Cooled Radiofrequency Ablation Versus Cryo-neurolysis of Genicular Nerves: A Comparative Study on Pain Relief and Functional Outcomes in Symptomatic Knee Osteoarthritis.

PURPOSE

This study aimed to compare the effectiveness of cooled radiofrequency ablation (cRFA) and cryo-neurolysis (CN) of genicular nerves in alleviating pain and improving function in patients with advanced knee osteoarthritis (KOA).

METHODS

In this single-centre, prospective, randomised study, thirty patients with moderate to severe KOA (Kellgren-Lawrence grade 3-4) who responded to a fluoroscopy-guided genicular nerve block were assigned (1:1) to cRFA (n = 15) or CN (n = 15). Pain and function were assessed at baseline and 1-, 3-, 6-, and 12-month post-procedure using the Visual Analog Scale (VAS) and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Linear mixed-effects models (LMM) analysed longitudinal outcomes, incorporating fixed effects for group, time, and interaction with random patient intercepts.

RESULTS

Thirty patients were included in this study. Both groups significantly reduced VAS and WOMAC scores over time (p < 0.001). LMM-predicted VAS scores decreased from 7.1 ± 0.4 (CN) and 7.2 ± 0.4 (cRFA) at baseline to 2.0 ± 0.3 and 2.5 ± 0.3 at 12 months, respectively (p = 0.20), with a transient CN advantage at 6 months (1.5 ± 0.3 vs. 2.4 ± 0.3, p = 0.03). WOMAC scores fell from 70.0 ± 3.2 (CN) and 73.0 ± 3.2 (cRFA) to 28.0 ± 2.9 and 31.0 ± 2.9 (p = 0.41), showing no significant group differences (interaction p = 0.36). Adverse events were minimal, consisting of transient numbness in 2 CN patients.

CONCLUSION

Based on the current study's results, cRFA and CN offer comparable, sustained pain relief and functional improvement in advanced KOA, with CN providing a mid-term VAS benefit. Both are viable options for managing refractory KOA pain.