  Following knee replacement surgery, it is important that abscesses are treated promptly and comprehensively with antibiotics to stop infection travelling in the blood supply around to the knee joint.

Recovery from surgery once home

Different people recover at different rates. The final success of a hip replacement is many years of pain-free hip function. To achieve this goal, it is necessary to do some rehabilitation and generally look after yourself.

 

  • It is important to walk every day, as this increases muscle, ligament and tendon strength. It will rebuild your muscles that will have become wasted as a result of the painful arthritis, and it will help to increase the density of your bone, preventing osteoporosis.
  • It is important to take good care of your skin, both on the operated site and around the rest of the body. Your skin is a protective barrier against infection and any breach in this barrier could potentially allow infection into the blood supply, which may result in seeding of the infection in the artificial hip joint. This in itself is likely to require a significant amount of further treatment (both surgery and medical treatment) to cure the infection.
  • Dental hygiene should be a high priority and any abscesses should be dealt with prior to hip replacement surgery. Following hip replacement surgery, it is important that abscesses are treated promptly and comprehensively with antibiotics to stop infection travelling in the blood supply around to the hip joint.
  • Most hip joints are designed to give you almost normal hip movement. However this is not a completely normal movement. There is one particular movement which should not be attempted as this may result in a dislocation (the ball coming out of the socket – extremely painful!). This position, WHICH SHOULD BE AVOIDED, is with the knee bent up and in, and the foot bent up and out. I will run over the safe and the unsafe positions with you both before and after surgery and if you ever have any concerns, just remember both knees and ankles together is safe.

Potential risks and complications

  • Deep vein thrombosis/pulmonary embolism (DVT/PE) – blood clots in the veins in the legs or lungs
  • Neurovascular injury – damage to nerves or blood vessels
  • Infection – which can be superficial in the wound or deep in the new joint
  • Fracture – where the bone breaks around the knee joint
  • Myocardial infarct (heart attack) or CVA (stroke).
  • Stiffness – the importance of rehabilitation and physiotherapy
  • Leg swelling and stiffness – this always occurs to a greater or lesser extent and resolves over 4-6 weeks
  • Pain
  • Haematoma (an accumulation of blood around the surgical site that may require drainage.
  • Loss of blood during surgery that may require a blood transfusion.
  • Numbness, pain or itchiness around the scar.

What causes knee problems/ pain?

There are a number of causes for knee problems. The most common is osteoarthritis (wear and tear, generally related to age). Rheumatoid arthritis is a condition whereby the lining of the joint becomes extremely inflamed and starts to destroy the healthy articular cartilage. A knee replacement is also called a, knee arthroplasty (the technical term). It can be a Total knee arthroplasty ( a whole knee replacement) or a Uni-compartmental knee replacement (half a knee replacement). Its aim is to alleviate pain and provide a near-normal range of movement.

Can I have both knees done at once?

In some cases it may be best to replace both knee joints during the same operation. This tends to be in some patients who are confined to a wheelchair or who suffer from extreme stiffness or pain and think that rehabilitation after one may be made extremely difficult because of arthritis in the other knee. Recovery and rehabilitation tend to be a little bit more difficult and uncomfortable in the first few weeks after surgery, but there is the advantage of less total time off work for recovery.

 

When should I have surgery?

The decision for surgery should be made by the patient in conjunction with the orthopaedic surgeon. In the vast majority of cases, the decision should be made by the patient, only rarely should an orthopaedic surgeon persuade a patient to consider a knee replacement sooner rather than later (e.g. concerns that the bone is wearing out, which would mean that the surgical technique becomes significantly more difficult and this may result in a less successful outcome). Most patients deciding on surgery will be having pain on a daily basis. There is often a constant underlying baseline ache, which is made worse by certain movements, activities or positions (e.g. going for a walk, going up or down stairs, getting in and out of a car or trying to put on shoes and socks). In the first instance, simple pain relief such as Panadol may help with these symptoms. Often patients who are able to take anti-inflammatory medication will find good relief of their symptoms and sometimes stronger painkillers, which are prescribed by a medical professional, will be required as the knee pain worsens. Quite often, the pain will get worse at night and may even keep people awake, or wake people up from sleep.Physiotherapy and various activities and movements, such as swimming, may also be beneficial to the joint and may help relieve some of the pain and stiffness. The stiffness typically makes it difficult to sit in a low chair, go up or down stairs easily, put on shoes and socks and paint or clip toenails / wash between the toes. Whilst painkillers and anti-inflammatory medication, exercise modification and walking aids, e.g. walking stick may help the symptoms, they will not cure the diseased knee. The knee will slowly deteriorate and it is at this point when non-operative measures have been tried and exhausted, most orthopaedic surgeons would recommend the consideration of joint replacement.

All patients who have had a knee replacement will be seen approximately 6-8 weeks after surgery in an outpatient clinic. Further questions can be answered and it is about this time that I tend to suggest an activity-based rehabilitation programme to increase peoples strength, fitness and stamina. The recovery up to the 6-week mark is generally the same for most people and I would advise avoiding the gym or swimming for the majority of this time.

 

Driving

The issue of driving depends upon the patient, which hip has been operated on and whether it is a manual or an automatic gearbox on the car. As a general rule, most insurance companies would not cover a driver if he/she was involved in an accident and had had a knee replacement within 6 weeks of the accident. After 6 weeks, it is generally considered that a patient is safe to drive and perform an emergency stop. This is not just the simple mechanics of pushing on a pedal with the foot, but also whether someone is still requiring pain relief medication, which can cloud judgement, swiftness or response and manual dexterity. Thus, at 6 weeks, most patients do not require any form of pain relief and are mobile enough to get in and out of the car and perform the physical act of driving. Most patients, I find, are able to drive to their first outpatient consultation which may be at about the 6 week mark, and I would suggest having a gentle try-out a few days before, doing small distances.

 

When can I return to work?

I would suggest that most patients have approximately 6 weeks off work, if still in employment, for very similar reasons to those given above for driving. It is important to rehabilitate and do the exercises that will be shown to you in hospital and also it is my experience that after this form of surgery, most patients are really quite tired for 3-4 weeks and require more sleep and rest than usual. Obviously, each individual’s job should be taken into account and I can discuss this further with you when we meet up.

 

How long will my new knee last?

We do not know exactly how long an individual knee will last. It will vary, depending on the type of knee replacement (prosthesis), the surgical technique, the activity level of the patient, other patient factors (e.g. co-morbidities, obesity) and a little bit of luck. When a knee replacement wears out, it is still possible in almost every case to revise the knee and put in a new knee joint. However, the complications and the risks associated with revision surgery are slightly higher than with surgery first time around. The long-term results are also slightly less predictable.

+ Proceedure

Prior to surgery you will be seen by myself and my anaesthetist and the procedure and the anaesthetic options will be discussed thoroughly with you.  On the day of surgery, it is important that you do not eat and drink anything after 2.00am, which ensures that your stomach is empty and significantly reduces any risk of aspirating stomach contents during the procedure.  I will mark your limb and obtain your signature for consent and then you will proceed down to the operating theatre.

The knee joint is opened up from the front of the knee with care taken to preserve the knee cap and quadriceps muscles. The end of the femur and then tibia are shaved of a few mm’s of bone and cartilage. This shaving is done with precision instruments and in my practice I always use “navigation” (a very advanced computer assisted device) to ensure than my bone cuts are accurate to within 1mm and 1 degree. This level of accuracy is just not possible using old fashioned conventional techniques and I believe is one of the major reasons knee replacement surgery has become so successful in terms of level of function and pain relief for patients. The knee is then assessed with a trial prosthesis(artificial knee) and is ‘balanced’ (ie equal tension between the various ligaments and tendons). The bone surfaces are prepared and the prosthesis is then inserted using special cement to hold the components firmly to the bone. I then check that the knee moves as it should do using the navigation/ computer. Sometimes I will resurface the underside of the patella (kneecap), but in most occasions I don’t. The muscles and tendons are then sutured and repaired to where they were cut from.

+ Post operative course

The post-operative course in hospital

In your postoperative course as an in-patient, which is approximately 3-5 days, you will be seen daily by either myself or my anaesthetist, by the physiotherapist and obviously you will be looked after by the nursing staff.  During that time, we aim to turn you from an anxious patient with a painful knee back into a reassured, pain-free 25-year-old (!) who will feel confident in going back into the outside world and taking up all your old hobbies, activities and sports.  I am proud to work at Southern Cross North Harbour and feel that the standard of care patients receive is exceptionally high and second to none.  The dedication of the nursing staff and allied health care professionals is exemplary and I would have every confidence in a member of my family going there for surgical or medical treatment.

Recovery from surgery once home

Different people recover at different rates. The final success of a knee replacement is many years of pain-free normal knee function.  To achieve this goal, it is necessary to do some rehabilitation and generally look after yourself.

  • It is important to walk every day, as this increases muscle, ligament and tendon strength. It will rebuild your muscles that will have become wasted as a result of the painful arthritis, and it will help to increase the density of your bone, preventing osteoporosis.
  • It is important to take good care of your skin, both on the operated site and around the rest of the body.  Your skin is a protective barrier against infection and any breach in this barrier could potentially allow infection into the blood supply, which may result in seeding of the infection in the artificial knee joint.  This in itself is likely to require a significant amount of further treatment (both surgery and medical treatment) to cure the infection.
  • Dental hygiene should be a high priority and any abscesses should be dealt with prior to knee replacement surgery.  Following knee replacement surgery, it is important that abscesses are treated promptly and comprehensively with antibiotics to stop infection travelling in the blood supply around to the knee joint.
+ Recovery

Recovery from surgery once home

Different people recover at different rates. The final success of a hip replacement is many years of pain-free hip function. To achieve this goal, it is necessary to do some rehabilitation and generally look after yourself.

 

  • It is important to walk every day, as this increases muscle, ligament and tendon strength. It will rebuild your muscles that will have become wasted as a result of the painful arthritis, and it will help to increase the density of your bone, preventing osteoporosis.
  • It is important to take good care of your skin, both on the operated site and around the rest of the body. Your skin is a protective barrier against infection and any breach in this barrier could potentially allow infection into the blood supply, which may result in seeding of the infection in the artificial hip joint. This in itself is likely to require a significant amount of further treatment (both surgery and medical treatment) to cure the infection.
  • Dental hygiene should be a high priority and any abscesses should be dealt with prior to hip replacement surgery. Following hip replacement surgery, it is important that abscesses are treated promptly and comprehensively with antibiotics to stop infection travelling in the blood supply around to the hip joint.
  • Most hip joints are designed to give you almost normal hip movement. However this is not a completely normal movement. There is one particular movement which should not be attempted as this may result in a dislocation (the ball coming out of the socket – extremely painful!). This position, WHICH SHOULD BE AVOIDED, is with the knee bent up and in, and the foot bent up and out. I will run over the safe and the unsafe positions with you both before and after surgery and if you ever have any concerns, just remember both knees and ankles together is safe.
+ Complications/Risks

Potential risks and complications

  • Deep vein thrombosis/pulmonary embolism (DVT/PE) – blood clots in the veins in the legs or lungs
  • Neurovascular injury – damage to nerves or blood vessels
  • Infection – which can be superficial in the wound or deep in the new joint
  • Fracture – where the bone breaks around the knee joint
  • Myocardial infarct (heart attack) or CVA (stroke).
  • Stiffness – the importance of rehabilitation and physiotherapy
  • Leg swelling and stiffness – this always occurs to a greater or lesser extent and resolves over 4-6 weeks
  • Pain
  • Haematoma (an accumulation of blood around the surgical site that may require drainage.
  • Loss of blood during surgery that may require a blood transfusion.
  • Numbness, pain or itchiness around the scar.
+ FAQ's

What causes knee problems/ pain?

There are a number of causes for knee problems. The most common is osteoarthritis (wear and tear, generally related to age). Rheumatoid arthritis is a condition whereby the lining of the joint becomes extremely inflamed and starts to destroy the healthy articular cartilage. A knee replacement is also called a, knee arthroplasty (the technical term). It can be a Total knee arthroplasty ( a whole knee replacement) or a Uni-compartmental knee replacement (half a knee replacement). Its aim is to alleviate pain and provide a near-normal range of movement.

Can I have both knees done at once?

In some cases it may be best to replace both knee joints during the same operation. This tends to be in some patients who are confined to a wheelchair or who suffer from extreme stiffness or pain and think that rehabilitation after one may be made extremely difficult because of arthritis in the other knee. Recovery and rehabilitation tend to be a little bit more difficult and uncomfortable in the first few weeks after surgery, but there is the advantage of less total time off work for recovery.

 

When should I have surgery?

The decision for surgery should be made by the patient in conjunction with the orthopaedic surgeon. In the vast majority of cases, the decision should be made by the patient, only rarely should an orthopaedic surgeon persuade a patient to consider a knee replacement sooner rather than later (e.g. concerns that the bone is wearing out, which would mean that the surgical technique becomes significantly more difficult and this may result in a less successful outcome). Most patients deciding on surgery will be having pain on a daily basis. There is often a constant underlying baseline ache, which is made worse by certain movements, activities or positions (e.g. going for a walk, going up or down stairs, getting in and out of a car or trying to put on shoes and socks). In the first instance, simple pain relief such as Panadol may help with these symptoms. Often patients who are able to take anti-inflammatory medication will find good relief of their symptoms and sometimes stronger painkillers, which are prescribed by a medical professional, will be required as the knee pain worsens. Quite often, the pain will get worse at night and may even keep people awake, or wake people up from sleep.Physiotherapy and various activities and movements, such as swimming, may also be beneficial to the joint and may help relieve some of the pain and stiffness. The stiffness typically makes it difficult to sit in a low chair, go up or down stairs easily, put on shoes and socks and paint or clip toenails / wash between the toes. Whilst painkillers and anti-inflammatory medication, exercise modification and walking aids, e.g. walking stick may help the symptoms, they will not cure the diseased knee. The knee will slowly deteriorate and it is at this point when non-operative measures have been tried and exhausted, most orthopaedic surgeons would recommend the consideration of joint replacement.

+ Follow-up and surveillance

All patients who have had a knee replacement will be seen approximately 6-8 weeks after surgery in an outpatient clinic. Further questions can be answered and it is about this time that I tend to suggest an activity-based rehabilitation programme to increase peoples strength, fitness and stamina. The recovery up to the 6-week mark is generally the same for most people and I would advise avoiding the gym or swimming for the majority of this time.

 

Driving

The issue of driving depends upon the patient, which hip has been operated on and whether it is a manual or an automatic gearbox on the car. As a general rule, most insurance companies would not cover a driver if he/she was involved in an accident and had had a knee replacement within 6 weeks of the accident. After 6 weeks, it is generally considered that a patient is safe to drive and perform an emergency stop. This is not just the simple mechanics of pushing on a pedal with the foot, but also whether someone is still requiring pain relief medication, which can cloud judgement, swiftness or response and manual dexterity. Thus, at 6 weeks, most patients do not require any form of pain relief and are mobile enough to get in and out of the car and perform the physical act of driving. Most patients, I find, are able to drive to their first outpatient consultation which may be at about the 6 week mark, and I would suggest having a gentle try-out a few days before, doing small distances.

 

When can I return to work?

I would suggest that most patients have approximately 6 weeks off work, if still in employment, for very similar reasons to those given above for driving. It is important to rehabilitate and do the exercises that will be shown to you in hospital and also it is my experience that after this form of surgery, most patients are really quite tired for 3-4 weeks and require more sleep and rest than usual. Obviously, each individual’s job should be taken into account and I can discuss this further with you when we meet up.

 

How long will my new knee last?

We do not know exactly how long an individual knee will last. It will vary, depending on the type of knee replacement (prosthesis), the surgical technique, the activity level of the patient, other patient factors (e.g. co-morbidities, obesity) and a little bit of luck. When a knee replacement wears out, it is still possible in almost every case to revise the knee and put in a new knee joint. However, the complications and the risks associated with revision surgery are slightly higher than with surgery first time around. The long-term results are also slightly less predictable.

+ Useful Links