Short Term Effects of a Pectoralis Minor Positional Release in Collegiate Swimmers

Abstract

The shortened pectoralis minor directly correlates to abnormal scapular kinematics, which can cause pain, loss of range of motion and even loss of function. With these muscular imbalances causing forward scapular posture, the pectoralis minor is a key component to address in the prevention and treatment of shoulder impingement and scapular dyskinesis. This study investigated the effectiveness of a single positional release therapy (PRT) treatment of the pectoralis minor on scapular posture in collegiate swimmers immediately and 24 hours post intervention. Seventeen Division III collegiate swimmers (7 males and 10 females) volunteered to participate in this case series, with only one shoulder being excluded due to recent injury (n=33). Researchers measured resting pectoralis minor muscle length, forward shoulder posture and scapular elevation. Data measurements were collected a total of 3 times; prior to the PRT intervention, right after the intervention and again 24 hours post intervention. Each shoulder was treated with a single session of PRT on the pectoralis minor. Scapular positioning at 90° of abduction had a statistically significant increase in position from baseline to immediate post-intervention (p=.042). For forward shoulder posture, there was a statistically significant improvement in position from baseline to immediate post- intervention (p≤.001). The results of this case series show that a single treatment of PRT has an immediate effect in reducing resting pectoralis minor muscle length and decreasing rounded shoulder posture. However, this single treatment of PRT was not enough to maintain these effects after 24 hours, and should be combined with other manual therapies or rehabilitation protocols to address scapular dyskinesis in collegiate swimmers.