Knowledge of trabecular bone behaviour under loading is very important for bone quality assessment. For numerical modelling of deformation behaviour of trabecular tissue it is necessary to establish a material model for single trabeculae. For visco-elasto-plastic material model used in this study have to determine eight material constants. Two elastic constants were obtained directly from nanoindentation test by Oliver-Pharr method. Remaining material constants were identified from a Finite Element (FE) simulation of nanoindentation test.

Annulus fibrosus as important element of structure of intervertebral disc play fundamental role in mechanical function of spine. Lamellar annulus fibrosus wall mainly consist of collagen fibers, water and proteoglycans. Arrangement of the fibrous matrix in intervertebral disc decide to nonlinear and strongly anisotropic tensile behaviour of the anulus fibrosus.
The presented study, provide information about influence number of lamellar, structural organization and connection vertebral bone with annulus fibrosus at mechanical properties.

Recent experimental and numerical studies have uncovered a fascinating pattern switching mechanism in 2D cellular structures under uniaxial compression. A square lattice of initially circular voids transforms into an array of mutually orthogonal ellipses as a result of a buckling instability triggered at a critical stress value. This reversible, repeatable phenomenon occurs globally throughout the sample and has been observed at the sub-micron level. This has led to the manufacture of tunable optical devices which utilise this geometric switching to alter photonic band gaps in periodic structures. The switch also causes a counter-intuitive auxetic effect.
Traditional studies of 2D cellular structures focus on the role of void size relative to the lattice on the response of these structures to compression. Here, we present the results of experiments which probe the influence of this parameter on 2D cellular structures possessing circular voids. These findings are compared with a simple spring-link model which uses potential energy minimization techniques to predict the collapse of the structure, and hence the onset of pattern switching, as a result of uni-axial compression.

Strain gauges are applied in a wide industrial range. Sometimes, their application can be very difficult or even impossible due to a lack of space or the requirement of an electronic connection with a processing unit. To avoid these problems, the SAW Components Dresden GmbH has developed a new sensor system for strain measurements. It is capable to transmit the measured signal directly from the sensor to the processing unit without any need of wires. In comparison to the strain gauge technology, the deformation on the components surface is not determined by a change of the sensors electrical resistance. Instead the SAW device measurement principle is based on the propagation of surface acoustic waves between two interdigital electrodes. The resonance frequency of the standing wave can be determined using an interdigital transducer. This resonance frequency is directly related to the tension of the sensor and decreases with increasing strain. The coupling factor between the modification of the resonance frequency and the tension of the component, the sensor is mounted to, can be described by the sensitivity, similar to the gauge factor of strain gauges.
The sensitivity of the SAW sensors is mainly affected by the transmission of strain in the intermediate layer between component and substrate as well as the strain transmission of the piezoelectric crystal itself.

The femoral bone is positioned between the hip joint and the knee joint, the upper extrimity taking on the bodies weight that is transmitted by the vertebral column to the pelvis.
The femoral bone fractures occur in the femoral neck region. The paper wants to show the state of stresses and the displacements that take place during the compression load in the femoral neck area – plane modelling.
Were approached three cases: 1) the femoral neck is not sectioned; 2) in the fractured area two screws are introduced, both having equal diameters; 3) the reconstruction is achieved with 3 screws of different diameters.
The study uses finite element method (RDM) and Digital Correlation System (DIC).