High Intensity Laser Therapy (HILT) on Myofascial Trigger Points.

The aim of the study is to evaluate the effects of HILT on cervical flexibility and pain reduction in myofascial trigger points. The research will be carried out in the Physiotherapy laboratory of Andrés Bello University. The participants will be civil servants and volunteer university students with the presence of latent MTrPs of the upper trapezius muscle. Participants will be randomized and divided into 3 study groups: group 1 (HILT and stretching exercises), group 2 (sham HILT and stretching exercises), and group 3 (the conventional US and stretching exercises). The treatments will be carried out twice a week for 4 weeks accompanied by 2 evaluations during the treatment and 1 post-treatment follow-up. The main result will be considered the differences in pain intensity (ΔPI), pain pressure threshold (ΔPPT), cervical spine range (ΔCROM), and cervical disability (ΔND) between the evaluation sessions.