title: Analysis of the ability of catcher's masks to attenuate head accelerations on impact with a baseball.
abstract: OBJECTIVE
  The goals of this study were to measure the ability of catcher's masks to attenuate head accelerations on impact with a baseball and to compare these head accelerations to established injury thresholds for mild traumatic brain injury.
  
  
  METHODS
  Testing involved using a pneumatic cannon to shoot baseballs at an instrumented Hybrid III headform (a 50th percentile male head and neck) with and without a catcher's mask on the head. The ball speed was controlled from approximately 26.8 to 35.8 m/s (60-80 mph), and the regulation National Collegiate Athletic Association baseballs were used.
  
  
  METHODS
  Research laboratory.
  
  
  METHODS
  None.
  
  
  METHODS
  Catcher's masks and impact velocity.
  
  
  METHODS
  The linear and angular head accelerations of the Hybrid III headform.
  
  
  RESULTS
  Peak linear resultant acceleration was 140 to 180 g without a mask and 16 to 30 g with a mask over the range of ball's speed investigated. Peak angular resultant acceleration was 19 500 to 25 700 rad/s without a mask and 2250 to 3230 rad/s with a mask. The Head Injury Criterion was 93 to 181 without a mask and 3 to 13 with a mask, and the Severity Index was 110 to 210 without a mask and 3 to 15 with a mask.
  
  
  CONCLUSIONS
  Catcher's masks reduced head acceleration metrics by approximately 85%. Head acceleration metrics with a catcher's mask were significantly lower than contemporary injury thresholds, yet reports in the mass media clearly indicate that baseball impacts to the mask still occasionally result in mild traumatic brain injuries. Further research is needed to address this apparent contradiction.
authors.affiliation: Department of Engineering Science and Mechanics, Virginia Tech, Blacksburg, Virginia, USA.
authors.forename: Kellen S
authors.initials: KS
authors.lastname: Shain
authors.forename: Michael L
authors.initials: ML
authors.lastname: Madigan
authors.forename: Steven
authors.initials: S
authors.lastname: Rowson
authors.forename: Jill
authors.initials: J
authors.lastname: Bisplinghoff
authors.forename: Stefan M
authors.initials: SM
authors.lastname: Duma
mesh_terms: D000054:Acceleration; D000328:Adult; D001484:Baseball / Q000293:injuries*; D001930:Brain Injuries / Q000517:prevention & control*; D006260:Head Protective Devices; D006801:Humans; D008297:Male; D008397:Masks; D008954:Models, Biological; D012720:Severity of Illness Index; D019876:Sports Equipment