Assessment of Asymmetry in Posture, Neuromuscular Function of Trunk Musculature, and Balance in Adolescent Baseball Pitchers
The purpose of this research was to assess for any asymmetries in the function of the lumbo-pelvic-hip musculature in high school and collegiate baseball pitchers. Data from fifty-six healthy pitchers between the ages of 14 and 25 who were a part of a larger study were included in this study. A battery of clinical tests that included single leg hop test, Y-balance test, isometric hip abduction strength test, isometric trunk rotation strength test, in-line lunge toss test, and side-plank test were collected and analyzed. Mean comparisons did not reveal any asymmetry in lumbo-pelvic-hip musculature function between the stride and stance leg. Except for trunk rotation strength, asymmetry in lumbo-pelvic-hip musculature function found in healthy high school and collegiate pitchers were mostly within 10%. Conversely, asymmetry exceeding 10% was found in over two thirds of the participants for the isometric trunk rotation strength test, and a subgroup of pitchers who had asymmetry due to weakness in rotating their torso towards the stride leg demonstrated poorer Y-balance test composite scores on both sides compared to pitchers with no asymmetry. Clinicians who work with baseball pitchers can use the results of our study in the interpretation of their clinical tests. Further research is warranted to explore the role that trunk rotation strength asymmetry plays in the development of injuries in baseball pitchers.