Laser therapy: a randomized, controlled trial of the effects of low-intensity Nd:YAG laser irradiation on musculoskeletal back pain. In chronic low back pain, low level laser therapy combined with exercise is more beneficial than exercise alone in the long term: a randomised trial. Efficacy of low power laser therapy and exercise on pain and functions in chronic low back pain. Low-energy laser treatment and exercise for chronic low back pain: double-blind controlled trial.
To assess the effectiveness of low-intensity laser therapy in the treatment of musculoskeletal low back pain.
                A double-masked, placebo-controlled, randomized clinical trial.
                A physical medicine and rehabilitation clinic.
                Sixty-three ambulatory men and women between the ages of 18 and 70yrs with symptomatic nonradiating low back pain of more than 30 days' duration and normal neurologic examination results.
                Subjects were bloc randomized into two groups with a computer-generated schedule. All underwent irradiation for 90 seconds at eight symmetric points along the lumbosacral spine three times a week for 4 weeks by a masked therapist. The sole difference between the groups was that the probes of a 1.06 microm neodymium:yttrium-aluminum-garnet laser emitted 542mW/cm2 for the treated subjects and were inactive for the control subjects.
                Subject's perception of benefit, level of function as assessed by the Oswestry Disability Questionnaire, and lumbar mobility.
                The treated group had a time-dependent improvement in two of the three outcome measures: perception of benefit and level of function. These results were most marked at the midpoint evaluation (p < .005, p < .01) and end of treatment (p < .017, p < .001) but tended to lessen at the 1-month follow-up (p < .10, p < .004). Lumbar mobility did not differ between the groups at any time. All tests were two-sample t tests with unequal variances.
                Treatment with low-intensity 1.06 microm laser irradiation produced a moderate reduction in pain and improvement in function in patients with musculoskeletal low back pain. Benefits, however, were limited and decreased with time. Further research is warranted. Is low level laser therapy an effective adjuvant intervention for chronic low back pain?
                Randomised trial with concealed allocation, blinded assessors and intention-to-treat analysis.
                Sixty-one patients who had low back pain for at least 12 weeks.
                One group received laser therapy alone, one received laser therapy and exercise, and the third group received placebo laser therapy and exercise. Laser therapy was performed twice a week for 6 weeks.
                Outcomes were pain severity measured using a 10-cm visual analogue scale, lumbar range of motion measured by the Schober Test and maximum active flexion, extension and lateral flexion, and disability measured with the Oswestry Disability Index on admission to the study, after 6 weeks of intervention, and after another 6 weeks of no intervention.
                There was no greater effect of laser therapy compared with exercise for any outcome, at either 6 or 12 weeks. There was also no greater effect of laser therapy plus exercise compared with exercise for any outcome at 6 weeks. However, in the laser therapy plus exercise group pain had reduced by 1.8 cm (95% CI 0.1 to 3.3, p = 0.03), lumbar range of movement increased by 0.9 cm (95% CI 0.2 to 1.8, p < 0.01) on the Schober Test and by 15 deg (95% CI 5 to 25, p < 0.01) of active flexion, and disability reduced by 9.4 points (95% CI 2.7 to 16.0, p = 0.03) more than in the exercise group at 12 weeks.
                In chronic low back pain low level laser therapy combined with exercise is more beneficial than exercise alone in the long term. The aim of this study was to determine whether low power laser therapy (Gallium-Arsenide) is useful or not for the therapy of chronic low back pain (LBP).
                This study included 75 patients (laser + exercise-25, laser alone-25, and exercise alone-25) with LBP. Visual analogue scale (VAS), Schober test, flexion and lateral flexion measures, Roland Disability Questionnaire (RDQ) and Modified Oswestry Disability Questionnaire (MODQ) were used in the clinical and functional evaluations pre and post therapeutically. A physician, who was not aware of the therapy undertaken, evaluated the patients.
                Significant improvements were noted in all groups with respect to all outcome parameters, except lateral flexion (P < 0.05).
                Low power laser therapy seemed to be an effective method in reducing pain and functional disability in the therapy of chronic LBP.
                Copyright 2003 Wiley-Liss, Inc. Twenty patients with chronic low back pain were enrolled in a randomized double-blind trial to test the efficacy of low-energy laser biostimulation combined with exercise. Ten patients received low-energy gallium-arsenide laser treatment, and ten received placebo laser treatment. Both groups were also placed on an active exercise program. Visual analogue and disability pain scores were assessed pretreatment and one month posttreatment and showed significant (p less than .02) improvements in both groups, but no relative advantage was found for either group. Objective parameters using computerized triaxial measurements of range of motion, isometric torque, and isodynamic velocity were also performed before and after treatment. There were significant improvements in objective parameters in both the laser and placebo groups, but no relative advantage accrued to either group. Under the conditions of this study, low-energy laser stimulation plus exercise did not provide a significant advantage over exercise alone.
Based on the heterogeneity of the populations, interventions and comparison groups, we conclude that there are insufficient data to draw firm conclusions on the clinical effect of LLLT for low-back pain. 
There is a need for further methodologically rigorous RCTs to evaluate the effects of LLLT compared to other treatments, different lengths of treatment, wavelengths and dosages.