Flexural stress waves responses on human femoral cortical bone

Abstract

The response of human femoral cortical bone to lateral impact were investigated both analytically and experimentally. In the analytical part of this investigation the Timoshenko beam theory was used for predicting the propagation of flexural stress waves along the specimens. The final solution was given in integral form and the results were obtained with the aid of a digital computer. In the experimental part of this investigation the employed specimens were obtained by cutting a human femur shaft along its length and the specimens were machined to have a uniform rectangular cross-section. Flexural stress waves in cortical bone were generated by impacting transversely 4.8 mm diameter spherical projectiles, fired from an air gun with the appropriate velocities. Stress waves were detected at two stations (positions) on the beam specimens by means of foil strain gages. These gages were suitably connected with a digital storage oscilloscope to detect the flexural stress waves produced by the lateral impact. Force history was recorded also on a storage oscilloscope by means of a sandwiched quartz crystal arrangement, of high frequency response, placed at the impact point of the specimen. A comparison was made between the corresponding analytical results and experimental data. Significant agreement was observed between them, as shown in the figures of this article.