Measurements of Non-Injurious Head Accelerations of Young Children

Few studies have investigated pediatric head injury mechanics with subjects below the age of 8 years. This paper presents non-injurious head accelerations during various activities for young children (2 to 7 years old). Eight males and five females aged 2-7 years old were equipped with a head sensor package and head kinematics were measured while performing a series of playground-type activities. The maximum peak resultant accelerations were 29.5 G and 2745 rad/s². The range of peak accelerations was 2.7 G to 29.5 G. The range of peak angular velocities was 4.2 rad/s to 22.4 rad/s. The range of peak angular accelerations was 174 rad/s² to 2745 rad/s². Mean peak resultant values across all participants and activities were 13.8 G (range 2.4 G to 13.8 G), 12.8 rad/s (range 4.0 rad/s to 12.8 rad/s), and 1375 rad/s² (range 105 rad/s² to 1375 rad/s²) for linear acceleration, angular velocity, and angular acceleration, respectively. The peak accelerations measured in this study were similar to older children performing similar tasks. As in older children and adults, there was no difference between male and female subjects in terms of head kinematics values. The present study increases the upper limit of known non-injurious activities and closes the gap between the lower limit of injurious loading and the upper limit of non-injurious loading.