Hands-on robotic unicompartmental knee replacement

TLDR

In a prospective randomized trial of 27 patients undergoing unicompartmental knee arthroplasty, surgeons used either the Acrobot robotic system or conventional techniques, with tibiofemoral alignment measured by CT as the primary outcome and additional secondary parameters recorded. All Acrobot‑assisted knees achieved tibiofemoral alignment within 2° of the planned position, compared with only 40% of conventional cases, and although operative time was longer, no adverse events occurred and there was a trend toward better functional scores at six weeks and three months, indicating that the Acrobot improves reproducibility of the surgical plan.

Abstract

We performed a prospective, randomised controlled trial of unicompartmental knee arthroplasty comparing the performance of the Acrobot system with conventional surgery. A total of 27 patients (28 knees) awaiting unicompartmental knee arthroplasty were randomly allocated to have the operation performed conventionally or with the assistance of the Acrobot. The primary outcome measurement was the angle of tibiofemoral alignment in the coronal plane, measured by CT. Other secondary parameters were evaluated and are reported. All of the Acrobot group had tibiofemoral alignment in the coronal plane within 2° of the planned position, while only 40% of the conventional group achieved this level of accuracy. While the operations took longer, no adverse effects were noted, and there was a trend towards improvement in performance with increasing accuracy based on the Western Ontario and McMaster Universities Osteoarthritis Index and American Knee Society scores at six weeks and three months. The Acrobot device allows the surgeon to reproduce a pre-operative plan more reliably than is possible using conventional techniques which may have clinical advantages.