The main purpose of this study was to identify the effects of physical therapy modalities and exercise therapy on myofascial pain syndrome by assessing the degree of effect size (ES) and related variables.

Related studies published between 1^st January 2008 and 31^st December 2019were retrieved from national [KCI, RISS, National Assembly Library and DBpia (n = 405)] and international [PubMed, Embase, Google Scholar and Cochrane library (n = 1,600)] databases. According to the selection criteria, 25 studies were selected for review.

The degree of ES in the physical therapy and exercise therapy combined group (1.83) showed the largest mean ES. The size of the effect according to the number of people to be treated was 41 or more (1.64), and showed the largest mean ES. The size of the effect according to treatment period was 16 to 30 days (1.41). The size of the effect for 6 to 10 treatments (1.51) showed the largest mean ES. Trim and fill results showed that the calibration ES was 0.67.

Physical therapy modalities and exercise therapy had a great effect on myofascial pain syndrome in the neck and shoulders, and the effect differed according to the methods of intervention, and the methods of evaluation.