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

Abstract

Purpose 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. Methods Transcatheter arterial embolization for mild to moderate knee osteoarthritis using imipenem/cilastatin sodium or 75 lm 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. Results 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 ± 1.9 to 3.3 ± 2.1 at 1 month after the procedure, with further improvement at 4 months (1.7 ± 2.2) and WOMAC total scores from 47.3 ± 5.8 to 11.6 ± 5.4 at 1 month, and to 6.3 ± 6.0 at 4 months. These improvements were maintained in most cases at the final follow-up examination at a mean of 12 ± 5 months (range 4-19 months). Conclusion Transcatheter arterial embolization for mild to moderate knee osteoarthritis was feasible, rapidly relieved resistant pain, and restored knee function.

Protocol for a single-centre, parallel-arm, randomised controlled superiority trial evaluating the effects of transcatheter arterial embolisation of abnormal knee neovasculature on pain, function and quality of life in people with knee osteoarthritis

“…The sample size was calculated on the basis of the primary outcome. Using data provided by Okuno et al , 6 we estimated that the SD of change in pain 12 months post intervention was 19.9%. Given the small sample size and the observational nature of Okuno et al ’s study, we chose a conservative approach and used the upper limit of the 80% CI for the SD.…”

“… 3–5 Treatment seeks to manage symptoms, but adequate symptom control can be difficult to achieve. 6 Core evidence-based treatment options for knee OA include intra-articular corticosteroids, exercise (land based and water based), education, weight management, and oral medications such as paracetamol and non-steroidal anti-inflammatories. 7 Joint replacement is generally reserved for those with severe joint disease, pain and functional limitations.…”

“… 10 11 Okuno et al investigated the effects of embolising abnormal blood vessels about the knee on pain in people with mild to moderate knee OA. 6 Fourteen participants received transcatheter arterial embolisation of abnormal branches of the genicular artery using imipenem and cilastatin sodium or 75 µm Embozene microsphere. WOMAC (Western Ontario and McMaster Universities Osteoarthritis Index) pain and function scores improved substantially at 1, 4 and 12 months post procedure.…”

“…The current study seeks to elaborate on Okuno et al ’s single-arm trial 6 by using a randomised controlled design with a larger cohort of people.…”

Embolization for Osteoarthritic Pain: Ready to Cross the Chasm?

“…In April 2015, a publication by Yuji Okuno and colleagues ignited interest among the global Interventional Radiology community, with the description of a novel endovascular treatment for osteoarthritic knee pain. 1 The premise of the technique is the embolization of abnormal synovial neo-vessels which arise from the genicular arteries of the knee as a consequence of chronic inflammation. The hypothesis is that these neo-vessels are associated with perivascular nerve fibers which result in pain; blocking these neo-vessels is, therefore, a potential target for symptom relief in this patient group.…”