Effect of Class Iv Laser on Pain and Lumbar Canal Diameter Among Patients with Lumbar Disc Herniation: A Placebo Controlled Trial

Background: Lumbar disc herniation (LDH) is a common condition affecting working-age individuals, presenting with back pain. Class IV therapeutic laser therapy may help reduce inflammation, promote intervertebral disc healing and may increase the anterior-posterior (AP) diameter of the lumbar canal, providing pain relief. Purpose: This study aimed to evaluate the effect of Class IV therapeutic laser in pain and lumbar canal diameter among patients with LDH. Participants: 66 participants (59 males and 7 females) aged 30 to 60 years, all experiencing low back pain associated with LDH were included in the study. Methods: This double-blinded, sham-controlled trial randomly assigned 66 participants into two groups (33 each). The experimental group received Class IV therapeutic laser (9W, 3780J), while the control group received a sham treatment. Both groups followed a regimen of hot pack, exercises, and lumbar corset. Pain with numerical pain rating scale (NPRS) and AP diameter of the lumbar canal with magnetic resonance imaging (MRI) were assessed at baseline and 10 weeks. Results: Wilcoxon signed – rank test and Mann-Whitney U test were used for analysis. There was a significant decrease in NPRS score (p=0.0001) (mean 2.97 ± 1.36), and increase in lumbar canal AP diameter (mean 12.93 ± 3) in experimental group as compared to control group (mean 12.09 ± 1.63) Conclusion: Class IV laser has been found effective in pain reduction and may improve canal diameter in LDH patients. Implications: This study may aid in developing a treatment protocol for clinicians managing low back pain in LDH.