Genicular Artery Embolization for Reducing Pain in Symptomatic Knee Osteoarthritis: A Pilot Randomized Sham-Controlled Study (SHAM-PAIN) is a NIH-NIAMS funded project designed to assess enrollment feasibility and detect any differences between GAE and a similar sham intervention in reducing KOA-related pain at 3 months as measured by the Knee injury and Osteoarthritis Outcome Score (KOOS) pain subscore. Additionally, this study aims to determine the magnitude of difference in pain response between GAE and sham to adequately power a larger, more definitive randomized sham-controlled trial (RCT). The influence of psychosocial and psychocognitive factors, changes in analgesic use, and conditions of knee joint cartilage and effusion will similarly be explored to determine their impacts on perceived pain response to GAE.

Inclusion Criteria:

• Patients aged 40-80
• Bilateral or unilateral knee pain attributed to osteoarthritis (treat the knee with greater pain-if equal, patient chooses)
• Grade 2-4 osteoarthritis on standing weight-bearing knee radiographs per the Kellgren-Lawrence grading scale
• Knee pain > 6 months, refractory to conservative non-operative management, and scored ≥ 4 on Visual Analog Scale (VAS) (e.g., rest, activity modification, weight control, bracing, supervised physical therapy, nonsteroidal anti-inflammatory drugs (NSAIDs), acetaminophen, oral opiates, intra-articular hyaluronic acid, PRP, stem cells, and/or oral/injectable corticosteroids)
• Refusal of intra-articular corticosteroid injection

Exclusion Criteria:

• Active malignancy
• Active infection of the affected knee
• Corticosteroid injection of the affected knee within 3 months of enrollment
• Rheumatoid arthritis or other seronegative arthropathy
• Previous surgery of the affected knee (e.g., meniscus repair, meniscectomy, anterior cruciate ligament (ACL)/posterior cruciate ligament (PCL) reconstruction, chondroplasty, microfracture, loose-body removal, synovectomy, lateral release, patellar/quadriceps tendon repair, total or partial knee replacement, osteotomy, cartilage transplant), except diagnostic arthroscopy
• Grade 0-1 osteoarthritis per Kellgren-Lawrence grading scale of the affected knee
• Pregnancy or expected pregnancy
• GFR < 60 mL/min/1.73 m²
• Anaphylactic reaction to iodinated contrast
• Moderate to severe pain in other ipsilateral lower-limb joints (ankle, hip) with VAS > 4
• Body weight > 400 lbs (unsafe for angiography)
• Peripheral arterial disease of the treated extremity (Rutherford Grade 2 or greater)
• Type 1 diabetes mellitus
• Long-acting corticosteroid use within 6 months (3 months for short-acting)
• History or other evidence of acute kidney injury (AKI)
• History of reaction to contrast media, bronchial asthma, or allergic disorders
• History of hypersensitivity to gadolinium-based contrast agents (GBCAs)
• Chronic widespread generalized pain >4 on VAS pain scale, including neuropathic pain
• Major depressive disorder within 2 years before screening
• Other severe psychiatric disorder (e.g., schizophrenia, bipolar disorder)
• Suicide attempt or suicidal behavior within 30 days before screening
• Diagnosis of fibromyalgia
• Considering total knee replacement in the next year
• Any other condition, unwillingness, or inability that, in the investigator's opinion, could jeopardize the subject's safety or protocol compliance

Will need to be considered on an individual basis given the desire to protect PHI