Mechanics of hard tissues

The goal of this introduction to the mechanics of bone tissue has been to show the need for interdisciplinary approaches to understanding skeletal mechanics. In the first section, the experimental results were highlighted to demonstrate some of the complexities of bone tissue, including its structural complexity, its sensitivity to moisture, its inhomogeneity, its dependence upon loading rate, its viscoelastic response, its strength dependence upon loading type, and its response to repeated loading. In addition to complexity in mechanical behavior, some of the purely biological aspects of skeletal tissue were introduced with a focus upon the role of the bone cells in changing the material behavior and geometric structure of bone. These complex mechanical and biological behaviors were employed to motivate the theoretical descriptions that are used to quantify behavior,bone’s behavior, although only the simplest linear elastic behavior was included. A number of ideas about how to simulate the adaptive response of bone tissue was introduced, and the role of numerical simulations in the study of bone and implants and in the study of the adaptive response was highlighted. Despite the required brevity, this introduction has highlighted the need for a multidisciplinary approach to the study of skeletal mechanics that requires a team with competencies in clinical, mechanical, chemical, experimental, and numerical approaches. Future progress will be increasingly dependent upon collaboration, and hold the promise of prediction of bone responses, study of skeletal disease, and development and manipulation of therapeutic agents to repair, and to perhaps avoid, skeletal disease.