Comparison of the effects of low-level laser and pulsed and continuous ultrasound on pain and physical disability in chronic non-specific low back pain: a randomized controlled clinical trial.

Objective: To compare the short-term effects of pulsed laser and pulsed and continuous ultrasound on pain and functional disability in women with chronic non-specific low back pain.

Methods: The sample was composed of 100 volunteers randomly allocated into four groups: The Pulsed Laser Group (n = 26) was treated with 3 J/cm; the Pulsed Ultrasound Group (n = 24; 3 MHz) was treated with 1 W/cm; the Continuous Ultrasound Group (n = 26; 1 MHz) was treated with 1 W/cm; and a Control Group (n = 24), where the patients were still waiting for treatment. Before and after 10 sessions of treatment, the intensity of pain was assessed using the visual analogue scale (VAS), the quality of pain was evaluated using the McGill pain questionnaire and functional disability was investigated using the Roland-Morris questionnaire.