A total knee replacement (TKR) or total knee arthroplasty is a surgery used to replace a knee joint that is affected by arthritis.
Total Knee Replacement surgery replaces the arthritic knee joint with an artificial metal or plastic replacement parts called the 'prostheses'. These include replacing the:
- end of the femur (thigh bone)
- end of the tibia (shin bone)
- plastic inserted between them and
- usually the patella (knee cap).
The artificial knee joint is made from a surgical-grade metal alloy with a special wear resistant plastic insert. Total Knee Replacement surgery is one of the most successful operations available today with over 90% still functioning well at 15 years.
Prior to surgery you will usually have tried some conservative treatments such as simple analgesics, weight loss, anti-inflammatory medications, modification of your activities, canes, or physical therapy.
Once these have failed it is time to consider surgery.
Candidates for Total Knee Replacement
The procedure is usually recommended for older patients who suffer from pain and loss of function from arthritis and have failed results from other conservative methods of therapy.
Each patient is assessed individually but Total Knee Replacement candidature is far greater than partial knee replacement and can include candidates who are:
- between 20 to over 80 years of age
- suffering pain
- restricted mobility interferes with your lifestyle
The outcome of the surgery can address patients with a greater range of arthritic stages and conditions.
Benefits of Total Knee Replacement Surgery
The decision to proceed with TKR surgery is a cooperative one between you, Dr Edward Graham, family and other medical professionals.
The benefits following surgery are relief of symptoms of arthritis. These include
- Severe pain that limits your everyday activities including walking, shopping, visiting friends, getting in and out of chair, gardening, etc.
- Pain waking you at night
- Deformity- either bowleg or knock knees
- Stiffness
The benefits are that older patients or severe arthritic patient have a clear solution to help relieve symptoms and pain.
Components - Prostheses
The artificial knee joint consists of:
- An upper metal component shaped and sized to fit to femur bone contour
- A flat metal tibial component made of metal alloys fixed to the bone
- A plastic insert designed to bear significant wear
- A patellar button which resurfaces the back of your knee cap.
Total Knee Replacement Procedure
The procedure is designed to be performed with minimal local trauma;
- Dr Edward Graham cuts down to the bone to expose the bones of the knee joint.
- The damaged portions of the femur and tibia are then cut at the appropriate angles using specialized jigs.
- Trial components are then inserted to check the accuracy of these cuts and determine the thickness of plastic required to place in between these two components.
- The patella (knee cap) may be replaced depending on a number of factors and Dr Edward Graham’s choice.
- The real components are then inserted with or without cement and the knee is again checked to make sure things are working properly.
- The knee is then carefully closed the knee is dressed and bandaged.
Each knee is individual and knee replacements take this into account by having different sizes for your knee. If there is more than the usual amount of bone loss, sometimes extra pieces of metal or bone are added.
Exercise Preparation
To help prepare you for the surgery a preoperative physiotherapist appointment is required to:
- fit crutches.
- instruction on partial weight-bearing and crutches use.
- learning how to reduce inflammation (icing of the knees), and
- learn postoperative exercise (co contractions, leg lifts with the knee extended, etc).
Post Op Instructions
Wound
Keep dressings on the wound and keep wound dry for 7 days or until there is no further discharge from the wound. If the dressing gets wet it should be removed and changed. It is normal to have some redness around the wound. It does not necessarily signal infection. However if you experience fever, sweats or any significant discharge from the wound then you should contact your doctor, the hospital or Dr Graham immediately.
Walking and Exercises
You will be given exercises before your discharge from the hospital. You should continue these exercises at home. You may put full pressure on the leg unless otherwise advised. You may need the use of a walking stick or crutches in the first few weeks after surgery.
Driving
You should not drive until you have been reviewed by Dr Graham after your surgery.
Pain
It is normal to experience pain after any knee surgery. The amount of pain experienced varies between individuals and the type of surgery performed. Please make sure that you have been given some pain medication on your discharge from hospital. Take the medication as prescribed and as required.
Warning Signs
Contact Dr Graham, the hospital or your family doctor if any of these signs develop:- fresh bleeding from the wound
- discharge from the wound
- temperature, fever and chills
- pain in the calf
- shortness of breath
Return to Work
You may return to light work duties after 6 weeks. You will not be fit to perform work duties that involve:
- prolonged standing,
- heavy lifting,
- bending or
- excessive stair climbing