Minimally Invasive Procedure Halves Knee Osteoarthritis Pain After One Year, Study Finds

Knee osteoarthritis is the most common form of arthritis and a leading cause of disability worldwide. It occurs when the protective cartilage within the joint gradually breaks down, triggering pain, stiffness, and reduced mobility that can significantly affect everyday life.

Many patients rely on physiotherapy, painkillers, or anti-inflammatory injections, but these treatments often become less effective over time. For some, the only remaining option is total knee replacement surgery, which carries surgical risks and requires a lengthy recovery.

New minimally invasive treatment

A research team from Charité – Universitätsmedizin Berlin has reported promising results from a minimally invasive procedure called genicular artery embolization (GAE). The technique aims to interrupt the cycle of inflammation and pain associated with knee osteoarthritis.

GAE targets abnormal blood vessels and the accompanying growth of pain-sensing nerves that develop around damaged joints. By selectively blocking these vessels, physicians hope to reduce inflammation without compromising the overall blood supply to the knee.

How dissolving microspheres work

In the new study, doctors used tiny resorbable gelatin microspheres as the embolic material. These microscopic gelatin beads are delivered through a catheter into the arteries supplying the affected region of the knee.

The beads temporarily block abnormal blood vessels associated with inflammation and pain. Unlike older embolic agents based on antibiotics, the microspheres dissolve within hours in the bloodstream, reducing concerns about long-term vessel occlusion and antibiotic resistance.

Lead radiologist Florian Nima Fleckenstein said the goal is to restore a more normal vascular and nerve environment within the joint. By reducing these abnormal changes, the team believes the procedure may not only relieve symptoms but also slow the progression of osteoarthritis.

Pain levels halved after one year

The observational study included 194 patients with knee osteoarthritis who had not responded to previous treatments. Participants had a mean age of 69 years and continued to experience persistent pain despite physiotherapy, anti-inflammatory medication, or injections.

Before undergoing the procedure, participants rated their average pain intensity as 7 out of 10. Twelve months after GAE with resorbable microspheres, the average pain score had fallen to 3 out of 10, indicating a substantial and sustained reduction in pain.

Patients also reported significant improvements in daily activities, participation in sports and recreational activities, and overall quality of life. According to the researchers, the procedure required no prolonged hospital stay and was not associated with any significant adverse effects.

A potential new option between injections and surgery

Fleckenstein emphasized that the study was designed to reflect routine clinical practice rather than a narrowly selected clinical trial population. The participants closely resembled patients typically treated in orthopedic and interventional radiology clinics.

The researchers suggest that, for appropriately selected patients, GAE could provide long-lasting symptom relief through a single minimally invasive procedure. It may fill an important treatment gap for people who no longer benefit from injections but are not yet ready or suitable candidates for joint replacement surgery.

However, the study did not include a control group for direct comparison, and all participants were treated at a single medical center. Experts note that larger randomized clinical trials will be needed to determine how GAE compares with existing treatments or placebo procedures.

Next steps in osteoarthritis care

The findings contribute to a growing body of research into non-surgical treatments for knee osteoarthritis. Other experimental approaches include advanced cartilage-mimicking hydrogels, regenerative therapies, and improved targeted pain-management techniques.

Researchers say long-term follow-up will be essential to determine whether GAE can alter the long-term progression of osteoarthritis rather than simply relieve symptoms. Studies extending beyond 12 months and involving more diverse patient populations are now needed.

Although important questions remain, the Berlin study offers cautious optimism for patients caught between conservative treatment and major surgery. If future clinical trials confirm these findings, genicular artery embolization using dissolving microspheres could become a valuable addition to the treatment options available for knee osteoarthritis.