1. 2025;28;E233-E242Comparison of Radiation Exposure Between Trident and Conventional Cannula in Genicular RF Procedures Under Fluoroscopy for Gonarthrosis
   Observational Study
   Ahmet Yilmaz, MD.

BACKGROUND: Genicular nerve radiofrequency ablation (GNRFA), including conventional, cooled, and pulsed techniques, has been used in the treatment of symptomatic knee osteoarthritis (OA).

OBJECTIVES: This study aimed to compare conventional and trident GNRFA application methods, to evaluate the characteristics of fluoroscopy use and to evaluate the differences in terms of x-ray exposure.

STUDY DESIGN: Observational study and original research.

SETTING: This work was conducted at Adana City Hospital, Adana, Turkey.

METHODS: A 3-pronged radiofrequency ablation (RFA) cannula was pushed under C-arm fluoroscopic guidance to known sites of the superomedial genicular nerve, superolateral genicular nerve, inferomedial genicular nerve, nerve to vastus medialis, nerve to vastus lateralis and nerve to vastus intermedius shortly after suitable placement, sterile preparation, and subcutaneous anaesthesia. All patients were exposed to ablation at RF 90°C for 60 seconds.

RESULTS: The study included 41 patients, 28 (68.3%) women and 13 (31.7%) men, with a mean age of 68.2 ± 7.0 years. Conventional and Trident™ GNRFA was performed in 22 and 19 patients, respectively. The median radioactivity exposure in the conventional GNRFA group was 0.14 (0.11/0.17) mGy, while the median radioactivity exposure in the Trident™ group was 0.11 (0.06/0.17) (P < 0.001). WOMAC scores between the baseline and first- and third-month post-treatment in the Trident™ group were significantly higher than in the conventional group (P = 0.018 and P = 0.006, respectively). In both treatment groups, the improvement in VAS and WOMAC scores was significant at one month and continued similarly at 3 months.

LIMITATION: The study’s limitations include a small sample size and a lack of blinding due to the study design, which may have introduced bias.

CONCLUSION: GNRFA using a lateral approach and a Trident™ cannula offers significant advantages, including better improvement in WOMAC scores, shorter procedure times, fewer fluoroscopy shots, and reduced radiation exposure.

KEY WORDS: GNRFA, monopolar, Trident™, WOMAC, knee OA, radioactivity, fluoroscopy