Clinical and radiological outcomes of robotic-assisted unicompartmental knee arthroplasty: Early lessons from the first 100 consecutive knees in 85 patients

Abstract

Introduction: Robotic-assisted unicompartmental knee arthroplasty (UKA) is associated with improved component positioning and comparable short- and mid-term implant survivorship with manual UKA. This study aims to evaluate clinical and radiological outcomes following robotic-assisted UKA as well as any potential learning-curves associated with the introduction of such new technology.

Methods: Prospective study of patients undergoing robotic-assisted UKA. Outcome measures were patient-reported outcome measures (PROMs) including Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Knee Society Score (KSS) and Oxford Knee Score (OKS), complications, implant survivorship, component positioning and learning curve.

Results: Eighty-five patients comprising 100 knees were recruited and followed up for 21.0 ± 4.3 months. At two years, there were significant and sustained improvements in PROMs and 100% implant survivorship rate. A high degree of implant accuracy was achieved with the robotic system. A cumulative learning curve of 20 cases was noted.

Conclusion: Robotic-assisted UKA achieves excellent implant accuracy and clinical outcomes in the short-term. Long-term follow up is needed to evaluate this relationship.

Keywords: Component positioning; Mako; Patient-reported outcome measures; Robotic-assisted; Survivorship; Unicompartmental knee arthroplasty.