Research highlights potential cause of pitching injuries going overlooked

Jason Zaremski, MD presented a research abstract about the importance of considering practice and warm-up pitches in total pitch counts at the 27th Annual Meeting of the American Medical Society for Sports Medicine in Lake Buena Vista, FL. The presentation was selected for the Best Overall Research Award during the meeting.

Throwing injuries are common in baseball and can be caused by excessive pitch counts, year-round pitching, and pitching with arm pain and fatigue. Despite the evidence, pitching injuries among high school players have not decreased, and Dr. Zaremski and his team conducted research to determine whether an important factor was being overlooked: warm-up pitches and bullpen activity.

The research team hypothesized that high school pitchers could exceed the recommended pitch count guidelines by about 30-40% when including bullpen sessions and warm-up pitches -; adding a considerable amount of pitches that weren't being accurately counted.

With a multitude of research in overhead throwers, yet the volume of overuse throwing injuries not decreasing, our team suspected there was a missing workload factor in baseball pitchers," Dr. Zaremski said.

In the study, researchers counted all pitches thrown off a mound during varsity high school baseball games played by 34 different high schools in North Central Florida during the 2017 season.

Dr. Zaremski and his team found that 42% of the pitches thrown off a mound were not accounted for in the pitch counts, and that there is a large variability of bullpen pitches being thrown. Even with a greater focus on pitch counts as a way to prevent injuries, a substantial part of pitches are going unaccounted for in high school players as part of warm-up and bullpen activity.

Close monitoring of these extra pitches should occur to help limit the risk of overuse injuries, and this study could potentially lead to novel off-season and in-season training recommendations in high-school aged pitchers.

"Our findings suggest that close monitoring of all pitches thrown off a mound should be included for accurate documentation volume workload in high school baseball pitchers," Dr. Zaremski said.