Interventional, multicentre investigation of a novel lumbar total joint replacement: propensity matched study design and protocol.

introductionThe study aims to demonstrate non-inferior clinical success (safety and efficacy) of the MOTUS Total Joint Replacement device relative to posterior or transforaminal lumbar interbody fusion with respect to a composite endpoint. The primary hypothesis for this study is that the probability of achieving 24-month composite clinical success (CCS) for subjects receiving the investigational device is not clinically inferior to the probability of achieving 24-month CCS for subjects receiving lumbar interbody fusion collected in a separate real-world evidence (RWE) study. METHODS AND ANALYSIS: This study is an interventional, multicentre (20 sites), prospective, non-blinded investigation of the MOTUS Total Joint Replacement device. The data collected in this study will be compared with a lumbar interbody fusion control group collected in an RWE study. The study design includes concurrently enrolled, non-randomised, investigational and control arms and features several elements intended to ensure comparability of subjects in the two groups. Sites were selected that would enrol both groups and represent a geographical mixture of urban and rural, teaching versus non-teaching institutions, surgical site status (ambulatory surgical centre vs hospital) and implanting surgeon specialty (neurological vs orthopaedic). Both groups were enrolled in overlapping time periods, ensuring consistency in the practice of medicine. The same postoperative protocol was applied to both groups. Covariate balance is ensured through the use of propensity score methods. The primary endpoint requires individual subject success, which is met when each subject achieves all of the following criteria at 24 months: (1) improvement of at least 15 points in Oswestry Disability Index score (out of 100) at 24 months compared with baseline; (2) maintenance or improvement in neurological status at 24 months compared with baseline; (3) no subsequent surgical intervention including revision, reoperation, removal or supplemental fixation at the index level and (4) absence of serious device-related adverse events. ETHICS AND DISSEMINATION: This clinical study is part of an Investigational Device Exemption (IDE) from an ongoing Premarket Approval (PMA) application to the US Food and Drug Administration (FDA). Both arms of the study have been reviewed and approved by an independent IRB (WCG IRB, tracking numbers 20222831 and 20211903). The study is being conducted in accordance with the Good Clinical Practice guidelines and other applicable regulatory requirements including but not limited to FDA Regulations (21 CFR 50, 54, 56 and 812), Department of Health and Human Services Regulations (45 CFR 46), ISO 14155 and the Declaration of Helsinki. Study results will be disseminated within the context of the PMA process and ClinicalTrials.gov, with the intent of publication in conferences and peer-reviewed literature. TRIAL REGISTRATION NUMBERS: NCT05438719; NCT04823858.