Purpose: Genicular artery embolization (GAE) is a promising therapy to treat patients with symptomatic knee osteoarthritis (OA) by reducing synovial arterial hypervascularity. This study evaluates the safety and efficacy of GAE for the treatment of symptomatic knee OA.
Materials and Methods: A prospective, single-center, open-label FDA-approved IDE study was conducted to evaluate the safety and efficacy of GAE for the treatment of symptomatic knee OA. Included patients were age 40-80 years, with moderate or severe focal knee pain and osteoarthritis on knee radiograph (Kellgren-Lawrence 2-4), had no prior knee surgery, and were not candidates or not willing to undergo total knee replacement surgery. Patients had to have failed conservative therapy, including NSAIDs and/or joint injections. Baseline pain (visual analog scale) and symptom scores (WOMAC) were assessed. Median age was 69 years (range 49-80). Median BMI was 28 (range 18-44). Knee OA severity based on Kellgren-Lawrence scale: 18% with grade 2, 43% with grade 3, and 40% with grade 4. After obtaining femoral arterial access, genicular artery embolization was performed using 100 μm particles (Embozene, Varian) of 1-3 genicular arteries supplying the location of the subject's pain, as determined by digital subtraction angiography and cone-beam CT. Adverse events and symptoms scores were assessed at 1 week, 1 month, 3 months, 6 months, and 1 year after GAE.
Results: Over a 9-month period, 40 patients were treated with GAE. The left knee was treated in 25/40 (62%) subjects, and the right knee was treated in 15/40 (38%) subjects. Medial knee pain was treated in 27/40 (68%) and lateral knee pain was treated in 13/40 (32%). Technical success was achieved in 100% of subjects. Transient skin discoloration and transient mild post-procedure knee pain were common and expected. Treatment-related adverse events included: 1 subject with a groin hematoma requiring overnight observation, 7 subjects with self-resolving focal skin ulceration, and 2 subjects with asymptomatic small bone infarct on MRI at 3 months. WOMAC and pain scores decreased from median of 52 (out of 96) and 8/10 at baseline to 21/96 (60% decrease) and 3/10 (63% decrease) at 12 months, respectively. 27/40 (67.5%) and 28/40 (70%) had greater than 50% reduction in WOMAC and pain scores, respectively.
Conclusion: This prospective trial demonstrates that GAE is highly effective and durable in reducing symptoms due to moderate to severe knee OA that is refractory to other conservative therapy, and has an acceptably low toxicity profile.