Background: The aim of our study was to analyze the injury mechanism of upper extremity fractures in car crashes, to create a basis for developing prophylactic devices.
Methods and results: During 1985-1995, 3,260 restrained car drivers (1,228 front-seat passengers) were injured in 9,380 crashes involving cars. A total of 179 drivers (5.5%) (front-seat passengers: n = 53, 4.3%) sustained fractures of the arm. The hand (25%), wrist (23%), and forearm (23%) were affected most often, and the elbow (9%), upper arm (10%), and shoulder (10%) were seldom affected. No considerable differences of the injury mechanism were found comparing drivers with front-seat passengers. Fractures were mainly caused by head-on collisions (n = 119, 51%) or multiple collisions (n = 78, 34%). In 73% of the crashes (n = 166), delta-v exceeded 30 km/h (18.6 mph). A lower Delta-v resulted mainly in fractures affecting the shoulder and wrist.
Conclusion: Because more than half of the upper extremity fractures resulted from a direct impact to the hand, arm, or both, modifications to improve the energy absorption by padding dashboard and inner door or by additional airbags are promising.