POSITIONING AND BRACING OF THE LOWER LEG DURING EMERGENCY BRAKING - A VOLUNTEER STUDY

Lower leg injuries in road traffic accidents are increasingly being recognised as an important cause of both serious and long term impairment. The mechanism of lower leg injury is considered to be significantly affected by the position of the foot, and the degree of muscular bracing of the lower leg prior to an impact. To provide a quantifiable measure of bracing and of foot and ankle position during an emergency braking event, twenty four human volunteers each undertook a 30 minute driving task on the TRL driving simulator. During the simulation each volunteer was confronted with two different emergency events requiring sudden braking. The degree of dorsi flexion/plantar flexion of the driver's right foot was measured by an electronic goniometer. Two hidden infra-red video cameras recorded the postion of the driver's feet throughout the drive. The brake pedal force was measured to allow the applied fore foot force to be calculated. The paper presents the measured values of applied brake pedal force and the orientation of the feet during the 'impact' event, and draws conclusions about the implications for foot and ankle injury in crashes. (A) For the covering abstract see ITRD E106363.