Hamilton Health Sciences
Knee Replacement Surgery

Knee Replacement Surgery

Getting a new knee is major surgery and recovery takes time. With hard work and a positive outlook, you can get back to being active and enjoying life.

You may be anxious and excited as you wait for surgery. This is a good time to think about your feelings, lifestyle and habits, and make changes to help speed up your recovery. 

Why do I need a knee replacement?

You may need a knee replacement to:

  • lessen your pain
  • improve the function of your knee
  • make your knee more stable

Your surgeon will tell you why you are having a knee replacement. One of the most common reasons for a knee replacement is damage caused by osteoarthritis. Osteoarthritis, or OA, is a form of arthritis that causes the joints to wear out. Osteoarthritis usually affects the hips and knees and can result in pain, difficulty moving and eventually severe disability. Knee replacement surgery often provides a huge improvement in a person's life to help lessen your pain, improve the function of your knee and make your knee more stable.

Learn more about arthritis here.

How does the knee joint work?

knee anatomyThe knee joint works like a hinge. The thigh bone or femur in your upper leg is hinged to the shin bone, or tibia, or your lower leg.

The knee joint allows the shin bone to move backward and forward on the thigh bone so you can bend and straighten your leg.

3 things help the knee joint work easily and without pain: 

  • the smooth coating over the bones called cartilage

  • the slippery fluid inside the joint called synovial fluid

  • the muscles and ligaments which support and move the knee

3 things make the knee painful and hard to move:

  • the smooth coating over the bones gets rough,dry and worn away

  • the muscles weaken and the knee gets stiff

  • the slippery synovial fluid begins to dry up

What is knee replacement?

Your surgeon removes the old knee joint and puts in a new joint. This is call a knee replacement or a total knee arthroplasty. Your new knee joint is made of metal and plastic. One part of the new joint goes over the end of the thigh bone and the other part attaches to the shin bone. These new parts make the knee joint smooth again. A small button may be placed under the surface of the knee cap. The knee cap is called the patella.

Some people have only part of the joint replaced. This is called a hemiarthroplasty.

There are different types of knee replacements:

  • a cemented joint uses a special cement or glue to hold the new parts in place.
  • a non-cemented joint has a special coating to help the bone grow into the new joint and hold it in place


  knee replacement


Your surgeon will tell you what type of knee replacement you need.

Can I have both knees done at the same time?

To have both of your knees replaced at the same time depends on several factors, including your overall health and your weight. Your surgeon will discuss this option with you.

If you have both knees done at the same time your recovery is slower than just having one done. Your hospital stay may be longer.

Hamilton Health Sciences • Hamilton, Ontario • 905.521.2100

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