Level of pain, muscle strength and posture: effects of PBM on an exercise program in women with knee osteoarthritis - a randomized controlled trial

Lasers Med Sci. 2020 Dec;35(9):1967-1974. doi: 10.1007/s10103-020-02989-1. Epub 2020 Mar 10.


To evaluate the effectiveness of an exercise program associated to photobiomodulation (PBM) on pain, postural changes, functionally, and muscular strength in women, one of the risk factors, with knee osteoarthritis (OA). A randomized controlled trial, with a blinded assessor and intention-to-treat analysis and placebo control. Sixty-two participants with knee OA (with confirmed radiological diagnosis) were evaluated for this study. However, 34 were considered eligible and were randomized into two groups: EPPG - exercise and PBM placebo group (n = 17) and EPAG - exercise and PBM active group (n = 16), but one participant was excluded of EPAG. The exercise program and PBM (808 nm, 100 mW/point, 4 J/point, 56 J total, 91 J/cm2) were realized twice a week, during 8 weeks. West Ontario and the McMaster University Osteoarthritis Index (WOMAC) and Lequesne questionnaires, 1-repetition maximum test (1-RM) and posture evaluation software (SAPO) were used to analyze the effects of the therapies. In intragroup analysis, a significant improvement in pain WOMAC (p < 0.001), stiffness (p < 0.001), function (p < 0.001), Lequesne (p < 0.001), and 1-RM (all muscle groups) (p < 0.001) were observed. In this study, the exercise program improved pain, function, and muscle strength of all the participants. However, PBM, in the parameters used, did not optimize the effects of the exercise program in women with knee OA.

Keywords: Exercise; Muscle strength; Osteoarthritis; Pain; Photobiomodulation; Posture.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Exercise Therapy*
  • Female
  • Humans
  • Low-Level Light Therapy*
  • Male
  • Middle Aged
  • Muscle Strength / physiology*
  • Osteoarthritis, Knee / complications
  • Osteoarthritis, Knee / physiopathology*
  • Osteoarthritis, Knee / radiotherapy*
  • Pain / etiology*
  • Pain Measurement
  • Posture / physiology*
  • Surveys and Questionnaires