Based on physical examination of new members of high school baseball teams, No obvious association was found between the prevalence of shoulder and elbow injuries at the time of high school entry and students’ pitching experience during elementary and junior high school.
Childhood shoulder and elbow injuries due to excessive baseball pitching have been reported, and limiting the number of pitches has been recommended, particularly in children whose primary position is pitcher. While the risks of pitching are indisputable, we have experienced a large number of patients with osteochondritis dissecans (OCD) of the elbow who were fielders rather than pitchers, and who required surgery. In this study we examined the association between shoulder and elbow injuries and pitching experience, based on examinations of the shoulders and elbows of new members of high school baseball teams.
Subjects and Method
From 2012 to 2017, the orthopaedic surgeons and physical therapists examined the shoulders and elbows of 358 new members of several high school baseball teams. One hundred ninety-five students had experience as a pitcher, 55 of whom had played only rubber-ball baseball during junior high school. One hundred and sixty-three students had no experience as a pitcher, 81 of whom had played only rubber-ball baseball. Students were assigned to either the pitching group or non-pitching group to determine whether experience as a pitcher and the years of pitching experience were associated with shoulder and elbow injuries. Shoulders were diagnosed as either normal or injured (exhibiting inflammation, for instance) based on pain history and physical examination. Elbows were diagnosed as normal or having a medial elbow injury or OCD based on pain history, physical examination, and echography. For statistical analysis, the Mann-Whitney U test was used for shoulders and the Kruskal-Wallis test was used for elbows.
Shoulder injury was observed in 13.8% of subjects in the pitching group and 10.4% of those in the non-pitching group, indicating no significant difference. Among the subjects with elbow injury, the incidences of OCD, medial elbow injury, or both were 3.6%, 22.6%, and 1.5% in the pitching group, and 4.3%, 17.2%, and 0% in the non-pitching group, respectively, indicating no significant difference between the groups. The mean number of years of pitching experience was 1.74 years in the group without shoulder injury and 1.96 years in the group with shoulder injury, indicating no significant difference. Similarly, the number of years of pitching experience was 1.64 years in the group without elbow injury, 1.71 years in the group with OCD, 2.17 years in the group with medial elbow injury, and 3.67 years in the group with both OCD and medial elbow injury, indicating no significant difference.
Discussion And Conclusion
No obvious association was found between the prevalence of shoulder and elbow injuries at the time of high school entry and students’ pitching experience during elementary and junior high school. The presence or absence of pitching experience and the years of pitching experience in the OCD group were comparable to the group without injury, suggesting that pitching experience was not associated with the development of OCD. Therefore, it may be difficult to decrease children’s baseball-related shoulder and elbow injuries by conducting physical examinations of pitchers only, and examination of all child baseball players seems to be preferable.