Geniculate Artery Embolization for the Treatment of Knee Pain (GAE)

This study is to test a new treatment method, geniculate artery embolization (GAE), to reduce the severity of pain and disability caused by knee osteoarthritis.

Purpose: The primary aims of this study are to determine if geniculate artery embolization (GAE) will reduce the severity of pain as well as global disability (resulting from the combination of pain, stiffness and difficulty performing daily activities) caused by knee OA and if it can be performed safely. The secondary aim is to determine if GAE can result in the decreased necessity for ongoing conservative OA therapies such as medication therapy and joint injections. Participants: Twenty patients with knee osteoarthritis resulting in knee pain that is refractory to conservative therapies, who are not planning to undergo surgery within 6 months. Procedures (methods): This will be an open label 24-month pilot study with a small population undergoing GAE to determine safety and efficacy. Clinical procedures and evaluations will consist of a preoperative screening assessment to determine if the potential study subject meets the inclusion and exclusion criteria, enrollment, surgical procedure for geniculate artery embolization, and follow-up visits at 24 hours, 1, 3 & 6 months. An MRI will be performed at the 1-month visit to detect a change in synovial vascularity and to exclude complication.

Patients in this study will receive the geniculate artery embolization (GAE) procedure. The primary aims will be to determine if geniculate artery embolization (GAE) will reduce pain and disability (resulting from pain, stiffness and difficulty performing daily activities) caused by knee osteoarthritis (OA).

Geniculate artery embolization (GAE) is a new procedure that is being used to reduce pain and disability (resulting from pain, stiffness and difficulty performing daily activities) caused by knee osteoarthritis (OA). Embolization is a procedure where physicians intentionally block the blood vessels to specific areas of the body to prevent blood flow to that region. By doing this, the decrease in blood flow will decrease the size of the area of interest. In this case, the goal is to decrease the size of inflammatory tissue around the knee, resulting in improvement of pain, stiffness and difficulty performing daily activities from OA.

Western Ontario and McMaster University Osteoarthritis Index will be used to measure function. This is a score derived from a questionnaire in which the patient answers questions regarding rheumatic symptoms, stiffness, pain and how it affects the ability to function. Participants are asked to rate each question on a scale from 0 to 4 (0 = None, 1 = Slight, 2 = Moderate, 3 = Very, 4 = Extremely) for the level of difficulty to complete each task. The categories are then totaled for an overall score out of 96. Higher values indicate greater levels of pain, stiffness, and functional limitations.

The pain intensity is assessed using a visual analogue scale (VAS), which is a horizontal line 100 mm in length. Subjects mark the VAS with a single vertical line to indicate their current pain level, with 0 mm representing "No Pain" and 100 mm representing "Worst Possible Pain".

Reduction in Medication (Percentage of Participants With a Reduction in Medication Therapy at Month 6)

Reduction in the number or strength of previously initiated OA medical therapy (e.g. NSAIDs) at 6 months follow-up, which will be summarized using counts and simple statistics (percentage of participants with a reduction in medication therapy at month 6 months).

The number and description of complications, adverse events, or poor outcomes that are secondary to the GAE procedure, which will be summarized using counts and simple statistics (number of participants with complications at month 6)

Inclusion Criteria: Moderate to severe knee pain (visual analog scale (VAS) > 50 mm), and Pain refractory to at least 3 months* of conservative therapies (anti-inflammatory drugs, or physical therapy, or muscle strengthening, or intra-articular injections), and Kellgren-Lawrence grade 1, 2 or 3 on radiograph of the knee. Exclusion Criteria: Current local infection, or Life expectancy less than 6 months, or Known advanced atherosclerosis, or Rheumatoid or infectious arthritis, or Prior knee surgery, or Uncorrectable coagulopathy including international normalized ratio (INR) > 2.5 or platelets < 30,000, or Iodine allergy resulting in anaphylaxis, or Renal dysfunction as defined by serum creatinine >1.6 dl/mg obtained within the past 30 days.