NCT05407610: COGENIUS

Comparison of Conventional and Cooled Radiofrequency of the Genicular Nerves in Patients With Chronic Knee Pain

Recruiting now NA Last updated 24 May 2023

What this trial tests

NA trial testing Conventional Radiofrequency ablation of the genicular nerves in Knee Osteoarthritis in 400 participants. Currently enrolling.

Timeline

7 July 2022

Primary endpoint
1 March 2025

1 September 2026

Quick facts

Lead sponsor	Ziekenhuis Oost-Limburg
Phase	NA
Status	Recruiting now
Study type	INTERVENTIONAL
Allocation	randomized
Design	parallel
Masking	double
Primary purpose	treatment
Enrollment	400
Start date	7 July 2022
Primary completion	1 March 2025
Estimated completion	1 September 2026
Sites	15 locations across Belgium, Netherlands

Drugs / interventions tested

• Conventional Radiofrequency ablation of the genicular nerves
• Cooled Radiofrequency ablation of the genicular nerves
• Sham procedure — full drug profile →

Conditions studied

• Knee Osteoarthritis — all drugs for Knee Osteoarthritis →
• Persistent Postsurgical Pain — all drugs for Persistent Postsurgical Pain →
• Chronic Knee Pain — all drugs for Chronic Knee Pain →

Sponsor

Ziekenhuis Oost-Limburg — full company profile →

Who can join

18 and older, any sex, with Knee Osteoarthritis or Persistent Postsurgical Pain. Patients with the condition only — healthy volunteers not accepted.

Sponsor's own description

Chronic knee pain remains a disabling disease despite current treatment strategies. There is an increase in the prevalence of osteoarthritis (OA) of the knee in the general population, presently affecting approximately 450,000 individuals in Belgium. A total knee replacement is a viable alternative for severe knee OA that does not respond to conservative therapy. Unfortunately, up to 53% of patients who undergo a total knee replacement develop persistent post-surgical pain (PPSP). There is currently no effective therapy for PPSP.

A radiofrequency (RF) treatment applies high frequency current on the nerve responsible for pain conduction, resulting in an interruption of the transmission of pain. This can be applied to the nerves innervating the knee joint - the superolateral, superomedial and inferomedial genicular nerves - and could be an alternative, minimally invasive treatment for patients with knee OA who fail conservative treatments and for patients with PPSP. Data from the recent literature indicates that this treatment leads to a reduction of pain intensity and could result in an improvement of knee function, of the psychological state of the individual, and finally in an increase in health-related quality of life. Furthermore, RF of the genicular nerves could help avoid or delay a total knee replacement therefore potentially contributing to cost reduction. Both cooled and conventional RF treatments are reported in the literature to improve pain. The use of water to cool the RF electrodes results in an increased lesion size by removing heat from adjacent tissue, allowing power delivery to be increased. As a consequence, cooled RF could result in a higher chance of success and longer duration of effect. Until now, the studies performed on cooled RF are industry initiated and a direct comparison between conventional, cooled and a sham procedure is lacking.

The aim of the COGENIUS trial is to investigate the effect of the two types of RF treatment on individuals experiencing chronic knee pain that is resistant to conservative treatments. For this purpose, the efficacy and cost-effectiveness of cooled and conventional RF will be compared to a sham procedure in patients suffering from knee OA and PPSP after total knee replacement.

Publications & conference data

3 peer-reviewed publications reference this trial (live from Europe PMC):

1. Cooled versus conventional radiofrequency treatment of the genicular nerves for chronic knee pain: 12-month and cost-effectiveness results from the multicenter COCOGEN trial.
   Belba A, Vanneste T, Kallewaard JW, van Kuijk SM, et al · · 2025 · cited 9× · PMID 38388017 · DOI 10.1136/rapm-2023-105127
2. Comparison of conventional and cooled radiofrequency treatment of the genicular nerves versus sham procedure for patients with chronic knee pain: protocol for a multicentre, double-blind, randomised controlled trial (COGENIUS).
   Vanneste T, Belba A, van Kuijk S, Kimman M, et al · · 2023 · cited 6× · PMID 37532482 · DOI 10.1136/bmjopen-2023-073949
3. Genicular nerve radiofrequency ablation: proposal of a technical protocol for managing procedural pain.
   Rocha-Romero A, Ng TKT, Ferreira-Dos-Santos G. · · 2025 · PMID 39743320 · DOI 10.3344/kjp.24312