title: Predictors of throwing velocity in youth and adolescent pitchers.
abstract: BACKGROUND
  Shoulder and elbow injuries are a common cause of pain, dysfunction, and inability to play in overhead throwers. Pitch velocity plays an integral part in the etiology of these injuries; however, the demographic and biomechanical correlates with throwing velocity remain poorly understood. We hypothesized that pitchers with higher velocity would have shared demographic and kinematic characteristics.
  
  
  METHODS
  Normal preseason youth and adolescent pitchers underwent dual-orthogonal high-speed video analysis while pitch velocity was collected with a radar gun. Demographic and pitching history data were also collected. Kinematic data and observational mechanics were recorded. Multivariate regression analysis was performed.
  
  
  RESULTS
  A total of 420 pitchers were included, with a mean pitching velocity of 64 ± 10 mph. After multivariate logistic regression analysis, the most important correlates with pitch velocity were age (P < .001; R(2) = 0.658), height (P < .001; R(2) = 0.076), separation of the hips and shoulders (P < .001; R(2) = 0.027), and stride length (P < .001; R(2) = 0.016); in combination, these 4 variables explained 78% of the variance in pitch velocity. Each year of age was associated with a mean 1.5 mph increase in velocity; each inch in height, with 1.2 mph; separation of the hips and shoulders, with 2.6 mph; and a 10% increase in stride length, with 1.9 mph.
  
  
  CONCLUSIONS
  Pitch velocity is most strongly correlated with age, height, separation of the hips and shoulders, and stride length.
authors.affiliation: Accelerated Rehabilitation Centers Ltd, Chicago, IL, USA.
authors.forename: Terrance
authors.initials: T
authors.lastname: Sgroi
authors.affiliation: Department of Orthopaedic Surgery, Rush University Medical Center, Chicago, IL, USA. Electronic address: p.n.chalmers@gmail.com.
authors.forename: Peter N
authors.initials: PN
authors.lastname: Chalmers
authors.affiliation: Department of Orthopaedic Surgery, Rush University Medical Center, Chicago, IL, USA.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Riff
authors.affiliation: Accelerated Rehabilitation Centers Ltd, Chicago, IL, USA.
authors.forename: Matthew
authors.initials: M
authors.lastname: Lesniak
authors.affiliation: College of Physicians and Surgeons, Columbia University, New York, NY, USA.
authors.forename: Eli T
authors.initials: ET
authors.lastname: Sayegh
authors.affiliation: Department of Orthopaedic Surgery, Rush University Medical Center, Chicago, IL, USA.
authors.forename: Markus A
authors.initials: MA
authors.lastname: Wimmer
authors.affiliation: Department of Orthopaedic Surgery, Rush University Medical Center, Chicago, IL, USA.
authors.forename: Nikhil N
authors.initials: NN
authors.lastname: Verma
authors.affiliation: Department of Orthopaedic Surgery, Rush University Medical Center, Chicago, IL, USA.
authors.forename: Brian J
authors.initials: BJ
authors.lastname: Cole
authors.affiliation: Department of Orthopaedic Surgery, Rush University Medical Center, Chicago, IL, USA.
authors.forename: Anthony A
authors.initials: AA
authors.lastname: Romeo
mesh_terms: D000293:Adolescent; D000367:Age Factors; D001484:Baseball / Q000502:physiology*; D001696:Biomechanical Phenomena; D001827:Body Height / Q000502:physiology; D002648:Child; D003430:Cross-Sectional Studies; D004551:Elbow Joint / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D009068:Movement / Q000502:physiology; D011187:Posture / Q000502:physiology; D016059:Range of Motion, Articular; D012785:Shoulder Joint / Q000502:physiology*; D014741:Video Recording
keywords: Baseball; injury prevention; motion analysis; overhand throwing; pitching; superior labral anterior-posterior tear; ulnar collateral ligament tear