Patients will be asked to take part in this research study because they have mild-to-moderate knee osteoarthritis (OA) and were referred clinically for a procedure called Genicular Artery Embolization (GAE). Osteoarthritis is the most common form of arthritis. It occurs when the protective cartilage that cushions the ends of the bones wears down over time. The symptoms of OA include pain or aching, stiffness, decreased range of motion, and swelling. The purpose of this study is to evaluate the safety and effectiveness of GAE for the treatment of knee pain attributed to OA.

Research participants will be in this research study for about 3 years. The study includes a screening visit, GAE procedure, and six follow-up visits.

At the screening visit, a review of their medical history, demographics, and medications will be collected; physical examination will be completed; knee x-ray will be done; and two questionnaires on your knee pain will be administered. The GAE procedure will involve receiving sedation or medication to help them relax, lidocaine injected under the skin in the area of the body where catheters will be inserted into one of your arteries and then using x-ray, a catheter will be directed to the arteries supplying the lining of the knee. Then tiny microspheres will be injected into the artery to decrease the blood supply to this knee joint tissue.

The follow-up visits up to 12 months will include a focused physical examination of the treated knee, documentation of medications, and two questionnaires will be administered. The follow-up visits at year 2 and 3 will include documentation of medications and any new treatments for OA as well as completion of two questionnaires. Follow-up visits maybe conducted in clinic or remotely.

Inclusion Criteria:

• Age 40-80 years
• Mild-to-moderate knee OA as determined by radiographs demonstrating Kellgren- Lawrence grade 2-3
• Self-reported pain of at least 5/10 VAS questionnaire
• Failure of conservative therapy, such as pain medications, for at least 3 months
• Patient must understand and sign the informed consent
• Patient can comply with the proposed follow-up schedule
• Patient can follow the post-operative management

Exclusion Criteria:

• History of rheumatoid arthritis
• Renal insufficiency precluding angiography (GFR < 50 mL/min)
• Irreversible coagulopathy
• Previous knee arthroplasty on the intended knee
• Existing knee joint infection
• Kellgren-Lawrence grade 1 or 4
• Severe atherosclerosis as manifest by claudication and/or diminished peripheral pulses
• Life expectancy < 6 months
• Infectious arthritis
• Allergy to iodinated contrast resulting in anaphylaxis
• Pregnant or interested in becoming pregnant three months from the date of the GAE procedure
• Involved in litigation or worker's compensation claims