Bone quality. Elasticity and strength.

The aim of the article is to explain in more detail the biomechanical methods used in determining bone quality as well as to describe basic characteristic bone qualities resulting from the application of these methods. Mechanical properties of biomaterials are characterised by stress-strain curves, produced on the basis of testing the biomaterials by progressive tensile and compressive load. According to these curves, the bone counts among brittle materials. Stress-strain curves under tensile and compressive load for brittle materials comprise proportional limit, elastic limit, and breaking strength. Recognition of biomechanical characteristics of bone quality (proportional limit, elastic limit, breaking strength) helps physicians to understand the importance of measuring the new parameters in bone densitometry by DXA (dual energy X-ray absorptiometry) such as femoral strength index (FSI), and safety factor (SF) (Fig. 2, Ref. 10). Full text (Free, PDF) www.bmj.sk.