Curriero, Frank C.

Objective: To generate a summative report on the most commonly diagnosed illnesses in Major League Baseball (MLB) and Minor League Baseball (MiLB) athletes with specific attention to their impact based on time out of play. Design: Retrospective analysis. Setting: Injury and illness data from the MLB Health and Injury Tracking System. Participants: All MLB and MiLB athletes active between 2011 and 2016. Assessment of Risk Factors: Illnesses were defined as atraumatic medical diagnoses that occurred during the MLB or MiLB season and resulted in at least 1 day out of play. Main Outcome Measures: Incidence of illness diagnoses and resulting time out play. Results: Eight thousand eight hundred thirty-four illnesses were reported, representing 14.7% of all diagnoses resulting in time out of play. Total days missed (DM) due to illness were 39 614, with a mean of 4.6 (SD 9.9 days) and median 2 DM per diagnosis. The annual incidence of illness per season was 20.3 per 100 athletes. The most common diagnosis was nonspecific viral illness (15.3%), followed by gastroenteritis (13.6%), other gastrointestinal illness (8.3%), influenza (7.0%), and upper respiratory infection (6.2%). Appendicitis (15.2%) and Epstein–Barr virus/cytomegalovirus (9.1%) were the most common season-ending diagnoses. Conclusions: Illnesses represent a significant cause of time out of play in MLB and MiLB. Prevention efforts should focus on limiting the spread of communicable viral, respiratory, and gastrointestinal disease among players, as the majority of diagnoses fell into these categories. This work may be used to guide future research into illness treatment and prevention in professional baseball.

Background: Although sliding occurs frequently in professional baseball, little is known about the epidemiology and effect of injuries that occur during sliding in this population of elite athletes. Purpose: To describe the incidence and characteristics of sliding injuries, determine their effect in terms of time out of play, and identify common injury patterns that may represent appropriate targets for injury prevention programs in the future. Study Design: Descriptive epidemiologic study. Methods: All offensive sliding injuries occurring in Major League Baseball (MLB) and Minor League Baseball (MLB) that resulted in time out of play during a span of 5 seasons (2011-2015) were identified. In addition to player demographics, data extracted included time out of play, location on field where injury occurred, level of play, treatment (surgical vs nonsurgical), direction of slide (head vs feet first), body region injured, and diagnosis. Descriptive statistics were used to describe the distribution of these injuries, and injury rates were calculated per slide. Results: From 2011 to 2015, 1633 injuries occurred as a result of a slide. The total number of days missed per season was 4263. Surgical intervention was required for 134 (8.2%) injuries, and the mean days missed was 66.5 for players treated surgically and 12.3 days for players treated nonoperatively ( P < .001). MLB players were more likely than MiLB players to require surgical intervention (12.3% vs 7.5%, P = .019). Injuries to the hands/fingers represented 25.3% of all injuries and 31.3% of those requiring surgery. Although the majority of injuries occurred at second base (57%), the per-slide injury rate was similar across all bases ( P = .991). The estimated overall frequency of injury in MLB was once per every 336 slides, and the rate of injury for head- and feet-first slides was 1 in 249 and 413 slides, respectively ( P = .119). Conclusion: Injuries occurring while sliding in professional baseball result in a significant amount of time out of play for these elite athletes. Injuries occurring at second base and those occurring to the hands and fingers were most prevalent and may be an appropriate target for future injury prevention programs.