1892: Genicular Nerve Block for Pain Management in Patients with Knee Osteoarthritis: A Randomised Double-blind Placebo Controlled Trial

Ernst Shanahan¹, Fin Cai², Frank Voyvodic², Suellen Lyne², Richard Woodman¹, Kokum Dissanayake², Kate Paddick², Giovanna Cheung² and Lucinda Robinson², ¹Flinders University, Adelaide, Australia, ²SALHN, Adelaide, Australia

Background/Purpose: To determine whether Genicular Nerve Block (GNB) is an efficacious treatment for patients with knee osteoarthritis (OA)

Methods: Adults with symptomatic knee OA for greater than 3 months were invited to participate. Patients were randomised into two groups. Under ultrasound guidance subjects in the treatment arm received 5.7 mg (1 ml) of celestone and 3 mls of 0.5% of bupivacaine infiltrated around three genicular nerves, with subjects in the placebo receiving three 1 ml normal saline injections. Participants were followed up for 3 months with primary outcome measures being pain, stiffness and disability measured on the Western Ontario and McMaster Universities Arthritis index (WOMAC) score, and pain measured by a 100-point Visual Analogue Scale (VAS) measured at baseline,2, 4, 8 and 12 weeks. Secondary outcome measures included patient satisfaction measured using the Global Perceived Effect (GPES) score and the Intermittent and Constant Osteoarthritis Pain Score (knee version).

Results: All mean scores showed clinical and statistical improvement in the treatment arm at all time points compared to baseline. Of the primary outcome measures, the WOMAC score improved from a baseline of 55 (CI 49-61) to 33 (CI 27-39) at week 2, 34 (CI 28-40) at week 4, 39 (CI 33-45) at week 8 and 43 (CI 36-49) at week 12. The placebo group showed a small (non-significant) placebo effect at each time interval. VAS scores showed similar improvements as did the secondary outcome measures. All scores differed between the two groups at each time point, with improvement across all weeks in the treatment arm compared with baseline and the placebo group. There were no reported adverse outcomes.

Conclusion: These results demonstrate that GNB is an efficacious treatment for knee pain from OA and is a useful alternative for the management of this condition.
Total WOMAC scores

VAS scores
Disclosures: E. Shanahan, None; F. Cai, None; F. Voyvodic, None; S. Lyne, None; R. Woodman, None; K. Dissanayake, None; K. Paddick, None; G. Cheung, None; L. Robinson, None.