BACKGROUND One of the greatest challenges in the development of a nucleus prosthesis is to minimize the risk of implant expulsion. At the same time, the physiological flexibility, compressive behavior, and height of the disc should be restored. In this biomechanical in vitro study we investigated the ability of a new nucleus prosthesis made of knitted titanium filaments to meet these challenges...

Band clamps with a flat bottomed V-section are used to connect a pair of circular flanges to provide a joint with significant axial strength. Despite the wide application of Vband clamps, their behaviour is not fully understood and the ultimate axial strength is currently only available from physical testing. This physical testing has indicated that the ultimate strength is determined by two di...

This paper derives conditions for localized deformation for a transversely isotropic constitutive relation intended to model the response of geological materials in the axisymmetric compression test. The analysis considers the possibility of shear bands, with dilation or compaction, and pure compaction bands. The latter are planar zones of localized pure compressive deformation (without shear) ...

Human musculature is an important structure for appearance and deformation of body surface. In this paper, we propose a new method of muscle modeling based on both anatomical and real-time consideration. Furthermore, we introduce our muscle modeling system. In the system muscle can be constructed and edited easily through appointing some radial and transverse cross-section control parameters. D...

In this paper, crashworthiness characteristics of conical steel tubes stiffened by annular rings and rigid polyurethane foam are investigated. For this purpose, wide circumferential rings are created from the outer surface of the conical tube at some determined areas along tube length. In fact, this method divides a long conical tube into several tubes of shorter length. When this structure is ...

This paper describes triaxial compression tests conducted to determine the effect of fiber inclusion on stiffness and deformation characteristics of sand-gravel mixtures. Tested soil was a mixture of Babolsar sand from the shores of the Caspian Sea and Karaj River gravel. Portland cement was used as the cementing agent and fibers 12mm in length and 0.023mm in diameter at 0%, 0.5% and 1.0% were ...

In the hot compression test friction has a detrimental influence on the flow stress through the process and therefore, correcting the deformation curve for real behavior is very important for both researchers and engineers. In this study, a series of compression tests were simulated using Abaqus software. In this study, it has been employed the Taguchi method to design experiments by the factor...

STUDY DESIGN Biomechanics of human intervertebral discs before and after nucleotomy. OBJECTIVE To noninvasively quantify the effect of nucleotomy on internal strains under axial compression in flexion, neutral, and extension positions, and to determine whether the change in strains depended on degeneration. SUMMARY OF BACKGROUND DATA Herniation and nucleotomy may accelerate the progression ...