The Effect of Low Power Laser Acupuncture on Experimental Pain Threshold in Normal Subjects

In This research the immediate & latent effect of low power Ga-Al-As laser irradiation applied to acupuncture points on experimental pain Threshold were studied.

Material & Method

Study design was quasi experimental, seventhy adult women Ranging in age from 20-40 years assigned randomly to one of two groups. Laser group (n=33) received L.P.L Ga-Al-As to appropriate acupuncture points for wrist pain, control group (n=37) received placebo laser, this research was single blind. We measured experimentally induced pain threshold at ipsilateral nondominant wrist following electrical stimulus, once before treatment and three times after treatment with short intervals.

Parameters for laser were, wavelength , 780 nm; power out put, 5mw and acupuncture points; L.I.4 & L.I.5 each point was treated for 60 sec which amounted to 0.3 j/point, radiation technique was direct contact. Parameters for electrical stimulus were, monophase squar wave with a duration of 5 ms; interpuls interval, 500 ms and intensity , 0-30 mA.

Results

The laser group demonstrated a statistically significant (p=0.001) increase in mean value for pain threshold at 10 minuts after treatment, but control group did not Also changes of pain threshold in laser group were greater than of control group. This increase remained significant only at 10 minuts after treatment measurments (p=0.001).

Conclusion

Low power Ga-Al-As laser radiation to acupuncture points can increase experimentally induced pain Threshold.