title: Decreased blood flow in the throwing arm of professional baseball pitchers.
abstract: BACKGROUND
  As a consequence of the repetitive forces placed on the throwing arm of a baseball player, various bony, capsuloligamentous, and muscular adaptations occur and have been identified. However, no research has identified whether adaptations also exist in the vasculature of the upper extremity in the competitive baseball player.
  
  
  METHODS
  Fifty-one professional baseball pitchers and 34 position players participated. Diagnostic ultrasound was used to measure bilateral blood flow of the brachial artery. These measurements were taken with the participant standing with the test arm resting at the participant's side and again with the test arm in a provocative shoulder position.
  
  
  RESULTS
  The throwing arm of the pitchers had significantly less blood flow volume when in the provocative shoulder position compared with their nonthrowing arm (P = .01). Pitchers did not have any bilateral difference while in the resting position (P = .19). There were no bilateral differences among the position players while in the resting (P = .64) or provocative positions (P = .63). Pitchers had significantly less blood flow of the throwing shoulder while in the provocative position compared with position players (P = .02). There were no other between-group differences.
  
  
  CONCLUSIONS
  While in a provocative shoulder position, pitchers have significantly less blood flow in their throwing arm compared with their nonthrowing arm and with the throwing arm of position players. These results provide a descriptive profile of blood flow volume among baseball players, which may be used in the evaluation and treatment of such athletes with vascular disorders.
authors.affiliation: Illinois State University, School of Kinesiology and Recreation, Normal, IL, USA; Texas Metroplex Institute for Sports Medicine and Orthopedics, Arlington, TX, USA. Electronic address: klaudner@ilstu.edu.
authors.forename: Kevin G
authors.initials: KG
authors.lastname: Laudner
authors.affiliation: Illinois State University, School of Kinesiology and Recreation, Normal, IL, USA.
authors.forename: Noelle M
authors.initials: NM
authors.lastname: Selkow
authors.affiliation: Illinois State University, School of Kinesiology and Recreation, Normal, IL, USA.
authors.forename: Nicholas C
authors.initials: NC
authors.lastname: Burke
authors.affiliation: Department of Exercise and Sport Science, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
authors.forename: Robert C
authors.initials: RC
authors.lastname: Lynall
authors.affiliation: Texas Metroplex Institute for Sports Medicine and Orthopedics, Arlington, TX, USA.
authors.forename: Keith
authors.initials: K
authors.lastname: Meister
mesh_terms: D000222:Adaptation, Physiological; D001484:Baseball / Q000502:physiology*; D001916:Brachial Artery / Q000000981:diagnostic imaging*; D003430:Cross-Sectional Studies; D006801:Humans; D008297:Male; D011187:Posture / Q000502:physiology; D014463:Ultrasonography; D034941:Upper Extremity / Q000098:blood supply*; D055815:Young Adult
keywords: Vasculature; throwing athlete; upper extremity