Effect of radiofrequency ablation of genicular nerves on the isokinetic muscle strength of knee joint in patients with osteoarthritis knee: A randomized double-blind sham controlled clinical trial.

Abstract

Background: This randomised controlled trial evaluated the effect of radiofrequency ablation (RFA) of genicular nerve on muscle strength in osteoarthritis knee patients with chronic pain.

Methodology: Fifty-four patients with chronic knee osteoarthritis, experiencing significant pain (VNRS > 50) and moderate to severe disease (KL grade ≥ 2) were enrolled. Group 1 received RFA of genicular nerves of the affected knee while Group 2 received a sham procedure. The primary outcome was change in knee muscle strength evaluated using isokinetic peak torque(IPT) using IsoforceTM isokinetic dynamometer at 3 months. Secondary outcomes included changes in pain scores, function, perceived effect of the treatment and compliance to physiotherapy.

Results: At 3 months, significant difference was observed between IPT of flexor muscle at 60 and 180 degrees between the treatment and the Sham control (p-value = 0.01). No significant difference was observed in the extensor muscle strength. Within-group analysis revealed a significant increase in the IPT values for both extension and flexion at 60 and 180 degrees/sec evident across various time intervals. Group1 consistently reported lower VNRS scores at all time points. WOMAC scores of both groups were significantly different at all timepoints, with higher scores indicating reduced functionality in Group2. The GPE and compliance to physiotherapy were higher in Group1 patients at all times of follow up albeit decreasing trend in later periods.

Conclusion: Application of RFA to genicular nerves in chronic OA knee patients resulted in better pain relief, improved functionality and increased muscle strength at extension and flexion at 3 months follow-up.