TABLE 1.
Summary of the light parameters used in RCTs applying PBMT to treat KOA patients.
| Study | Sample size | Light source | Wavelength (nm) | Output power (mW) | Spot area (cm2) | Power density (mW/cm2) | Energy density (J/cm2) | Total energy per point (J) | Number of points | Duration-frequency-sessions | Major results |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Stelian et al. (1992) | 50 | Laser | 633 | 18/75 | — | 8/34 | 5.1 | — | — | 15 min-2/d-20 | Pain reduction in both laser groups by more than 50%. Significant functional improvement |
| Laser | 830 | 25/270 | — | 11/122 | 5.6 | — | — | ||||
| Bülow et al. (1994) | 29 | Laser | — | — | — | — | — | — | — | 15 min-3/w-9 | The positive effect of treatment is likely to be due to a placebo effect |
| Gur et al. (2003) | 90 | Laser | 904 | 10 | 1 | — | — | — | 2 | 5 min-5/w-10 | Significant improvements in pain, function, and quality of life |
| Laser | 904 | 11.2 | 1 | — | — | — | 2 | 3 min-5/w-10 | |||
| Tascioglu et al. (2004) | 60 | Laser | 830 | 50 | Diameter = 1 mm | — | — | 3 | 5 | 2 min/point-5/w-10 | No significant improvement is observed |
| Laser | 830 | 50 | Diameter = 1 mm | — | — | 1.5 | 5 | 1 min/point-5/w-10 | |||
| Yurtkuran et al. (2007) | 55 | Laser | 904 | 4 | — | 10 | 1.2 | 0.48 | 10 | 2 min/point-5/w-10 | Effective only in reducing periarticular swelling |
| Fukuda et al. (2011) | 47 | Laser | 904 | 60 | 0.5 | 120 | 6 | 3 | 9 | 50 s/point-3/w-9 | PBMT significantly improves pain and function over the short term |
| Alfredo et al. (2012) | 40 | Laser | 904 | 60 | 0.5 | — | 6 | 3 | 9 | 50 s/point-3/w-9 | PBMT associated with exercises is effective in yielding pain relief, function and activity |
| Gworys et al. (2012) | 94 | Laser | 810 | 400 | 0.63 | 634.9 | 12.7 | 8 | 12 | 20 s/point-5/w-10 | Significant improvements in knee joint function and pain relief |
| 808 + 905 | 1,100 | 2 | — | 6.21 | 12.4 | 12 | 20 s/point-5/w-10 | ||||
| 808 + 905 | 1,100 | 2 | — | 3.28 | 6.6 | 12 | 20 s/point-5/w-10 | ||||
| Hsieh et al. (2012) | 72 | Laser | 890 | 6,240 | 180 | 34.7 | 41.6 | — | 8 | 40 min-3/w-6 | No beneficial effect in improving pain, physical activity, and postural stability is observed |
| Al Rashoud et al. (2014) | 49 | Laser | 830 | 30 | 0.28 | 4 | 1.2 | 5 | 40 s/point-?-9 | Short-term application of PBMT to specific acupuncture points in association with exercise or advice effectively relieves pain and improves quality of life | |
| Alghadir et al. (2014) | 40 | Laser | 850 | 50 | Diameter = 1 mm | — | 48 | 6 | 8 | 60 s/point-2/w-8 | Effective in short-term pain relief and function improvement |
| Hinman et al. (2014) | 282 | — | — | 10 | — | — | — | 0.2 | 6 | 20 min-1 or 2/w-8∼12 | No significant improvements are observed |
| Kheshie et al. (2014) | 53 | Laser | 830 | 800 | — | 25.6 | 50 | 1,250 | — | 1,953 s-2/w-12 | Effective in improving pain and function |
| Helianthi et al. (2016) | 62 | Laser | 785 | 50 | — | 25 | 2 | 4 | 5 | 80 s/point-2/w-10 | Effective in reducing pain |
| Alfredo et al. (2018) | 40 | Laser | 904 | — | — | — | — | 3 | — | ?-3/w-10 | The immediate post-intervention improvements of PBMT plus strengthening exercises are maintained for 6 months |
| Braghin et al. (2019) | 60 | Laser | 808 | 100 | 0.028 | — | 200 | 5.6 | 10 | ?-2/w-15 | Combination of PBMT and exercise provides the best results for gait performance |
| Vassão et al. (2020a) | 33 | Laser | 808 | 100 | 0.05 | 2000 | 91 | 4 | 14 | 40 s/point-2/w-16 | PBMT does not optimize the effects of the exercise program |
| Vassão et al. (2020b) | 62 | Laser | 808 | 100 | 0.05 | 2000 | 91 | 4 | 14 | 40 s/point-2/w-16 | PBMT shows analgesic effects |
| Stausholm et al. (2022) | 50 | Laser | 904 | 60 | — | — | — | 3 | 15 | 50 s/point-3/w-9 | PBMT significantly reduces pain and provides a positive add-on effect in the follow-up period |
| Ahmad et al. (2023) | 34 | Laser | 830 | 400 | 20 | — | 10–12 | — | — | 15 min-1/w-12 | Incorporating HILT as an adjunct is more effective than PBMT in the improvements of pain, physical function and knee-related disability |
| Jankaew et al. (2023) | 47 | Laser | 808/660 | 300 | — | — | — | — | 6 | 15 min-3/w-24 | Significantly improves muscle strength and functional performance |