Neglect of relevant treatment recommendations in the conduct and reporting of a laser therapy knee osteoarthritis trial: letter to the editor.

We read with interest the article by Gomes et al. entitled: "Exercise program combined with electrophysical modalities in subjects with knee osteoarthritis: A randomised, placebo-controlled clinical trial". Gomes et al. concluded that the low-level laser therapy (LLLT) did not reduce knee osteoarthritis pain when applied as an adjunct to exercise therapy. We argue that Gomes et al. neglected relevant laser treatment recommendations in the conduct and reporting of the trial.Gomes et al. did not state the Joules per treatment spot applied. We calculated the Joules applied from other laser information in the report and found that it is too low of a dose according to the World Association for Laser Therapy (WALT) guidelines. Furthermore, we have published a meta-analysis of 22 placebo-controlled trials demonstrating a significant difference in pain-relieving effect between doses in adherence and non-adherence to the WALT guidelines. However, neither the WALT guidelines, nor our meta-analysis was mentioned by Gomes et al.Moreover, Gomes et al. did not state whether the output power of the laser device was measured, and this is concerning because in the city of São Paulo, where the trial was conducted, most laser devices have been found to deliver less of a dose than specified by the manufacturers.In summary, we found that the best available evidence regarding effective and ineffective LLLT dosing from systematic reviews was neglected in the conduct and reporting of the trial, and that the laser device may not have been calibrated.

Effects of photobiomodulation therapy on inflammatory mediators in patients with chronic non-specific low back pain: Protocol for a randomized placebo-controlled trial.

INTRODUCTION: Low back pain (LBP) is ranked as one of the most prevalent health conditions. It is likely that some inflammatory mediators could be associated with pain and disability in these patients. Photobiomodulation therapy (PBMT) is a non-pharmacological therapy often used in patients with LBP and one of the possible mechanisms of action of therapy is modulate inflammatory mediators. However, to date there are no studies that evaluated the effects of PBMT on the levels of inflammatory mediators in patients with LBP. The aim of this study is to evaluate the acute effects of PBMT on systemic levels of inflammatory mediators and pain intensity in patients with chronic non-specific low back pain. METHODS AND ANALYSIS: This is a prospectively registered, two-arm randomized placebo-controlled trial with blinded patients, assessors and therapists. Eighteen patients with chronic non-specific LBP will be randomized into 2 groups: placebo or active PBMT. The treatment will be provided in a single session. The primary outcome will be levels of prostaglandin E2 (PGE2). The secondary outcomes will be levels of necrosis factor alpha (TNF-α), interleukin 6 (IL-6) and pain intensity. Biochemical and clinical outcomes will be measured at baseline and 15 minutes after the single treatment session. DISCUSSION: Despite PBMT be used in musculoskeletal disorders such as LBP, to the best of our knowledge this is the first study that will investigate a possible biological mechanism behind the positive clinical effects of PBMT on non-specific chronic low back pain. ETHICS AND DISSEMINATION: The study was approved by the Regional Research Ethics Committee. The results will be disseminated through publication in peer-reviewed international journal and conferences. TRIAL REGISTRATION NUMBER: NCT03859505.