Most of the collisions occurred in the cities of Tsukuba and Tsuchiura between April 1993 and March 1998. Results of the analysis revealed that the cases involved 33 flat-front vehicles and 68 bonnet-front vehicles. Chest injuries occurred in 30.3 percent of the flat-front cases and 11.8 percent of the bonnet-front cases. This difference was significant. However, lower-leg fractures were more common on bonnet-front injuries. Head injuries were common in both situations, but the mechanisms of these injuries differed. The pedestrians struck by flat-front vehicles tended to sustain more severe injuries at lower impact speeds than did those struck by bonnet-front injuries. All these results stemmed from the differences in the front shapes of the two types of vehicle. In addition, impact speed was one of the most important factors influencing the severity of pedestrian injuries. Overall, pedestrians struck by the front of flat-front vehicles received the impact force to the trunk, particularly the chest, at the initial impact and were thrown out forward after the impact, because the fronts of these vehicles were perpendicular to the road. The analysis concluded that the characteristics of pedestrian injuries caused by flat-front vehicles differ from those caused by bonnet-front vehicles and that these findings may aid medical personnel in determining the location and degree of injuries and in planning life support strategies. Figures, tables, and 15 references (Author abstract modified)