Recruiting

Fluoroscopic vs. Ultrasound

Sponsor:

UCLA

Code:

NCT04472702

Conditions

Knee Osteoarthritis

Eligibility Criteria

Sex: All

Age: 35 - 70+

Healthy Volunteers: Not accepted

Interventions

cRFA

Study Details

Brief summary:

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.

Conditions

Knee Osteoarthritis

Study ID

NCT04472702

Start date

Feb 2, 2022

Status verified date

Jun, 2026

Completion date

May 1, 2027

Anticipated

Primary completion date

May 1, 2027

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 35 - 70+

Healthy Volunteers: Not accepted

Inclusion Criteria:

  • 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.

Exclusion Criteria:

  • 1\) age <35 years,
  • 2\) non-English speaking patients,
  • 3\) body mass index greater than 40,
  • 4\) previous radiofrequency ablation procedure for the knee,
  • 5\) active systemic or local infections at the site of needle/cRFA probe placement,
  • 6\) previous knee joint replacement surgery,
  • 7\) autoimmune or inflammatory cause of knee arthritis such as rheumatoid or psoriatic arthritis,
  • 8\) non-ambulatory patients,
  • 9\) patients who are unable to provide their own consent (e.g. dementia),
  • 10\) unstable medical or psychiatric illness,
  • 11\) patients with pacemakers, spinal cord stimulators, deep brain stimulators, or similar devices,
  • 12\) patients seeking care as a part of workman's compensation or have litigation pending
  • 13\) a negative response to diagnostic geniculate nerve lidocaine injections.

Study Design

Enrollment

90 participants

Anticipated

Allocation

Randomized

Intervention Model

Parallel Assignment

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

experimental: Subjects with knee OA using ultrasound for cRFA intervention

Knee osteoarthritis patients (Kellegren-Lawrence Scale 2-4) that have been refractory to conservative treatments and report at least 80% pain relief with diagnostic geniculate nerve blocks will be enrolled and randomized to ultrasound (N=45) cRFA treatment arm.

experimental: Subjects with knee OA using fluoroscopy for cRFA intervention

Knee osteoarthritis patients (Kellegren-Lawrence Scale 2-4) that have been refractory to conservative treatments and report at least 80% pain relief with diagnostic geniculate nerve blocks will be enrolled and randomized to fluoroscopic (N=45) cRFA treatment arm.

Interventions

cRFA

cRFA 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.

Primary outcome measure

  • Numeric Pain Rating Scale [ Time Frame: Baseline up to 24 months ]
  • Western Ontario and McMaster Universities Arthritis Index (WOMAC) [ Time Frame: Baseline up to 24 months ]
  • PROMIS - Depression [ Time Frame: Baseline up to 24 months ]
  • PROMIS - Pain Interference [ Time Frame: Baseline up to 24 months ]

Central Contacts and Locations

Central contacts

Daniel Herman, MD

916-734-6805dcherman@ucdavis.edu

Katherine Rizzone, MD

585-341-9407katherine_rizzone@urmc.rochester.edu

Locations

University of Rochester

Recruiting

Rochester, New York, United States, 14627

Contacts

Katherine Rizzone, MD

585-341-9407katherine_rizzone@urmc.rochester.edu

Principal Investigator:

Katherine Rizzone, MD

More Information

Sponsor

University of California, Davis

Last update posted

Jun 16, 2026

Last verified

Jun, 2026

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by University of California, Davis on 2026-06-16.