Partial or Total knee replacement

Partial Knee Replacement Surgery

If you are considering knee surgery, the following partial knee replacement information may help you understand your alternatives. Your doctor must assess your specific circumstances, and guide you on what the options available, and appropriate, for you are. Remember that even if you may think an option may be right for you, there may be specifics in your circumstances that require different options.  Knee pain from arthritis can be particularly debilitating because we use our knees in almost all of our daily activities. If you are experiencing severe knee pain that interferes with your normal functioning, your doctor may recommend a partial knee replacement, also known as uni-compartmental knee replacement.

This procedure is much less invasive than total knee replacement and may give relief to people suffering from arthritis of the knee or a knee injury. Partial knee replacement surgery replaces only the damaged area of your knee joint, may require only one day of hospitalisation, and results in less recovery time when compared with total knee replacement surgery.

The knee can be divided into three compartments: the medial (inside) compartment, the lateral (outside) compartment, and the patello-femoral compartment. The uni-compartmental implant is designed to replace either the medial (inside) or lateral (outside) compartment.

The x-ray below shows a right leg with a lost medial (inside) compartment. Notice how there is no space between the femur (thigh bone) and the tibia (shin bone). This bone on bone contact can be quite painful.  

Uni-compartmental Osteoarthritis

Post-operative View with Implant

Watch a video on partial replacement procedure:

Total Knee Replacement Surgery

If you have spoken to your doctor and knee surgery is recommended as an option, the following total knee replacement information might help you understand the procedure and implants better. Your knees work hard during your daily routine, and arthritis of the knee or a knee injury can make it hard for you to perform normal tasks. If your injury or arthritis is severe, you may begin to experience pain when you’re sitting down or trying to sleep.

Sometimes a total knee replacement is the only option for reducing pain and restoring your activity level. If you and your doctor decide a total knee replacement is right for you, the following information will give you an understanding about what to expect.

A total knee replacement involves cutting away the damaged bone of the knee joint and replacing it with a prosthesis. This “new joint” prevents the bones from rubbing together and provides a smooth knee joint.

Implant Components

Almost all knee replacement implants consist of a four-part system: knee Implant compoents

  • The tibial (shin) side has two elements and replaces the top of the shin bone. This portion of the implant is made up of a metal tray attached directly to the bone and a plastic spacer that provides the lower half of the new joint's bearing surface.

  • The femoral (thigh bone) side is a single element that replaces the bottom of the thigh bone and provides the top half of the new joint's bearing surface. This component also replaces the groove where the patella, or knee cap, sits.

  • Finally, the patellar component replaces the surface of the knee cap, which rubs against the femur. The patella protects the joint, and the newly resurfaced patellar button will slide smoothly on the front of the joint.