GAUCHO - Trial Genicular Artery Embolization Using Imipenem/Cilastatin vs. Microsphere for Knee Osteoarthritis: A Randomized Controlled Trial.

Genicular artery embolization (GAE) has emerged as a treatment option to improve quality of life in patients suffering from moderate-to-severe pain refractory to conservative treatment of knee osteoarthritis, with encouraging results. This paper describes the study protocol of a single-center, double-blind, randomized controlled trial designed to evaluate and compare the safety and efficacy of GAE using imipenem/cilastatin vs. microspheres for the treatment of moderate-to-severe pain associated with knee osteoarthritis. We hypothesized that there will be no difference in safety and efficacy outcomes. The study received ethics approval of the institutional review board with number 4.364.391 / CAAE: 37590820.3.0000.5342 and is registered onto the Registro Brasileiro de Ensaios Clinicos (ReBEC), with number RBR-2h5rwgb. Technical success was defined as embolization of at least 1 feeding artery supplying the hyperemic synovium of the knee joint. Primary outcome: clinical success was defined as improvement in symptoms, 50% reduction in Western Ontario and McMaster Universities Osteoarthritis Index pain scores or an increase of at least 10 points in the Knee Injury and Osteoarthritis Outcome Score from baseline to 3 months of follow-up. Secondary outcome: radiological success was defined as significant improvement in the Whole-Organ Magnetic Resonance Imaging Score for knee synovitis considering the embolized areas at 12 months of follow-up after GAE and a reduction in the analgesia or other conservative therapies for knee pain used by the patient at 3 and 12 months of follow-up. Clinical assessments will be performed before GAE, during GAE and at hospital discharge (for Visual Analog Scale of pain), and at 30 days, 3 months, and 12 months after GAE.