• Posted August 25, 2026

Robot-Assisted Knee Replacement Surgery No Better Than Traditional Surgeon-Only Procedures, Trial Finds

Knee replacement patients do just as well with regular old “sawbones” surgery as they do with cutting-edge robot-assisted procedures, a new clinical trial has found.

Robot-assisted knee replacement surgery is more precise than a surgeon on their own, but does not currently lead to better patient outcomes, researchers reported Aug. 20 in The Lancet.

Patients treated either way had similar recovery, mobility and pain levels one year after surgery, researchers found.

These results come from the largest-ever clinical trial comparing new robotics techniques against traditional knee surgery, researchers said.

“The trial demonstrates robotic-arm-assistance allows for higher precision, and in theory the system should allow surgeons to customize the procedure according to a patient’s anatomy,” senior researcher Dr. Edward Davis said in a news release. He’s a consultant orthopedic surgeon at the Royal Orthopedic Hospital NHS Foundation Trust in the U.K.

“These results are by no means a condemnation of the robotic systems, but more understanding of the ideal position for a knee replacement and personalization for each patient is needed,” Davis said. “We’ll then be able to truly take advantage of the advanced precision of robotic systems.”

Robotic assistance is increasingly being used in knee replacement surgeries, accounting for 16% of such procedures in the United States and 41% in Australia, researchers said in background notes.

Surgeons typically rely on their experience and a standard set of instruments to perform knee replacements, researchers said.

The newer technique relies on a robotic arm that can position instruments with high precision and provide surgeons with greater flexibility to vary cutting angles and depths. Theoretically, this should allow doctors to tailor a knee replacement more precisely to a patient’s individual anatomy in ways conventional surgery can’t, researchers said.

For the new trial, researchers recruited 339 patients being treated by 33 surgeons at 10 hospitals across the U.K., and randomly assigned them to either surgeon-only or robot-assisted knee replacement surgery.

Robot surgeries took longer to perform, just under 11 minutes more, and were about $1,300 more expensive, researchers said. They also were more precise and weren’t associated with an increased risk of serious side effects, suggesting robots are as safe as conventional surgery.

“Technology such as this could really help the care we give for patients, but for robotic-assisted knee replacements, there is still work to do before we see benefits such as less pain or better movement,” researcher Dr. Andrew Metcalfe, a professor at the University of Warwick Medical School in the U.K., said in a news release.

More information

Penn Medicine has more on robotic knee replacement surgery.

SOURCES: University of Warwick, news release, Aug. 21, 2026; The Lancet, Aug. 20, 2026