Geniculate Artery Embolization for Knee Pain Secondary to Osteoarthritis (OA)

Randomized Placebo-Controlled Single Blinded Study of Geniculate Artery Embolization for Knee Pain Secondary to Osteoarthritis

Purpose: To evaluate embolization as a treatment for OA related knee pain versus placebo to demonstrate the actual effect of embolization on pain and disability. Participants: There will be 21 subjects enrolled over the age 40 with knee pain secondary to arthritis. Procedures (methods): This will be a single-blinded randomized-controlled study of GAE versus placebo in a small population with knee pain secondary to arthritis 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, 2 weeks, 1, 3, 6, & 12 months. An MRI may be performed after the 1-month visit.

This will be a single-blinded randomized-controlled study of GAE versus placebo in a small population with knee pain secondary to arthritis to determine safety and efficacy. After Institutional Review Board (IRB) approval of a written informed consent and over, approximately a 24 month duration, N=21 subjects will be recruited. Only subjects ≥ 40 years will be screened for study recruitment. Subjects will be randomized in a 2:1 ratio of GAE:Placebo and will be blinded from study treatment (see flow chart below). The placebo procedure will be a diagnostic angiogram of the knee, without embolization. Appropriate measures will be taken to ensure patients and nursing staff caring for the patient are blinded to assignment. Each patient will be told at the time of recruitment that they may be randomly assigned to sham, but if after 1 month they have not had symptom improvement, their assigned procedure would be revealed and, if they had undergone a sham procedure, they will be allowed to proceed with embolization. This second procedure should be shorter than a complete angiogram and embolization, as the detailed angiogram will not need to be repeated, and therefore both arms will have similar total radiation dose. 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, 2 weeks, 1, 3, 6, & 12 months. An MRI may be performed after the 1-month visit.

This will be a single-blinded randomized-controlled study of GAE versus placebo in a small population with knee pain secondary to arthritis to determine safety and efficacy. The placebo procedure will be a diagnostic angiogram of the knee, without embolization. Appropriate measures will be taken to ensure patients and nursing staff caring for the patient are blinded to assignment. Each patient will be told at the time of recruitment that they may be randomly assigned to sham, but if after 1 month they have not had symptom improvement, their assigned procedure would be revealed and, if they had undergone a sham procedure, they will be allowed to proceed with embolization.

If after 1 month patients see no improvement, they will be unblinded and crossover to receive the Geniculate Artery Embolization Procedure

Gel-Bead Microspheres will be used for geniculate artery embolization (GAE) in subjects with knee osteoarthritis.

Western Ontario and McMaster University Osteoarthritis Index (WOMAC) will be used to measure function. This is a score derived from a questionnaire in which the patient answers questions regarding rheumatic symptoms in the subcategories of pain (5 items), stiffness (2 items), and physical function (17 items). Individuals select the level of difficulty they have performing various tasks using a 5 point Likert scale (0=None, 1=Slightly, 3=Very, 4=Extremely). Then, results are scored with a total score (minimum 0; maximum 96). A higher score indicates more difficulty in each of the categories.

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". Pain will be assessed at each of the patient's follow-up visits and used to measure the change from baseline (prior to the GAE procedure). The investigators will use this to measure if the patient's pain level decreases.

Western Ontario and McMaster University Osteoarthritis Index (WOMAC) will be used to measure function. This is a score derived from a questionnaire in which the patient answers questions regarding rheumatic symptoms in the subcategories of pain (5 items), stiffness (2 items), and physical function (17 items). Individuals select the level of difficulty they have performing various tasks using a 5 point Likert scale (0=None, 1=Slightly, 3=Very, 4=Extremely). Then, results are scored with a total score (minimum 0; maximum 96). A higher score indicates more difficulty in each of the categories.

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". Pain will be assessed at each of the patient's follow-up visits and used to measure the change from baseline (prior to the GAE procedure). The investigators will use this to measure if the patient's pain level decreases.

Western Ontario and McMaster University Osteoarthritis Index (WOMAC) will be used to measure function. This is a score derived from a questionnaire in which the patient answers questions regarding rheumatic symptoms in the subcategories of pain (5 items), stiffness (2 items), and physical function (17 items). Individuals select the level of difficulty they have performing various tasks using a 5 point Likert scale (0=None, 1=Slightly, 3=Very, 4=Extremely). Then, results are scored with a total score (minimum 0; maximum 96). A higher score indicates more difficulty in each of the categories.

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". Pain will be assessed at each of the patient's follow-up visits and used to measure the change from baseline (prior to the GAE procedure). The investigators will use this to measure if the patient's pain level decreases.

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.

The number and description of complications, adverse events, or poor outcomes (such as no improvement in pain) that are secondary to the GAE procedure, which will be summarized using counts.

6 months following procedure for the "GAE Procedure" and "Crossover Arm" Arms/Groups and 1 month following procedure for the "Sham Procedure" Arm/Group

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 or estimated glomerular filtration rate (eGFR) <60 obtained within the past 30 days.