Photobiomodulation therapy has a negligible effect as an adjunct to motor control exercise in people with chronic non-specific low back pain: a randomised trial.

QUESTION: In adults with chronic non-specific low back pain, does adding photobiomodulation therapy (PBMT) to a program of motor control exercise (MCE) improve pain intensity, disability and circulating prostaglandin E2 (PGE2) concentrations compared with sham PBMT plus MCE?

DESIGN

A randomised controlled trial was conducted with concealed allocation, intention-to-treat analysis and blinding of participants, therapists and assessors.

PARTICIPANTS

Adults aged 18 to 65 years seeking treatment for chronic non-specific low back pain of ≥ 3 months in duration.

INTERVENTION: Participants were randomly allocated to active PBMT plus MCE or sham PBMT plus MCE. Both groups received 12 treatment sessions over 6 weeks.

OUTCOME MEASURES: Assessments were completed at baseline and 6 weeks, with follow-up assessments at 1 month after the end of the intervention period and at 3, 6 and 12 months after randomisation. Primary outcomes were pain intensity (0 to 10 numerical rating scale) and disability (0 to 24 Roland-Morris Disability Questionnaire) at 6 weeks, in which higher scores indicated greater severity. Secondary outcomes were: pain and disability at follow-up timepoints; circulating PGE2 concentrations at 6 weeks; and medication use, concomitant care and adverse events throughout the follow-up period.

RESULTS

A total of 148 participants were randomised (74 per group). The intention-to-treat analysis showed that PBMT plus MCE had a negligible effect compared with sham plus MCE at 6 weeks for pain intensity (MD -0.4 points, 95% CI -1.2 to 0.4), disability (MD -0.7 points, 95% CI -2.4 to 0.9) or circulating PGE2 concentrations (MD 31 pg/ml, 95% CI -4 to 66). Negligible between-group differences were observed throughout the 12-month follow-up period, and no treatment-related adverse events occurred.

CONCLUSION

Adding PBMT to MCE did not provide clinically important additional improvements in pain intensity, disability or circulating PGE2 concentrations compared with sham plus the same exercise program.

REGISTRATION: NCT05487118.