This dissertation investigated the potential for longitudinal studies to address baseball pitcher arm health. Specifically, the dissertation aimed to: (1) describe the injury epidemiology, functional and musculoskeletal (MSK) clinical outcomes, and implementation outcomes in a cohort of summer league baseball pitchers; (2) identify perspectives of pitchers and support staff in the adoption of a novel longitudinal screening and testing program addressing pitcher arm health over one summer season; (3) illustrate the use of a causal inference method known as g-computation in a sports medicine setting. In Aim 1, nearly two-thirds of players reported a MSK complaint over a single summer league season (8-12 weeks). This highlights the need to screen pitchers longitudinally with a long-term goal of rapidly addressing pain or functional deficit changes across a season. However, participation in screening systems can be variable. In particular, we found that there was higher compliance for screening tools that utilized in-person clinical tests and measures administered on a monthly basis, and lower compliance for self-administered questionnaire administered on a weekly basis. Aim 2 explored these compliance issues in more detail using qualitative methods, and resulted in the construction of six themes that highlight the importance of organizational endorsement that signals unequivocal legitimacy to facilitate participation and compliance among athletes. Themes also highlighted the importance of addressing logistical challenges to longitudinal measures. Another theme was the importance of individualized feedback from the screening tools that provided a tangible product to the athletes that represented a definable and personalized return on the investment of athlete time. Given the complexities of conducting such studies, it is important to maximize the return on the investment in observational studies. Aim 3 illustrated how commonly collected musculoskeletal clinical measures, specifically shoulder girdle range of motion (ROM), could be analyzed through g-computation to address causal research questions. We examined two causal research questions: the first one examined the causal effect on injury risk due to the introduction of an organizational screening intervention for all pitchers versus no implementation of the intervention while the second causal research question addressed the combined (joint) effects of a shoulder girdle ROM intervention on injury risk, relative to natural course. Both sets of causal analyses supported a reduction in seasonal arm injuries. Results from the three Aims support the potential for preventing arm injury through ongoing monitoring of simple clinical tests such as monthly assessments or pre-season screening protocols with corresponding interventions.
Chelsea Leonard Martin (Fri,) studied this question.