Transcatheter Arterial Embolization as a Treatment for Medial Knee Pain in Patients with Mild to Moderate Osteoarthritis

Osteoarthritis is a common cause of pain and disability. Mild to moderate knee osteoarthritis that is resistant to nonsurgical options and not severe enough to warrant joint replacement represents a challenge in its management. On the basis of the hypothesis that neovessels and accompanying nerves are possible sources of pain, previous work demonstrated that transcatheter arterial embolization for chronic painful conditions resulted in excellent pain relief. We hypothesized that transcatheter arterial embolization can relieve pain associated with knee osteoarthritis. Transcatheter arterial embolization for mild to moderate knee osteoarthritis using imipenem/cilastatin sodium or 75 mu m calibrated Embozene microspheres as an embolic agent has been performed in 11 and three patients, respectively. We assessed adverse events and changes in Western Ontario and McMaster University Osteoarthritis Index (WOMAC) scores. Abnormal neovessels were identified within soft tissue surrounding knee joint in all cases by arteriography. No major adverse events were related to the procedures. Transcatheter arterial embolization rapidly improved WOMAC pain scores from 12.2 +/- A 1.9 to 3.3 +/- A 2.1 at 1 month after the procedure, with further improvement at 4 months (1.7 +/- A 2.2) and WOMAC total scores from 47.3 +/- A 5.8 to 11.6 +/- A 5.4 at 1 month, and to 6.3 +/- A 6.0 at 4 months. These improvements were maintained in most cases at the final follow-up examination at a mean of 12 +/- A 5 months (range 4-19 months). Transcatheter arterial embolization for mild to moderate knee osteoarthritis was feasible, rapidly relieved resistant pain, and restored knee function.