Total Knee Replacement
What is Total Knee Replacement?
The knee joint is a hinge joint made up of the lower end of the thighbone (femur) which hinges on the upper end of the tibia, and the kneecap (patella), which slides along a groove on the end of the femur. Total knee replacement is a surgical procedure in which a painful or poorly functioning part of the knee is replaced with prosthetic components to help reduce symptoms and restore mobility in the joint. It is like "retreading an old tyre" where the original rubber tyre is maintained while the outer layer alone is changed or replaced with a brand new layer.
Parts of the Knee Prosthesis
The prosthetic knee is designed to replace the damaged part of patient’s knee joint. It is made of the following components:
- Femoral component: This replaces the lower end of the thighbone (femur). It is made of metal. It is shaped to match the natural contour of the femur.
- Tibial component: This replaces the top end of the shinbone (tibia). It is made of a metal tray that holds a plastic bearing surface that glides against the femoral component.
When should Total Knee Replacement be considered?
A knee that is painful as a result of osteoarthritis , injury or chronic inflammatory desease can severely affect your ability to lead an active life.
What to expect during Total Knee Replacement Surgery
The operation is performed under spinal. An incision is made down the front of the knee. The patella is dislocated and inverted to expose the inside of the knee joint. Soft tissues are moved out of the way with retractors. The arthritic or injured joint surfaces in the femur, tibia are shaped with special cutting guides and instruments so the prosthetic components fit properly. The prosthetic components are then temporarily placed in position and the knee is assessed for stability and mobility. The components are then permanently inserted into position. Special cement may be used to attach the prosthesis to the bone. The incision is then closed in layers with sutures. A bandage is then applied and you will be transferred to the recovery room.
Hospital stay after the procedure varies between 1-4 days. You will be discharged home when can safely get out of bed, walk with the assistance of a walker or crutches and use the stairs safely. You will be instructed on physical therapy exercises to help you recover quickly. Full recovery from total knee replacement may take about 3 months.
Longevity and long term functional returns
Most of the functions expected by Indian patients like sitting crosslegged and sintting on the floor ascending & descending stairs are easily performed by most of the patients.Dr Laxman Advises to use high flexion knee implants.
Most of the knees perform well for 20-25 years if instructions are followed & lifestyle modifications are applied.
When Dr Rewat suggests a total knee replacement you will most probably have a lot of queries.
Here, he address the most common queries we get from our patients.
Do I really need surgery.
Surgery is generally recommended to you if the pain is unbearable , Anti inflammatory medications,lifestyle modifications are not effective any more , you are restricted in your activities and dependency on others have increased off late .other indications like deformities (bow legs ,knock knees).
What happens during surgery, and how long does it take?
- The doctor will make an incision over the front of your knee to expose the damaged area of your joint.
- The standard incision size varies from approximately 4-5 inches in length.
- During the operation, damaged joint surfaces are reshaped.
- They then replace the damaged tissue with new metal and polyethylene components.
- The components combine to form an artificial joint that is biologically compatible and mimics the movement of your natural knee.
- Most knee replacement procedures take 30 to 45 minutes to complete.
What are the knee implants?
Knee implants consist of metal and medical-grade plastic called polyethylene.
Dr Rewat Uses Hi-Flex variety which gives better stability and maximum bending in his patients.
Average knee replacements survive for 25 years.
Which anesthesia will be given to me? is it safe?
Any operation done with anesthesia has its own risks.Risk can be minimised by a thorough Pre anaesthetic checkup and systemic evaluation (fitness for surgery) by the experts.cardiologist and physician’s opinion is sought by Dr Rewat regarding your fitness for surgery.Risks are generally categorised as mild ,moderate or severe and optimisation options are spelled out.
The options for TKR include:
- Spinal or epidural
- A regional nerve block anesthesia
An anesthesia team will decide on the most suitable options for you but most knee replacement surgery is done using a combination of the above.
How much pain will I have after surgery?
There will be minimal pain after your operation but your surgery team will do everything possible to keep it manageable.
You will y receive a nerve block prior to your operation and your surgeon may also use a long-acting local anesthetic during the procedure to help with pain relief after the procedure.
When you leave the hospital, the doctor will give you pain relief medication as pills or tablets.
After you recover from surgery, your knee should be significantly less painful than it was before.
Following your doctor’s instructions after surgery is the best way to manage pain, comply with physical therapy and achieve the best result possible.
Your doctor will also prescribe intravenous antibiotics to reduce the risk of infection.
What can I expect during recovery and rehabilitation?
Most people are up and walking by the same evening with the aid of a walker or crutches.
Following your operation, a physical therapist will help you bend and straighten your knee, get out of bed, and ultimately learn to walk with your new knee. This is often done on the same day of your operation.
Most people are discharged from the hospital 2–3 days after surgery.
After you return home, therapy will continue regularly for several weeks. Specific exercises will aim to improve the functionality of the knee.
Most people recover within 4-6weeks.