Effectiveness of Low-Level Laser Therapy on Pain and Function in Individuals with Musculoskeletal-Related Disorders, A Pilot Study

Purpose: o se: The primary purpose of this study is to investigate the effectiveness of Low-Level Laser Therapy (LLLT) on pain and function in individuals presenting with pain associated with musculoskeletal dysfunction. A secondary purpose is to examine the effects of age on observed outcomes associated with using LLLT. Methods: The study protocol included 12 sessions of LLLT using a class 3-B laser device. Treatment dosage for the LLLT was determined according to recommendations published by the World Association for Photobiomodulation Therapy (WALT). Physical therapists determined treatment locations for LLLT application during a pre-intervention evaluation. Following completion of the intervention protocol, participants were re-evaluated by physical therapists to collect post-intervention data. Pre- and post- intervention outcomes were compared via paired t-test or nonparametric equivalent. For the relationship between age and outcomes, Spearman's Rho correlations were used. Results: 31 individuals were included in the study with participant ages ranging from 29 to 77 years old, and average age of 55 years. Participant Current, Best, and Worst pain significantly improved with mean difference of 2, 2, 1 points respectively on Numeric Rating Scale (NRS) (p-values ranging from <0.001 to 0.00164). Patient-Specific Functional Scale (PSFS) measurements also demonstrated significant improvement (p-values ranging from <0.001 to 00248). Average grip strength significantly improved by 6.6 pounds (p= 0.047), while average joint range of motion increased significantly by 6.7 degrees (p= 0.024). No significant differences noted with lower extremity strength measured using manual muscle test (p= 0.204). No significant differences noted with trunk flexion range of motion measured using finger-tip to floor reach method (p= 0.942). A significant correlation was found between age and change in Worst pain (p= 0.024). Correlation between age and change in function on the PSFS was not significant (p= 0.147). Conclusions: o nclus io ns: LLLT was associated with significant improvements in pain ratings and measurements of function in individuals presenting with pain related to musculoskeletal dysfunction. A positive correlation was demonstrated between age and changes in worst-reported pain while no significant correlation could be found between age and change in function following treatment with LLLT.