Epidemiology, Workload, and Performance of Major League Baseball Pitchers Placed on the Disabled List

There is limited information on the effect of pitcher workload, pitch type, and performance of Major League Baseball pitchers placed on the disabled list (DL). This study evaluated demographic, performance, workload, and injury data of 330 Major League Baseball pitchers with 454 injuries who were placed on the DL during the 2014 and 2015 seasons. Upper extremity, lower extremity, core, hip/groin, and other injuries were analyzed, and injury year data were compared with career data as well as against other injury groups. Upper extremity injuries represented 60% of injuries and a mean of 61.4 (SE, 2.6) days on the DL, while lower extremity and core injuries each represented 14% of all injuries. Players with upper extremity injuries returned to play the same season at the lowest rate (67.3%). Starters pitched more mean innings per game (5.31 vs 5.14 innings, P=.012) and threw more mean pitches per game (85.9 vs 82.4 pitches, P=.003) the year of injury compared with their career. There was a decrease in mean fastball velocity (92.2 vs 91.6 mph,