Cooled radiofrequency ablation (cRFA) of the knee geniculate nerves is a promising treatment option for knee osteoarthritis, but has variable efficacy. Fluoroscopy is the typical guidance of choice, but uses bony landmarks to target these nerves which have variable positions around the knee. Alternatively, ultrasound allows for targeting based on visualization of bony landmarks, the nerves, and their accompanying vascular structures, and thus may offer greater accuracy. However, there are few studies which directly compare the clinical efficacy of these two guidance options. This study will compare these two options.
1) patients of either gender with primary knee OA of one or both knees fulfilling the diagnostic criteria for knee OA by the American College of Rheumatology,
2) Kellgren-Lawrence score of two to four,
3) reported NPRS pain intensity of at least four on most or all days of the past week
4) pain resistant to conventional treatments which may include but is not limited to medications (e.g. acetaminophen, oral or topical non-steroidal anti-inflammatory drugs, opioids), physical therapy, and intra-articular injections (e.g. corticosteroids, hyaluronic acid, platelet-rich-plasma) for at least 3 months. In the case of bilateral knee OA, the most symptomatic knee will be treated and studied.
1) age <35 years,
2) non-English speaking patients,
3) body mass index greater than 40,
4) previous radiofrequency ablation procedure for the knee,
Parallel
cRFA
Procedure/SurgerycRFA intervention will occur under sterile conditions, the patient will be placed in a supine position on a table and a bolster to provide flexion in the treated knee joint. Skin and soft tissues will be anaesthetized with 2 mL 1% lidocaine at each of the three anatomic sites for cRFA, and a introducer needle will then be placed under ultrasound or fluoroscopic guidance to the SLG, SMG, and IMG nerves. Adjustments at these positions will be made when using ultrasound guidance in order to capture the geniculate nerve if the nerve and/or its accompanying vasculature can be directly visualized using greyscale or Doppler modes. When using ultrasound, the physician will note and record whether their positioning of the needle is based on bony landmarks, direct visualization of the nerve, and/or vascularity accompanying the nerve. Once the introducer needle is placed, the cRFA will be placed into the introducer needle.
Numeric Pain Rating Scale
The objective is to rate patient's reported pain. The NPRS asks for a number between zero and ten that fits best to the subject's pain intensity, with zero as "no pain at all" and ten representing "the worst pain ever possible". It has a similar minimal clinically significant difference (20%) as the visual analog scale and can be administered via a phone interview.
Western Ontario and McMaster Universities Arthritis Index (WOMAC)
The objective is to measure the patient's reported functional status.The test questions are scored on a scale of 0-4, which correspond to: None (0), Mild (1), Moderate (2), Severe (3), and Extreme (4). The scores for each subscale are summed up, with a possible score range of 0-20 for Pain, 0-8 for Stiffness, and 0-68 for Physical Function. Usually a sum of the scores for all three subscales gives a total WOMAC score, however there are other methods that have been used to combine scores
PROMIS - Depression
The objective is to measure items relevant to the subject's mood, views of self, and engagement. The test version 8b has good responsiveness with a minimally important difference range of 3-3.1 in adults with knee OA.
PROMIS - Pain Interference
The objective is to measure the consequences of pain on the subject's life with a minimally important difference range of 2.35 to 2.4
30-Second Chair Stand Test
The objective is to determine the maximum number of chair stand repetitions possible in a 30 second period.
Stair Climb Test
The objective is to determine the time (seconds) it takes to ascend and descend a flight of stairs.
40m Fast Paced Walk Test
The objective is to determine the time (seconds) it takes to complete a fast-paced walking task over 4x10m (total 40m).
Timed Up and Go Test48
The objective is to determine the time (seconds) to rise from a chair, walk 3m, turn, walk back to the chair, and then sit down.
Click on the lead sponsor to view all of their trials.
University of California, Davis
Lead sponsor
American Medical Society for Sports Medicine
Collaborator
