The prevalence of myofascial trigger points in asymptomatic overhead athletes

The purpose of this study was to determine the prevalence myofascial trigger points (TPs) in asymptomatic overhead athletes. Glenohumeral rotation range of motion (ROM) of fifteen participants was measured on both the dominant and non-dominant arm. Following the ROM measures a second examiner, blinded to the ROM measurements, palpated for seven TPs in four muscles of the posterior shoulder: the posterior deltoid (1 TP), infraspinatus (3TPs), teres minor (1 TP), and latissimus dorsi (2 TP). These muscles apply braking force to assist in the deceleration of the upper extremity in order to prevent translation of the proximal humerus at the glenoid fossa (Borsa, Laudner, & Sauers, 2008). Chi-square tests were used to assess differences in prevalence of MTrPs between dominant and non-dominant arm. An alpha level of .05 was set a priori for all tests of significance. All analyses will be done with SPSS (V. 21, Chicago, IL). No significant differences (P>.05) were found between dominant and non-dominant arm, although a trend was noted with the trigger point identified in the infraspinatus (superior), which yielded a P value of 0.069. The results suggest a relationship between decreased ROM and the prevalence of trigger points. All the participants had at least one trigger point. The assessment and treatment of trigger points may be necessary when examining the shoulder for potential injury and (or) decrease in performance.