An Overview of Custom Total Knee Replacement

Knee replacement surgery is the last-resort treatment for patients with severe knee arthritis. A new type of knee replacement that has received attention from healthcare professionals is called a “custom knee replacement.”

Doctor explaining the knee replacement treatment to senior patient
Luis Alvarez / Getty Images

Standard Knee Replacement Surgery

A knee replacement implant has three basic parts, called components. The tibial component of the knee replacement sits on top of the shin bone. The femoral component fits on the end of the thigh bone. Between these metal implants is a plastic component called the spacer. Occasionally, a fourth component is a small plastic piece that fits on the back side of your kneecap.

Historically, knee replacement surgery involves cutting away a portion of your shin bone and thigh bone and replacing those parts of your knee joint with a metal prosthesis. Most knee replacements prostheses were "off the shelf," meaning they would be about your size and a close fit, but not customized to your knee. Customized knee replacements are looking to change that aspect of joint replacement surgery.

Custom Knee Replacements

A custom knee replacement is similar to standard knee implants in that the same types of parts are used as described above. But prior to surgery with custom knee replacements, you will have a computerized tomography (CT or CAT) scan. This is a detailed image of the bony anatomy of your hip, knee, and ankle. Your surgeon can use the information from this scan to carefully examine 3D images of your joints. Then, computerized technology is used to measure the size, shape, and position of your knee joint and lower extremity. A total knee joint prosthesis is then fabricated to fit the exact shape and contour of your knee.

Benefits of Custom Knee Joint Replacement

There certainly are possible benefits of a custom knee replacement system, including:

  • Improved fit of your knee joint prosthesis
  • Decreased bone cutting during surgery
  • Preservation of your knee’s natural shape and joint line
  • The option to use custom knee replacements for the total joint or partial joint replacement

Because the prosthesis is custom made for your knee, less work has to be done at the time of surgery to determine alignment and ensure the knee implant will be properly positioned. Some surgeons also feel that the operation can be done more quickly, with less tissue disruption. The hope for the long-term is that if the implants of a knee replacement can be placed more accurately, they may last longer by not wearing out as quickly and provide patients with improved mobility.

Is a Newer System Better?

Since customized total knee replacement surgery is a relatively new concept, there is limited research to determine if the use of custom prostheses provides superior results when compared to the standard “off-the-shelf” knee replacement hardware. Initial studies indicate that customized knee replacement may better replicate joint motion and kinetics of an actual human knee. This may lead to improved overall satisfaction with mobility in patients undergoing knee joint replacement surgery. No increase in adverse events during surgery is demonstrated with customized knee replacements when compared to standard total knee replacement surgery.

There is no concrete data to show that this system is any better than other knee replacements your healthcare provider may recommend. In fact, some medical professionals may argue there is not enough data (yet) to recommend this system over other standard knee joint replacement systems that have longer-term results.

A Word From Verywell

Custom knee replacement is an exciting development in knee replacement surgery. Previously, customized knee replacement simply meant that the knee was studied prior to surgery and the best cuts were made to the joint that optimized surgical outcome. Now, customized knee joint replacement is just that—prior to surgery, your orthopedist will use computer technology to build your artificial knee so that it fits exactly to the contour of your actual knee joint. This may one day prove to provide you with superior results with total knee replacement surgery.

The best course of action: Learn all you can about standard and customized total knee replacement surgery and discuss your specific case with your healthcare provider and orthopedic surgeon. That way, you can be sure to get the right treatment for your knee.

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.

By Brett Sears, PT
Brett Sears, PT, MDT, is a physical therapist with over 20 years of experience in orthopedic and hospital-based therapy.