Low-dose laser acupuncture for non-specific chronic low back pain: a double-blind randomised controlled trial

Objective To determine if infrared laser acupuncture (LA) may have a specific effect in reducing pain and disability in treatment of chronic low back pain (LBP). Methods This was a double-blind sham laser controlled trial performed in general practices in Perth, Western Australia. The participants were 144 adults with chronic non-specific LBP. They were randomised to receive eight once-weekly treatments. Laser machines (20 mW, 840 nm diode, power density 0.1 W/cm(2)) stimulated points in three treatment groups: sham (0 joules/point), low dose (0.2 J/point) and high dose (0.8 joules/point). Participants were followed-up at 1 and 6 weeks, and 6 and 12 months post treatment. Primary outcomes were pain (Numerical Pain Rating Scale (NPRS)) and disability (Oswestry Disability Inventory (ODI)) at 6 weeks post treatment. Secondary outcomes included numerical rating scale for limitation of activity, global assessment of improvement, analgesic usage and adverse effects after treatment. Results The analysis showed no difference between sham and the laser groups at 6 weeks for pain or disability. There was a significant reduction in mean pain and disability in all groups at 6 weeks (p<0.005); NPRS: sham (-1.5 (95% CI -2.1 to -0.8)), low dose (-1.3 (-2.0 to -0.8)), high dose (-1.1 (-1.7 to -0.5)). ODI: sham (-4.0 (-7.1 to -1.0)), low dose (-4.1, (-6.7 to -1.5)), high dose (-2.6 (-5.7 to 0.5)). All secondary outcomes also showed clinical improvement over time but with no differences between groups. Conclusions LA using energy density range (0-4 J/cm(2)) for the treatment of chronic nonspecific LBP resulted in clinical improvement unrelated to laser stimulation.