Acute Effects of Pectoralis Minor Self-Mobilization on Shoulder Motion and Posture: A Blinded and Randomized Placebo-Controlled Study in Asymptomatic Individuals

Abstract

Context: Tightness of the pectoralis minor is a common characteristic that has been associated with aberrant posture and shoulder pathology. Determining conservative treatment techniques for maintaining and lengthening this muscle is critical. Although some gross stretching techniques have been proven effective, there are currently no empirical data regarding the effectiveness of self-myofascial release for treating tightness of this muscle. Objective: To determine the acute effectiveness of a self-myofascial release with movement technique of the pectoralis minor for improving shoulder motion and posture among asymptomatic individuals. Design: Randomized controlled trial. Setting: Orthopedic rehabilitation clinic. Participants: A total of 21 physically active, college-aged individuals without shoulder pain volunteered to participate in this study. Main Outcome Measures: Glenohumeral internal rotation, external rotation, and flexion range of motion (ROM), pectoralis minor length, and forward scapular posture were measured in all participants. The intervention group received one application of a self-soft-tissue mobilization of the pectoralis minor with movement. The placebo group completed the same motions as the intervention group, but with minimal pressure applied to the xiphoid process. Separate analyses of covariance were used to determine differences between groups (P < .05). Results: Separate analyses of covariance showed that the self-mobilization group had significantly more flexion ROM, pectoralis minor length, and less forward scapular posture posttest than the placebo group. However, the difference in forward scapular posture may not be clinically significant. No differences were found between groups for external or internal rotation ROM. Conclusions: The results of this study indicate that an acute self-myofascial release with movement is effective for improving glenohumeral flexion ROM and pectoralis minor length, and may assist with forward scapular posture. Clinicians should consider this self-mobilization in the prevention and rehabilitation of pathologies associated with shortness of the pectoralis minor.