Robotic- and orthosensor-assisted versus manual (ROAM) total knee replacement: a study protocol for a randomised controlled trial.

Background: Robotic-arm-assisted knee arthroplasty allows for more accurate component positioning and alignment and is associated with better patient-reported outcomes compared to manually performed jig-based knee arthroplasty. However, what is not known is whether the addition of an intra-articular sensor (Verasense) to aid intraoperative balancing of the total knee replacement (TKR) offers improved functional outcomes for the patient. The purpose of this research is to compare the outcomes of patients undergoing a conventional manual knee replacement to those undergoing TKR using robotic-assisted surgery and the Verasense to optimise alignment and balance the knee joint, respectively, and assess the associated cost economics of such technology.

Methods And Analysis: This randomised controlled trial will include 90 patients with end-stage osteoarthritis of the knee undergoing primary TKR. Patients meeting the inclusion/exclusion criteria that consent to be in the study will be randomised at a ratio of 1:1 to either manual TKR (standard of care) or robotic-arm-assisted TKR with Verasense to aid balancing of the knee. The primary objective will be functional improvement at 6 months following surgery between the two groups. The secondary objectives are to compare changes in knee-specific function, joint awareness, patient expectation and fulfilment, satisfaction, pain, stiffness and functional ability, health-related quality of life, cost-effectiveness, and gait patterns between the two groups. Ethical approval was obtained by the Tyne & Wear South Research Ethics Committee, UK. The study is sponsored by the Newcastle Hospitals NHS Foundation Trust.

Discussion: This study will assess whether the improved accuracy of component positioning using the robotic-arm-assisted surgery and the Verasense to aid balancing of the TKR offers improved outcome relative to standard manual jig-based systems that are currently the standard of care. This will be assessed primarily according to knee-specific function, but several other measures will also be assessed including whether these are cost-effective interventions.

Trial Registration: International Standard Randomised Controlled Trial Number ISRCTN47889316 https://doi.org/10.1186/ISRCTN47889316 . Registered on 25 November 2019 DATE AND VERSION FOR PROTOCOL: ROAM Protocol V1.0 (13-12-2018).