If your knee is severely damaged by arthritis or injury, it may be hard for you to perform simple activities, such as walking or climbing stairs. Sitting or waking pain may be felt.
If nonsurgical treatments such as medications, physiotherapy and steroid/hyaluronic acid injections have not reduced pain or are no longer helpful, you may want to consider total knee replacement surgery.
Knee replacement surgery (arthroplasty) is a safe and effective procedure to relieve pain, correct leg deformity, and help you resume normal activities.

Total knee replacements have been performed successfully at all ages. Although most patients who undergo total knee replacement are age 50 to 80, recommendations for surgery are based on a patient's pain and disability, not age.

In determining whether a knee replacement is right for you, an orthopedic surgeon assesses your knee's range of motion, stability and strength. X-rays help determine the extent of damage.

You may be offered knee replacement surgery if:

If there is severe pain, swelling and stiffness in the knee joint and mobility is reduced
it is hard to walk more than a few blocks without significant pain or you need to use a cane or walker
If the severity of your knee pain affects your daily life and sleep quality
Everyday tasks, such as shopping or getting out of the bath are difficult or impossible
If there is knee deformity
Feeling depressed due to pain and lack of movement
When work or social life becomes difficult

Before the procedure

Stay as active as possible. Strengthening the muscles around the knee will help heal.
If you can, continue to do gentle exercise, such as walking and swimming, in the weeks and months before your operation. The patient may be referred to a physiotherapist who will give auxiliary exercises.
Knee replacement surgery requires anesthesia. The patient's entry status and preference help the team decide whether to use general anesthesia, which makes you unconscious, or spinal cord anesthesia, which leaves you awake but does not make you feel pain from the waist down.
You'll be given an intravenous antibiotic before, during and after the procedure to help prevent post-surgical infection. You might also be given a nerve block around your knee to numb it. The numbness wears off gradually after the procedure.

How does the post-procedure process proceed?

Moving the foot and ankle will be encouraged, which increases blood flow to the leg muscles and helps prevent swelling and blood clots. Blood thinners are taken to provide more protection against swelling and clotting and a support hose or compression bandage/sock can be worn.

You will be asked to do frequent breathing exercises and gradually increase your activity level. At first, a walker or crutch will have to be used, and a physiotherapist will teach the patient exercises that will help with his strength.

It usually requires a few days of hospitalization, but recovery times may vary. Most people can stop using walking aids around 6 weeks after surgery and start driving after 8 to 10 weeks.

After being discharged, the patient gives advice on taking care of the knee at home. A physiotherapist will show you how to run the new knee. After leaving the hospital, physical therapy should be continued at home or at a center.

Your exercises should be done regularly as instructed, and for best recovery, all of your care team's instructions regarding wound care, diet, and exercise should be followed.

Realistic Expectations

An important factor in deciding whether to have total knee replacement surgery is understanding what the procedure can and can not do.

Most people who have total knee replacement surgery experience a dramatic reduction of knee pain and a significant improvement in the ability to perform common activities of daily living.

With normal use and activity, every knee replacement implant begins to wear in its plastic spacer. Excessive activity or weight may speed up this normal wear and may cause the knee replacement to loosen and become painful. Therefore, most surgeons advise against high-impact activities such as running, jogging, jumping, or other high-impact sports for the rest of your life after surgery.

Realistic activities following total knee replacement include unlimited walking, swimming, golf, driving, light hiking, biking, ballroom dancing, and other low-impact sports.

With appropriate activity modification, knee replacements can last for many years.

Possible Complications of Surgery

Knee replacement surgery is a common operation and most people do not have complications. However, as with any operation, there are risks as well as benefits.
Complications are rare but can include:

stiffness of the knee
infection of the wound
infection of the joint replacement, needing further surgery
unexpected bleeding into the knee joint
ligament, artery or nerve damage in the area around the knee joint
deep vein thrombosis (DVT)
persistent pain in the knee
fracture in the bone around the knee replacement during or after the operation

In some cases, the new knee joint may not be completely stable and further surgery may be needed to correct it.