A critical review of the biomechanical stress analysis of the human femur.

The objective of this paper is to present a critical review of the mechanical behaviour of the human femur with particular emphasis on the determination of the internal stress distribution under the action of a variety of forces resulting from daily living activities. For attaining such a goal, knowledge of the applied forces in combination with the internal structure and the mechanical properties of the material of the femur is needed. The whole work is divided into four parts. In the first two parts a brief description of the structure and the mechanical properties of the cortical and cancellous bones of the femur determined from the tension, compression, shear, bending, torsion and impact tests takes place. The third part deals with the analysis of the joint and muscle forces acting on the femur. In the fourth part the mathematical and experimental methods for the determination of the stress distribution in the femur are presented in detail. The mathematical methods include use of the beam theory and finite elements, while the experimental methods incorporate the brittle and photoelastic coatings, the strain gauges and the two- and three-dimensional photoelasticity. Finally, an analysis of the strength characteristics of the femur from the point of view of fracture mechanics is undertaken.