Effectiveness of Low Level Laser Therapy and Low Intensity Pulsed Ultrasound on Neuropathic Pain among the Experimentally Induced Peripheral Nerve Injury in Rat Model

Abstract

Background: Peripheral nerve injury creates an impact on the inflammatory process, leading to an elevation in
Hypoxia-inducible factor-1 alpha levels, which contributes to the development and progression of neuropathic
pain. An innovative approach to alleviating neuropathic pain involves targeting inflammation.
Purpose: This study aims to compare the effect of Low-Level Laser Therapy (LLLT) and Low-Intensity Pulsed
Ultrasound (LIPUS) on neuropathic pain among the experimentally induced peripheral nerve injury in rat model.
Methods: Rats with induced sciatic nerve crush injury were randomly divided into three groups: control, LIPUS
treatment, and LLLT treatment. Mechanical paw withdrawal threshold analysis was performed before the injury
and from POD 2nd, 7th, 14th, and 21st to assess effectiveness of the treatment.
Result: Low-Level Laser Therapy (LLLT) group showing statistically greater improvement on POD 14 and 21
compared to both the LIPUS group and the control group in terms of paw withdrawal threshold measurements
among rats with crush-induced neuropathic pain (P < 0.001).
Conclusion: This study found that the use of LLLT has a beneficial effect in the management of neuropathic pain
and control of analgesia compared to LIPUS by inhibiting the upregulation of HIF-1α synthesis during ischemia,
hypoxia, and inflammation. However further studies are recommended to analyze long term results in larger
sample to control neuropathic pain.