This paper describes the risk of the knee joint injury for belted car drivers in traffic accidents. The situation for knee injuries has been influenced by the changing of interior design of vehicles, including the dashboard and restraint systems like seatbelts, pretensioners and airbags over recent decades. An analysis of real world accidents was carried out by utilizing accident data gathered under the in-depth-investigation methodology practiced by the GIDAS (German-In-Depth-Accident-Study) multi-disciplinary research team. GIDAS document accidents on-the-spot, using a sampling process to ensure that results are representative for the German traffic accident situation. Accident documentations from 1985 to 2003 are used for thisstudy. Two different groups of accident data were compared: the years 1985 to 1993 (n=536 people with knee injury rated AIS1, n=81 people with kneeinjury rated AIS2+, n= 7260 injured people without knee injury), and 1995to 2003 (n=451 people with knee injury rated AIS1, n=48 people with knee injury rated AIS2+, n= 9372 injured people without knee injury). The studydescribes the frequencies of knee injuries on soft tissue knee lesions rated AIS1 and injuries to ligaments and fractures rated AIS2+. In addition,knee injury risks are evaluated by comparing results with the group of drivers without knee injury. The study shows that there is, nowadays, a low risk of severe knee injuries rated AIS 2+ for seat-belted car drivers (0.4% of all injured drivers, documented years 1995 to 2003). It can be pointed out comparing the results with previous studies, that knee injury risk for belted drivers in German car accidents is much lower than that expected from investigations in other countries. The classical dashboard injury that could be seen in the past, very often involving fractures of the acetabulum plus patella plus rupture of rear cruciate ligament can no longer beseen in accidents today. A fracture of the patella could be established in the current accident sample for only 0.1% of all injured belted car drivers. Patella fractures are an indicator of axial load, observed in 43% of the AIS2+ knee injury cases (n=44). The number of patella fractures is directly proportional to delta-v and intrusion. A femur fracture was found in25 %, and a fracture of the acetabulum was found in 5 % of the knee injured cases. Ruptures of the cruciate ligaments are observed relatively seldom (7.5% of AIS2+ knee injured occupants). These results indicate a good level of passive safety in cars today. For the covering abstract see ITRD E141569.
Abstract