title: Detection of concussion using cranial accelerometry.
abstract: OBJECTIVE
  To determine whether skull motion produced by pulsatile cerebral blood flow, as measured by cranial accelerometry, is altered during concussion.
  
  
  METHODS
  In phase 1, to identify a specific pattern indicative of concussion, cranial accelerometry of subjects who sustained a concussion underwent analysis of waveforms, which was compared with accelerometry from subjects without a concussion (baseline). In phase 2, this concussion pattern was tested against prospectively acquired, blinded data.
  
  
  METHODS
  High school tackle football practice and game play.
  
  
  METHODS
  Eighty-four football players.
  
  
  METHODS
  Subjects had accelerometry measurements and concurrent 2-lead electrocardiograms. In players with a concussion, multiple sequential measurements were obtained. Sport Concussion Assessment Tool 2 was used to assist clinical determination of concussion.
  
  
  METHODS
  Whether a characteristic waveform pattern of cranial accelerometry occurs in subjects with concussion.
  
  
  RESULTS
  Phase 1 demonstrated a consistent pattern correlated to concussion. Phase 2 found this pattern in 10 of 13 subjects with concussion (76.9% sensitivity). Seventy-nine of 82 baseline plus nine postseason (total = 91) recordings from nonconcussed subjects did not show the concussion pattern (87% specificity).
  
  
  CONCLUSIONS
  In subjects with concussion, we observed a unique pattern determined by cranial accelerometry. This may provide a method to noninvasively detect and longitudinally observe concussion.
  
  
  CONCLUSIONS
  There is no objective, real-time, noninvasive, and easily accessible measure for concussion. If accelerometry is validated, it could provide a critical diagnostic tool for sports medicine physicians.
authors.affiliation: *Division of Emergency Medicine, Department of Surgery, Stanford University School of Medicine, Stanford, California; †Department of Orthopedic Surgery, Stanford University School of Medicine, Stanford, California; ‡Stanford-Kaiser Affiliated Residency in Emergency Medicine, Stanford University School of Medicine, Stanford, California; §Los Altos High School, Los Altos, California; and ¶Department of Neurology, School of Medicine, University of California, San Francisco, San Francisco, California.
authors.forename: Paul S
authors.initials: PS
authors.lastname: Auerbach
authors.forename: Jennifer G
authors.initials: JG
authors.lastname: Baine
authors.forename: Megan L
authors.initials: ML
authors.lastname: Schott
authors.forename: Amy
authors.initials: A
authors.lastname: Greenhaw
authors.forename: Monika G
authors.initials: MG
authors.lastname: Acharya
authors.forename: Wade S
authors.initials: WS
authors.lastname: Smith
mesh_terms: D061725:Accelerometry / Q000379:methods*; D000293:Adolescent; D000465:Algorithms; D001924:Brain Concussion / Q000175:diagnosis*; D002560:Cerebrovascular Circulation / Q000502:physiology*; D005538:Football / Q000293:injuries*; D006801:Humans; D008297:Male; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D012886:Skull / Q000503:physiopathology*