Correlation of bone density and rib fractures

More information

Main author

Tomasch, E.

Co-Authors

Sinz, W.; Kirschbichler, S; Steffan, H.; Darok, M.; Patsch, J.; Dimai, H.-P.

Type of media

PDF

Publication type

Lecture

Publication year

2011

Publisher

20. EVU Conference, Graz

Citation

Tomasch, E.: Correlation of bone density and rib fractures. 20. EVU Conference, Gratz

In traffic accidents, very often serious internal injuries in the thoracic area can come about, which can also be fatal. Due to the high acceleration loads during a road accident, rib fractures often occur. This is especially noted for older occupants. The mechanical properties of the human body change during the course of life, whereas the stiffness of the chest of newborns is very pliable and increases with age. Yet a decrease in stiffness can be seen for older persons. The bony ribs are brittle with age, increasing the risk of rib fractures. For the development of adaptive restraint systems, which allow an optimal protection of young and elderly passengers further biomechanical data are therefore necessary for the design process. However, the different biomechanical behaviour of young and old people, the development of intelligent restraint systems poses major challenges. The use of human models allows a more detailed account of the human biomechanics for the design processes in automotive safety. However, this is a good validation of human models in advance so they can map the human person as possible. Further validation of human models requires the determination of possible biomechanical limits for young and old vehicle occupants therefore force-displacement curves from samples of different areas (anterior, lateral and posterior) post-mortem human rib from human surrogates have been determined. Previously the bone mineral density and geometric dimensions (width, height, and curvature) had been determined from each sample. The results showed on the one hand, an increase in bone mineral density from the sternum to the spine and on the other hand, the decrease in the course of life. Furthermore, a correlation could be established between force-displacement curves and the bone mineral density. Rib samples of the same geometry, but with higher bone mineral density were able to withstand a higher stress level, before there was a failure.