The Efficiency of Pulsed Radiofrequency Application on L5 and L6 Dorsal Roots in Rabbits Developing Neuropathic Pain

Abstract

Injury of a peripheral nerve may lead to neuropathic pain, a form of chronic pain that does not respond to traditional pain therapies. The aim of this study was to investigate the effect of pulsed radiofrequency (PRF) applied to the L5 and L6 dorsal roots on the neuropathic pain that develops after sciatic nerve injury in rabbits. In this study, 18 New Zealand rabbits were used. These were divided into 3 groups. In groups 1 and 2, the left sciatic nerve was tightly ligated as a partial ligation model with 4-0 silk sutures. Group 3 was a sham group. Pulsed radiofrequency was applied to group 1 rabbits on both dorsal roots at 42 degrees C for 8 mins. The responses of all the groups to thermal and mechanical stimuli were measured for a period of 4 weeks after this process. Ten days after ligation of the left sciatic nerve and before PRF application, neuropathic pain occurred; the responses of groups 1 and 2 to the hot plate test and to the mechanical stimulus were lower (P < 0.005) when compared with the baseline values. There were no statistically significant differences between baseline values and group 1 rabbits' responses to the hot plate test 2 weeks after the application of PRF or to the mechanical stimulus 3 weeks after RF application. The decrease seen in group 2 persisted after 4 weeks (P < 0.001). The hyperalgesia that develops as a result of neuropathic pain in rabbits was observed to be reduced by PRF application.