Effects of Laser Therapy and Exercise in Participants With Chronic Low Back Pain

The objective of this clinical trial is to evaluate the additional effects of Photobiomodulation Therapy in participants with chronic non-specifc low back pain in the short and long term.

• exercise + photobiomodulation therapy (Device): Treatment sessions will be provided twice a week for 6 weeks (totaling 12 sessions) with participants receiving either placebo or active PBMT + exercise protocol.

Primary outcomes

• Change Of Pain intensity at post-intervention [Baseline; Immediately after the last intervention]: Measured by the Visual Analogue Scale (VAS). The VAS evaluates pain intensity levels perceived by the patient on an 11-point scale ranging from 0 to 10, with 0 being 'no pain' and 10 'the worst possible pain'.
• Change Of Pain intensity at 3 months post-intervention [Baseline; 3 months after the last intervention]: Measured by the Visual Analogue Scale (VAS). The VAS evaluates pain intensity levels perceived by the patient on an 11-point scale ranging from 0 to 10, with 0 being 'no pain' and 10 'the worst possible pain'.
• Change of Disability associated with low back pain at post-intervention [Baseline; Immediately after the last intervention]: Measured by the Roland-Morris Disability Questionnaire. The questionnaire consists of 24 items that describe situations that patients may have difficulty performing on a daily basis due to LBP. The greater the number of affirmative answers is, the higher the level of functional disability associated with LBP.
• Change of Disability associated with low back pain at 3 months post-intervention [Baseline; 3 months after the last intervention]: Measured by the Roland-Morris Disability Questionnaire. The questionnaire consists of 24 items that describe situations that patients may have difficulty performing on a daily basis due to LBP. The greater the number of affirmative answers is, the higher the level of functional disability associated with LBP.

Secondary outcomes

• Change Of Pain intensity at 12 months post-intervention [Baseline; 12 months after the last intervention]: Measured by the Visual Analogue Scale (VAS). The VAS evaluates pain intensity levels perceived by the patient on an 11-point scale ranging from 0 to 10, with 0 being 'no pain' and 10 'the worst possible pain'.
• Change of Disability associated with low back pain at 12 months post-intervention [Baseline; 12 months after the last intervention]: Measured by the Roland-Morris Disability Questionnaire. The questionnaire consists of 24 items that describe situations that patients may have difficulty performing on a daily basis due to LBP. The greater the number of affirmative answers is, the higher the level of functional disability associated with LBP.
• Changes os Mental health [Baseline; Immediately after the last intervention; 3 and 12 months after the last intervention]: Measured by the reduced version of the Anxiety, Depression and Stress Scale-21. It is a self-report instrument composed of three subscales with seven items each, to assess depression, anxiety and stress in the previous week. The variations in scores correspond to symptom levels, which vary between "normal" and "very severe".
• Changes of Disability associated with low back pain [Baseline; Immediately after the last intervention; 3 and 12 months after the last intervention]: Measured by the Oswestry Low Back Pain Disability Questionnaire. The scale consists of 10 questions with six alternatives, the value of which ranges from 0 to 5. It is classified into: minimum disability (0 - 20%), moderate disability (21- 40%), severe disability (41 - 60%) , a patient who is disabled (61 - 80%), and an individual restricted to bed (81 - 100%).
• Changes of Mobility of the lumbar and sacral segments [Baseline; Immediately after the last intervention; 3 and 12 months after the last intervention]: Measured by the modified Schober test
• Changes of Strength of the trunk extensor muscle [Baseline; Immediately after the last intervention; 3 and 12 months after the last intervention]: Measured by the Sorensen Test

Sex: All, ages: 18 Years to 65 Years

Inclusion Criteria:

* Patients with non-specific chronic LBP, defined as pain or discomfort between the costal margins and inferior gluteal folds with or without referred pain to the lower limbs;
* Persistent LBP for at least 3 months;
* Low back pain of intensity reported 3 or higher by the Visual Analogue Scale (VAS), at least once in the previous 7 days;
* Aged between 18 and 65 years;
* Both genders.

Exclusion Criteria:

* Patients with severe skin diseases (eg, skin cancer, erysipelas, severe eczema, severe dermatitis, severe psoriasis and severe hives lupus);
* Participants with known or suspected serious spinal pathology (e.g., fractures, tumors, inflammatory, rheumatologic disorders, or infective diseases of the spine);
* Nerve root compromise;
* History of previous spinal surgery (even in a segment other than the lumbar spine) or scheduled surgery;
* Pain due to or associated with pregnancy or structural deformity (for example, scoliosis);
* Pregnancy;
* Comorbid health conditions that could prevent active participation in the exercise programs such as high blood pressure, pregnancy, or cardio-respiratory illnesses;
* Having answered "yes" to any of the questions in the Physical Activity Readiness Questionnaire (PAR-Q);
* Be treated with PBMT;
* Being under physiotherapeutic treatment or perform physical exercise;
* Who are using NSAID or start it during the trial;
* Who have inability to tolerate the proposed experimental procedures (such as tests of mobility and strength of the lumbar muscles).

• Flávia Santos, Principal investigator, Federal University of the Valleys of Jequitinhonha and Mucuri