Dual Frequency Low-Level Laser Therapy in Myofascial Trigger Points of Upper Trapezius

DF-LLLT (830 nm, 100 mW/cm², 9.12 Hz, 5 J/cm²) applied over each identified trigger point for 3 minutes 9 seconds per point, twice weekly for 4 weeks.

Inactive laser device identical in appearance and sound to the active laser but without light emission, applied for 3 minutes 9 seconds per point, twice weekly for 4 weeks.

A standardized physiotherapy program including stretching and strengthening exercises for the cervical and shoulder muscles. The program is performed under physiotherapist supervision twice weekly for 4 weeks. Exercises are identical across both study arms and include stretching of the upper trapezius and strengthening of the neck and scapular stabilizer muscles.