Robot knee surgery more accurate

A randomised control trial by Imperial College London has shown that robot assisted knee surgery is more accurate, if slightly slower, than conventional surgery.

The team of surgeons tested whether Acrobot, a robotic assistant, could improve surgical outcomes for patients undergoing partial knee replacement. Acrobot (Active Constraint Robot) works by helping the surgeon to line up the replacement knee parts with the existing bones. It reacts to the actions of the surgeon and restricts motion to within a predefined volume.

The surgeons looked at 27 patients undergoing unicompartmental knee replacement. The patients were separated into two groups as part of a randomised controlled trial, with 14 having conventional surgery, and the remaining 13 having robot assisted surgery.

Although the operations took a few minutes longer using the robotic assistant, the replacement knee parts were more accurately lined up than in conventional surgery. All of the robotically assisted operations lined up the bones to within two degrees of the planned position, but only 40 percent of the conventionally performed cases achieved this level of accuracy.

The team found there were no additional side effects from using robot-assisted surgery, and recovery from surgery was quicker in most cases.

The study involved both surgeons and engineers from Imperial College, with medical robotics engineers designing the Acrobot prototype, and surgeons testing it.