Purpose <p>Corticosteroid injections are commonly used to treat symptomatic knee osteoarthritis; however, pain relief is usually transient. Genicular artery embolization (GAE) has shown promise as an effective minimally invasive intervention to alleviate symptomatic knee osteoarthritis. The MOTION study is being conducted to compare outcomes following GAE versus corticosteroid injection.</p> Materials and Methods <p>This is an international, multicenter, randomized controlled investigational device exemption (IDE) study enrolling adults (≥ 21 years old) with symptomatic knee osteoarthritis (Kellgren–Lawrence grades 1–4) across ≥ 45 centers worldwide. Patients will be randomized 1:1 to receive GAE with Embosphere® Microspheres (Merit Medical Systems, Inc.) or corticosteroid injections. The primary efficacy measure is clinical success at 6 months, defined as ≥ 50% improvement in the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) Pain Subscale. The primary safety measure is the proportion of patients free from treatment-related safety event(s) through 6-month post-index procedure (GAE or corticosteroid injection). Following the 6-month visit, patients in either cohort who do not achieve clinical success may crossover to the other study arm. Additional study measures will assess safety and efficacy outcomes throughout the 24-month follow-up period. The target sample size is 264 (132 per arm) and is based on the number of patients needed to confirm superior efficacy of GAE versus corticosteroid injections and non-inferiority with respect to safety. The overall study power is &gt; 80%.</p> Discussion <p>Findings from the MOTION study are expected to provide information on the magnitude of the therapeutic benefits associated with GAE versus standard of care over 24 months.</p> Trial Registration <p>NCT05818150.</p> Graphical Abstract <p></p>