Epidemiology of acromioclavicular joint injuries in professional baseball: analysis from the Major League Baseball Health and Injury Tracking System

BackgroundShoulder injuries account for a large portion of all recorded in professional baseball. Much is known about other shoulder pathologies the overhead athlete, but incidence and impact acromioclavicular (AC) joint this population are unknown. We examined epidemiology AC Major League Baseball (MLB) Minor (MiLB) players determined on time missed.MethodsThe MLB Health Injury Tracking System was used to compile records MiLB from 2011 2017 with documented injuries. These were classified as acute (sprain or separation) chronic (AC arthritis distal clavicular osteolysis), associated data extracted included laterality, date injury, player position, activity, mechanism length return play, need surgical intervention.ResultsA total 312 (183 129 players; range, 39-60 per year) recorded: 201 (64.4%) 111 (35.6%). A 81% 59% resulted missed, mean play 21 days both. Of outfielders, 79.6% (P < .0001), 66.3% infielders = .004). Pitchers catchers had more equal proportions > .05 all). Acute occurred most often while fielding (n 100, 84.7%), running 25, 80.6%), hitting 19, 61.3%), whereas tended be common pitching 26, 68.4%). contact injuries, 82.5% 59.0% noncontact .047). showed consistently higher regular-season rates both than .0001 each).ConclusionAcute occurring commonly among outfielders that result 3 weeks missed before occur pitchers repetitive activity. Knowledge these can better guide expectation management elite elucidate prevalence 2 injury patterns joint. Shoulder missed. The intervention. each).