Legacy Meridian Park implements robotic knee replacement procedure

Legacy Meridian Park implements robotic knee replacement procedure

Portland native Christine Poulsen got a new knee in April, thanks to what she calls "The Robot."

"The Robot" is a new robotic arm-assisted technology from medical technology firm Stryker Corportation. Legacy Meridian Park Medical Center was the first hospital in Oregon to implement the "Mako Robotic Arm-Assisted Total Knee Procedure" for knee replacements after orthopedic surgeon Christopher Nanson was selected by Stryker for the limited market release of the technology.

Nanson said the Mako Total Knee represents the "future of knee replacements." And though its impact on recovery has yet to be studied, Poulsen said she thinks her recovery after the new procedure has been quicker and easier than with her first knee replacement, which used the traditional method.

With the new technology, patients undergo a CT scan prior to their surgery that essentially creates a map of their bones, muscles and tendons. Then, using that image, the robotic arm's computer determines where best to do the incision and ensures that the implant is aligned properly.

"With the computer, you can virtually manipulate where the implant will go. Basically, you can virtually complete the surgery before you perform any bone cuts," Nanson said. "Now we really have a three-dimensional idea of how we need to put the knee in for each patient."

According to Nanson, traditional knee replacements have resulted in an 80-85 percent patient satisfaction rate, with a small percentage of patients requiring second "revision" surgeries. A quarter of those revisions are necessary because the implant is unstable, something that Nanson says the new technology essentially eliminates.

Though the process requires an extra visit for the CT scan, 10-15 extra minutes of operating time and costs a few hundred extra dollars, Nanson said it's worth it to avoid a second surgery, which cost around $75,000 and 2-3 months' recovery time.

The robotic arm technology had been used for partial knee and full hip replacements, and builds on the traditional knee replacement process that's been used for the last 8 years. With the initial introduction in January and the full market rollout of the technology in March, Nanson has now done more than 70 knee replacements using the Mako system.