Knee Replacement

What is Knee Replacement?

In a Total Knee Replacement, the surgeon replaces your entire knee with an artificial joint. This is in contrast to Partial or Compartment-Specific Knee Replacement which involves replacing the damaged parts of the knee with parts made out of metal or plastic.

Knee Replacement is for treating knee pain that cannot be treated using other means such as medication, injections, weight loss or physical therapy.

Total Knee Replacement

if your knee has been severely damaged and continues to hurt, you may be a candidate for total knee replacement.knee painThis damage might have been caused by trauma during sports or an accident. Progressive and various types of arthritis also damages the knee badly enough for it to be replaced, the most common type being Osteoarthritis.There are those, however, whose steadily worsening condition significantly affects their daily routine, leading them to consider having a total knee replacement.

Partial Knee Replacement

To be a candidate for partial knee replacement, your arthritis must be limited to only one compartment of your knee. It is also important that you are not overweight to pass for surgery. The surgeon will also look at an X-ray to see whether your anterior cruciate ligament is in good shape, and if the damage is limited to just one compartment. He may also look at an MRI scan which will enable him to assess your knee’s cartilage.To find out if you are a good candidate for a partial knee replacement, the surgeon will ask you where exactly in your knee the pain is coming from. If your entire knee hurts or the pain is coming from under your kneecap, then a total knee replacement might be for you, instead.Overall, your knee must be stable, have minimal deformity, and be able to move to some extent. However, if you have weak or torn ligaments or your knee is extremely stiff, a compartment-specific knee replacement may not be for you. It is also not recommended for those suffering from inflammatory arthritis.

Total Knee Replacement

This is a major surgical procedure using artificial parts called prosthesis, and usually take between 1 to 2 hours.

In this procedure, the metal ends of the artificial joint will be attached to the ends of the femur (thigh bone) and the tibia (lower leg bone) using surgical cement. The femur and tibia will be adapted to receive the ends of the artificial joint by removing their end portions and replacing them with a piece of plastic that has a metal stem.

The surgeon might also place a button-like piece of plastic under the surface of the patella (kneecap) as needed.

Physical therapy will be started within 24 hours.

Partial Knee Replacement

Compared to having a total knee replacement, a partial knee replacement requires a much smaller incision, and because of this, a person who has this procedure ends up spending much less time confined after surgery.

The entire procedure takes about one to two hours. You will have a choice of either general or spinal anaesthesia, the former putting you to sleep or the latter numbing you from the waist down.

In this procedure, the surgeon replaces one or two areas or compartments of the knee’s three main compartments, which are the medial or inside area, the lateral or outside area, and the patellofemoral or the front area between the thighbone and kneecap. When two compartments are replaced, they are the medial and patellofemoral.

First, surgical saws will be used to remove the cartilage from the compartment to be replaced. Metal coverings will then be attached to the bone using surgical cement to take the place of the cartilage and bone that were removed. Finally, a smooth surface will be created by positioning a plastic insert between the metal coverings. The patient is then taken to the recovery area.

Total Knee Replacement

As with any major surgical procedure, having a total knee replacement carry the risks that come with the use of anaesthesia such as damage to the heart, lungs, kidneys and liver.

The risks specific to this procedure include pulmonary embolism, which is a blood clot in the legs that can affect the lungs, causing chest pain, shortness of breath, or shock. There is also the possibility that the prosthesis used during the procedure wears out or becomes loose.

Patients undergoing total knee replacement may likewise experience further pain and stiffness in the knees, knee infection, bleeding inside the knee itself, and fractures. They might also suffer from blood vessel injury and nerve damage, as well as nausea and vomiting brought on by the use of pain medications. Urinary Tract Infection is also a possibility.

Because of their tendency to move around a lot, younger patients might also be said to run the risk of added trauma to the knee replacement.

Partial Knee Replacement

Though patients lose less blood during a partial knee replacement versus a total knee replacement, and are able to regain their knee movement much more quickly, this doesn’t mean that they will never need a total knee replacement. If a person undergoes this procedure because of arthritis, the other parts of the knee that were not replaced might develop arthritis, as well.

In fact, at the beginning of the procedure proper, the surgeon will inspect your knee after making the incision to make sure that the damage really is limited to just one or two compartments and that your ligaments are sound. If not, there’s a chance that he will proceed with a total knee replacement, instead.

The risks of a compartment-specific knee replacement include infection, injuries to blood vessels and blot clots. The prosthesis might also become loose or fail altogether. Your knee joint might also feel rather stiff and your knee might still be painful.

Total Knee Replacement

Anyone considering a total knee replacement who weighs more than 91 kg is advised to prepare for the procedure by losing weight, as heavier body weight increases the risk of loosening or dislocating the replaced knee and slowing down recovery.

But before a patient can have a total knee replacement, the surgeon must first determine whether that patient is a good candidate for it via a series of tests.

He will evaluate the soundness of the hip and ankle adjacent to the damaged knee to make sure the patient will be able to recover satisfactorily from the procedure. If he were to replace a knee opposite an injured hip or ankle, it would affect the success of the procedure in addressing pain or loss of function.

The surgeon will likewise require an EKG, a chest X-ray and routine blood tests to rule out any major heart or lung diseases as well as anaemia, infection or metabolic anomalies.

Be sure to inform the surgeon of any allergies you may have to anaesthesia, medications, tape or latex, as well as any medications you are currently taking. Also let him know if you are or might be pregnant.

It also recommended to meet with the physical therapist you will be working with after surgery, as well as make arrangements for someone to be on hand to assist you, as your mobility will be limited.

Partial Knee Replacement

Knee Replacement

Preparing for this procedure takes about one month, during which time the surgeon discusses various options and possible outcomes with the patient. All the usual pre-operative tests will be done.

Your physical therapist will ask you to do exercises for strengthening your hip, knee and ankle, as well as exercises affecting your range of motion. You may also be asked to take an iron supplement to boost your haemoglobin, and to stop taking medications such as warfarin and aspirin to reduce bleeding.

Total Knee Replacement

How fast a patient recovers from a Knee Replacement depends on his full co-operation with physical therapy, which can start in just 48 hours after the procedure. Be sure to do the exercises which will be given to you to do at home for strengthening the calf and thigh muscles.

It is normal for the knee to hurt and to feel stiff to some extent during the first few days of therapy. Unless the physical therapist removes it during therapy, a knee immobiliser is recommended to be worn during walking and sleeping. Take extra care while using crutches or a walker, and with perseverance, you can gradually manage to walk and climb stairs.

The physical therapist might also recommend using a continuous passive motion (CPM) machine, which continuously moves the knee in pre-set ranges of motion during periods of relaxation. Using this machine can help lessen scarring and tissue contractions around the replaced knee, as well as improve circulation. Be sure to use this machine under supervision or as directed.

Also be sure to keep your knee clean and dry and to follow the surgeon’s bathing instructions to the letter. You might also have to keep your leg elevated and ice your knee. Take the prescribed pain medications, and notify the surgeon if you have a fever, your knee hurts more than usual, or if your knee is swollen, red, bleeding or leaking fluids.

Partial Knee Replacement

Some people who had a partial knee replacement are able to go home on the very same day. You will still feel some pain after the procedure, but pain medications can help make you more comfortable and able to heal up more quickly.

It usually takes about six to eight weeks to fully recover from a partial knee replacement, meaning you will be able to play tennis and other sports. Jogging, running and certain other high-impact activities, however, may not be recommended.

The best thing to do would be to co-operate fully with your physical therapist from the day you have the surgery to about two to four weeks afterwards. Take extra care while using a cane, crutches or a walker. Keep up your rehabilitation exercises to increase your range of motion and improve circulation.

Be sure to take your medication, which may include warfarin or aspirin, to prevent blood clot formation.

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