Bipolar RFA Versus Phenol Neurolysis for Knee Osteoarthritis Pain

NCT07805161 | Completed

• 2 other identifiers: GEAH-ALGO-GENI-FEN-BRF-2025-02AES-EK1-2024-0046
• Study Type: interventional
• Target: 69
• Locations: 1 country
• Sites: 1

Brief Summary

This prospective observational comparative study evaluates the analgesic efficacy and safety of ultrasound-guided bipolar radiofrequency ablation (BPRFA) versus phenol chemical neurolysis (PCN) of the genicular nerves in patients with chronic knee osteoarthritis (gonarthrosis) refractory to conservative treatment. Patients with moderate-to-severe chronic knee pain who demonstrate significant pain relief following diagnostic genicular nerve block undergo either BPRFA or PCN targeting the superior medial, superior lateral, and inferior medial genicular nerves under ultrasound guidance. Pain intensity and functional outcomes are assessed using the Numeric Rating Scale (NRS) and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) at baseline and during follow-up evaluations at 4, 12, and 24 weeks after treatment. The study aims to compare pain reduction, functional improvement, responder rates, and procedure-related adverse events between the two treatment modalities.

Conditions

Gonarthrosis

Keywords

knee; gonarthrosis; radiofrequency ablation; phenol; ultrasound; genicular nerves

Outcome Measures

Primary Outcomes (1)

• Change in Pain Intensity

  Pain intensity was assessed using the Numeric Rating Scale (NRS). Changes in NRS scores from baseline were evaluated after ultrasound-guided bipolar radiofrequency ablation and phenol chemical neurolysis of the genicular nerves.

  Baseline, 4 weeks, 12 weeks, and 24 weeks

Secondary Outcomes (3)

• Functional improvement

  Baseline, 4 weeks, 12 weeks, and 24 weeks

• Proportion of Patients Achieving ≥50% Reduction in NRS Scores

  12 weeks and 24 weeks

• Procedure-related complications

  Up to 24 weeks

Study Arms (2)

Phenol Chemical Neurolysis

ACTIVE COMPARATOR

Patients undergo ultrasound-guided phenol chemical neurolysis of the superior medial, superior lateral, and inferior medial genicular nerves following a positive diagnostic genicular nerve block.

Procedure: Phenol Chemical Neurolysis

Bipolar Radiofrequency Ablation

ACTIVE COMPARATOR

Patients undergo ultrasound-guided bipolar radiofrequency ablation of the superior medial, superior lateral, and inferior medial genicular nerves following a positive diagnostic genicular nerve block.

Procedure: Ultrasound-Guided Bipolar Radiofrequency Ablation

Interventions

Phenol Chemical Neurolysis PROCEDURE

Ultrasound-guided phenol neurolysis was performed targeting the superior medial, superior lateral, and inferior medial genicular nerves. Following confirmation of needle placement, 2 mL of 8% phenol was injected around each targeted genicular nerve.

Phenol Chemical Neurolysis

Ultrasound-Guided Bipolar Radiofrequency Ablation PROCEDURE

Ultrasound-guided bipolar radiofrequency ablation was performed using two parallel radiofrequency cannulas placed within 1 cm of each other targeting the superior medial, superior lateral, and inferior medial genicular nerves. Radiofrequency ablation was applied at 80°C for 90 seconds following sensory and motor stimulation testing.

Bipolar Radiofrequency Ablation

Eligibility Criteria

• Age: 18 Years - 75 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Adults aged 18 to 75 years
• Unilateral moderate-to-severe knee pain due to gonarthrosis
• Numeric Rating Scale (NRS) score ≥6
• Knee pain lasting longer than 6 months
• Radiological diagnosis of knee osteoarthritis, Kellgren-Lawrence grade 2-4
• Failure of conservative treatments, including analgesic medications, physical therapy, or intra-articular injections
• At least 50% pain relief after diagnostic genicular nerve block
• Ability to provide written informed consent

You may not qualify if:

• Knee pain due to causes other than osteoarthritis, such as fracture, trauma, spinal disorder, or inflammatory arthritis
• Previous knee surgery
• Knee joint effusion detected on physical examination or ultrasound
• Cognitive impairment
• Hepatic or renal failure
• Severe psychiatric disorder
• Local or systemic infection
• Coagulopathy
• Current use of antiplatelet or anticoagulant therapy
• Presence of a pacemaker
• Intra-articular injection or interventional knee procedure within the previous 6 months

Sponsors & Collaborators

• Saglik Bilimleri Universitesi: lead

Study Sites (1)

University Of Health Sciences, Gulhane School Of Medicine, Department Of Algology

Ankara, Etlik, 06010, Turkey (Türkiye)

Location

MeSH Terms

Conditions

Osteoarthritis, Knee

Condition Hierarchy (Ancestors)

Osteoarthritis; Arthritis; Joint Diseases; Musculoskeletal Diseases; Rheumatic Diseases

Study Officials

• Alp Eren Celenlioglu, MD./Assoc. Prof.

  Department of Algology, University of Health Sciences Gulhane Training and Research Hospital, Ankara, Turkiye

  STUDY DIRECTOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: May 5, 2026
• First Posted: September 4, 2026
• Study Start: August 1, 2024
• Primary Completion: June 1, 2025
• Study Completion: June 1, 2025
• Last Updated: September 4, 2026

Record last verified: 2026-05

Data Sharing

• IPD Sharing: Will not share

Locations

TU (1)