Primary Studies
-
Effectiveness of Photobiomodulation in Reducing Pain and Disability in Patients with Knee Osteoarthritis: A Systematic Review with Meta-Analysis
By Oliveira et al. Phys Ther. 2024.
• 2024
• Journal: Phys Ther
Abstract: This systematic review examined PBM versus placebo in knee osteoarthritis and concluded that PBM reduces pain intensity and may improve disability, but evidence certainty remains very low and more rigorous trials are needed.
One Sentence Outcome:
Study Parameters: 10 studies, 542 participants; PBM vs placebo for knee OA pain and disability outcomes.
Device Parameters: Varied across included PBM studies.
Evidence Level: Level 1a (systematic review/meta-analysis)
Study Type: Systematic review with meta-analysis
Outcome Direction: Mixed-positive
-
Effects of low-level and high-intensity laser therapy as adjunctive to rehabilitation exercise on pain, stiffness and function in knee osteoarthritis: a systematic review and meta-analysis
By Ahmad et al. Physiotherapy. 2022.
• 2022
• Journal: Physiotherapy
Abstract: This review compared low-level and high-intensity laser therapy as adjuncts to rehabilitation exercise in knee osteoarthritis. Both approaches improved pain, stiffness, and function, with stronger indirect evidence for HILT plus exercise.
One Sentence Outcome:
Study Parameters: 10 trials: six LLLT+exercise studies, three HILT+exercise studies, one study of both modalities.
Device Parameters: Varied; review compared LLLT+exercise and HILT+exercise across included trials.
Evidence Level: Level 1a (systematic review/meta-analysis)
Study Type: Systematic review and meta-analysis
Outcome Direction: Positive
-
A systematic review and network meta-analysis on the optimal wavelength of low-level light therapy (LLLT) in treating knee osteoarthritis symptoms
By Fan et al. Osteoarthritis and Cartilage. 2024.
• 2024
• Journal: Osteoarthritis and Cartilage
Abstract: This network meta-analysis compared different low-level light therapy wavelengths for knee OA. Overall LLLT was superior to sham for pain, with 904–905 nm showing the highest ranking for pain reduction, though the certainty of evidence was low.
One Sentence Outcome:
Study Parameters: 13 studies, 673 participants with knee OA; compared wavelength-specific effects versus sham and between wavelength groups.
Device Parameters: Compared wavelength groups; 904–905 nm ranked highest for pain reduction, followed by multi-wavelength and 785–850 nm.
Evidence Level: Level 1a (systematic review/meta-analysis)
Study Type: Systematic review and network meta-analysis
Outcome Direction: Mixed-positive
-
Short-term efficacy of low-level laser therapy in patients with knee osteoarthritis: a randomized placebo-controlled, double-blind clinical trial.
By Fukuda et al. Rev Bras Ortop. 2015.
• 2015
• Journal: Rev Bras Ortop
Abstract: This randomized double-blind placebo-controlled trial enrolled 47 patients with knee OA and applied a 904 nm AsGa laser three times weekly for nine sessions. The laser group showed significant short-term improvements in pain and function.
One Sentence Outcome:
Study Parameters: 47 patients (79 knees); laser vs placebo; 9 points irradiated on the knee; pain, Lequesne index, TUG, ROM, and strength assessed.
Device Parameters: Wavelength: 904 nm; Mean power: 60 mW; Beam area: 0.5 cm²; Energy: 3 J/point; Time: 50 sec/point; Sessions: 9 over 3 weeks
Evidence Level: Level 1b (RCT)
Study Type: Randomized placebo-controlled double-blind clinical trial
Outcome Direction: Positive
Supplemental Studies
-
Low-intensity laser therapy efficacy evaluation in mice subjected to acute arthritis condition.
By
• 2017
• Journal: J Photochem Photobiol B
Abstract: “LILT showed signs of an anti-inflammatory effect when applied once, but promoted increased resorptive area when used for two sessions, indicating the importance of a controlled LILT protocol to reach therapeutic effects.”
One Sentence Outcome:
Study Parameters: Sessions: 1 or 2
Device Parameters: λ 660 808 905 nm
Evidence Level: Preclinical animal study
Study Type: Mouse
Outcome Direction: Positive / supportive PBM outcome
-
Interleukin-10 and collagen type II immunoexpression are modulated by photobiomodulation associated to aerobic and aquatic exercises in an experimental model of osteoarthritis.
By
• 2018
• Journal: Lasers Med Sci
Abstract: “These results suggest that PBM associated with aerobic and aquatic exercise training were effective in mediating chondroprotective effects and maintaining the integrity of the articular tissue in the knees of OA rats.”
One Sentence Outcome:
Study Parameters: Sessions: nan
Device Parameters: λ 808 nm
Evidence Level: Preclinical animal study
Study Type: Rat
Outcome Direction: Positive / supportive PBM outcome
-
Low-intensity laser therapy efficacy evaluation in FVB mice subjected to acute and chronic arthritis.
By
• 2017 epub
• Journal: Lasers Med Sci
Abstract: “Kruskal-Wallis testing indicated no significant differences between knees affected by acute arthritis and treated once with LILT and an injured knee without treatment (p > 0.05) for 660 and 808 nm with some improvements for the 905-nm LILT. Mice receiving two treatments for acute arthritis showed exacerbation of inflammation and articular resorption following therapy with a 660-nm continuous laser (p < 0.05). For chronic inflammation, differences were not noted between LILT treated and untreated injured knee joints (p > 0.05). Among the lasers, the 905 nm tends to show better results for anti-inflammatory effect in acute arthritis, and the 660 nm showed better results in chronic arthritis. In conclusion, LILT wavelength selection depends on the arthritis condition and can demonstrate anti-inflammatory effects for chronic arthritis and reduced resorption area in this murine model.”
One Sentence Outcome:
Study Parameters: Sessions: nan
Device Parameters: λ 660 808 905 nm
Evidence Level: Preclinical animal study
Study Type: Mouse
Outcome Direction: Positive / supportive PBM outcome
-
The fluence effects of low-level laser therapy on inflammation, fibroblast-like synoviocytes, and synovial apoptosis in rats with adjuvant-induced arthritis.
By
• 2014
• Journal: Photomed Laser Surg
Abstract: “LLLT at a fluence of 4.5 J/cm2 significantly reduced infiltration of inflammatory cells and expressions of TNF-α-, MMP3- and 5B5-like immunoreactivities, as well as resulting in more TUNEL-positive apoptotic cells in the synovium. No significant changes were observed in these biochemicals and inflammation in arthritic animals treated with 72 J/cm2.” “LLLT with low fluence is highly effective in reducing inflammation to sites of injury by decreasing the numbers of FLS, inflammatory cells, and mediators in the CFA-induced arthritic model. These data will be of value in designing clinical trials of LLLT for RA.”
One Sentence Outcome:
Study Parameters: Sessions: 10 10
Device Parameters: λ 780 nm
Evidence Level: Preclinical animal study
Study Type: Rat
Outcome Direction: Positive / supportive PBM outcome
