title: A study of adult pedestrian head impact conditions and injury risks in passenger car collisions based on real-world accident data.
abstract: OBJECTIVE
  The aim of the current study was to study the kinematics of adult pedestrians and assess head injury risks based on real-world accidents.
  
  
  METHODS
  A total of 43 passenger car versus pedestrian accidents, in which the pedestrian's head impacted the windscreen, were selected from accident databases for simulation study. According to real-world accident investigation, accident reconstructions were conducted using multibody system (MBS) pedestrian and car models under MADYMO environment (Strasbourg University) to calculate head impact conditions in terms of head impact velocity, head position, and head orientation. Pedestrian head impact conditions from MADYMO simulation results were then used to set the initial conditions in a simulation of a head striking a windscreen using finite element (FE) approach.
  
  
  RESULTS
  The results showed strong correlations between vehicle impact velocity and head contact time, throw distance, and head impact velocity using a quadratic regression model. In the selected samples, the results indicated that Abbreviated Injury Scale (AIS) 2+ and AIS 3+ severe head injuries with probability of 50 percent were caused by head impact velocity at about 33 and 49 km/h, respectively. Further, the predicted head linear acceleration (head injury criterion, HIC) value, resultant angular velocity, and resultant angular acceleration for 50 percent probability of AIS 2+ and AIS 3+ head injury risk were 116 g, 825, 40 rad/s, 11,368 rad/s(2) and 162 g, 1442, 55 rad/s, 18,775 rad/s(2), respectively, and the predicted value of 50 percent probability of skull fracture was 135 g.
  
  
  CONCLUSIONS
  The present study provides new insight into pedestrian head impact conditions in terms of velocity, angle, and impact location based on a number of real-world cases. Therefore, it may perform a critical analysis for current pedestrian head standard tests.
authors.affiliation: Key Laboratory of Traffic Safety on Track of Ministry of Education, School of Traffic and Transportation Engineering, Central South University, Changsha, China. pengyong20080708@163.com
authors.forename: Yong
authors.initials: Y
authors.lastname: Peng
authors.forename: Caroline
authors.initials: C
authors.lastname: Deck
authors.forename: Jikuang
authors.initials: J
authors.lastname: Yang
authors.forename: Dietmar
authors.initials: D
authors.lastname: Otte
authors.forename: Remy
authors.initials: R
authors.lastname: Willinger
mesh_terms: D000063:Accidents, Traffic / Q000706:statistics & numerical data*; D000328:Adult; D001696:Biomechanical Phenomena; D003198:Computer Simulation; D006259:Craniocerebral Trauma / Q000209:etiology*; D016208:Databases, Factual; D006801:Humans; D008297:Male; D018570:Risk Assessment; D016138:Walking / Q000293:injuries*; D014947:Wounds and Injuries / Q000209:etiology