What is knee osteoarthritis?
Osteoarthritis is a whole-joint degenerative process. Cartilage thins, subchondral bone remodels, osteophytes can develop, and the synovial lining may become chronically inflamed. Typical symptoms include activity-related pain, stiffness, swelling, and progressive difficulty walking or climbing stairs.
Why osteoarthritis hurts
Knee osteoarthritis is not simply loss of cartilage. Chronic synovitis, inflammatory mediators, subchondral changes, and abnormal small-vessel growth can contribute to pain. In some patients, angiography demonstrates hypervascularity that corresponds to the painful region of the knee.
Who may be a candidate?
GAE is generally considered after appropriate conservative care has not provided sufficient relief. Evaluation should confirm that symptoms truly arise from osteoarthritis rather than lumbar radiculopathy, hip disease, inflammatory arthritis, meniscal pathology, infection, or another cause. Patients who are not ready for knee replacement, are poor surgical candidates, or want to delay arthroplasty may be particularly interested in GAE.
How the procedure works
Through a small arterial access site, a microcatheter is navigated into selected genicular arterial branches. Angiography is used to identify abnormal hypervascularity around the painful synovium. Small embolic particles are delivered selectively to reduce this pathologic vascular response while preserving normal arterial supply.
Evidence and where GAE fits
In 2026, the Society of Interventional Radiology published a position statement supporting GAE as a viable minimally invasive treatment option for appropriately selected patients with symptomatic knee osteoarthritis who have failed conservative therapy and are not candidates for, or wish to delay, total knee arthroplasty. SIR also emphasized the importance of trained operators and multidisciplinary care.
Recovery and risks
GAE is usually performed as an outpatient procedure. Patients may experience temporary bruising, soreness, or skin discoloration. Less common risks include arterial injury, nontarget embolization, access-site complications, and other vascular complications. GAE does not reverse established cartilage loss and does not prevent future knee replacement if arthritis progresses.
Procedure Video
See genicular artery embolization
Patient-focused GAE explanation from Brigham and Women's Hospital. Third-party educational video; technique and equipment vary.