ABSTRACT
BACKGROUND: Repetitive trauma to the hand is a concern for baseball players. The present study investigated the effects of repetitive trauma and the prevalence of microvascular pathological changes in the hands of minor league professional baseball players. In contrast to previous investigators, we documented the presence of abnormalities in younger, asymptomatic individuals. METHODS: Thirty-six baseball players on active minor league rosters underwent a history and physical examination of both hands as well as additional specialized tests, including Doppler ultrasound, a timed Allen test, determination of digital brachial pressure indices, and ring sizing of fingers. Data were compared between gloved hands and throwing hands, hitters and nonhitters, and players at four different positions (catcher [nine subjects], outfielder [seven subjects], infielder [five subjects], and pitcher [fifteen subjects]). RESULTS: Digital brachial indices in the ring fingers of the gloved (p < 0.05) and throwing hands (p < 0.02) of catchers were significantly diminished compared with those in all other players. Doppler testing showed a significantly greater prevalence of abnormal flow in the ulnar artery at Guyon's canal when catchers were compared with other position players (p < 0.01). Doppler abnormalities were significantly more common in the gloved hand compared with the throwing hand (p < 0.05). Seven of nine catchers (and only catchers) were found to have index finger hypertrophy (average change, two ring sizes; p < 0.01); the hypertrophy occurred at the proximal phalanx and the proximal interphalangeal joint of the gloved hand. Catchers had a significantly higher prevalence of subjective hand symptoms (specifically, weakness in the gloved hand) compared with pitchers and infielders/outfielders (44% compared with 7% and 17%, respectively; p < 0.05). CONCLUSIONS: Microvascular changes are present in the hands of otherwise healthy professional baseball players in all positions, with a significantly higher prevalence in catchers, prior to the development of clinically important ischemia. Repetitive trauma resulting from the impact of the baseball also leads to digital hypertrophy in the index finger of the gloved hand of catchers. Gloves currently used by professional catchers do not adequately protect the hand from repetitive trauma.
