What is knee replacement surgery?


Is total knee replacement surgery for you?

If you are considering knee replacement surgery, you have plenty of company. The Agency for Healthcare Research and Quality reports that more than 600,000 knee replacements are performed each year in the United States.1

Even better news is that the US Department of Health and Human services considers total knee replacement to be one of the most successful and cost effective interventions in medicine. In fact, the success rate for knee replacements 10 years after surgery is 90-95%.1

This surgery is intended for people with severe knee damage, due to injury or to arthritis-related deterioration of the joint. Knee replacement can relieve pain and allow you to be more active. Your doctor may recommend it if you have persistent knee pain, and medicine and other treatments are not helping you anymore.

The decision to have knee replacement surgery should be a cooperative one made by you, your family, your primary care doctor, and your orthopaedic surgeon. The process of making this decision typically begins with a referral by your primary care doctor to an orthopaedic surgeon for an initial evaluation.

How is knee replacement surgery performed?

Knee Surgery

During knee replacement surgery, the surgeon surgically removes the damaged bone and cartilage of the joint and replaces it with smooth, artificial implants - thereby eliminating painful bone-on-bone contact.

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

  • 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 kneecap, sits
  • Finally, the patellar component replaces the surface of the kneecap, 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

Important safety notes

Individual results of joint replacement vary. Implants are intended to relieve knee pain and improve function, but may not produce the same feel or function as your original knee. There are potential risks with knee replacement surgery such as loosening, wear and infection that may result in the need for additional surgery. Patients should not perform high impact activities such as running and jumping unless their surgeon tells them that the bone has healed and these activities are acceptable. Early device failure, breakage or loosening may occur if a surgeon's limitations on activity level are not followed.

1. American Academy of Orthopaedic Surgeons website, accessed March 7, 2017: http://orthoinfo.aaos.org/topic.cfm?topic=A00389

The information listed on this site is for informational and educational purposes and is not meant as medical advice. Every patient's case is unique and each patient should follow his or her doctor's specific instructions. Please discuss nutrition, medication and treatment options with your doctor to make sure you are getting the proper care for your particular situation.