OBJECTIVE To investigate the effects of posterior implant rigidity on spinal kinematics at adjacent levels by utilizing a cadaveric spine model with simulated physiological loading. METHODS Five human lumbar spinal specimens (L3 to S1) were obtained and checked for abnormalities. The fresh specimens were stripped of muscle tissue, with care taken to preserve the spinal ligaments and facet joi...

this paper investigates axial compression process of multi-layered tubes with circular cross-section under the axial loading in the quasi-static condition using experimental method. some specimens are prepared in seven different groups, namely; empty carbon/epoxy composite tubes, solid carbon/epoxy composite rods, empty copper tubes, composite tubes with silicon sealant filler, concentrically s...

Mechanical overloading of the spine is associated with low back pain and intervertebral disc (IVD) degeneration. How excessive loading elicits degenerative changes in the IVD is poorly understood. Comprehensive knowledge of the interaction between mechanical loading, cell responses and changes in the extracellular matrix of the disc is needed in order to successfully intervene in this process. ...

BACKGROUND Although numerous suture-button fixation techniques for acromioclavicular (AC) joint reconstruction have been validated with biomechanical testing in the superior direction, clinical reports continue to demonstrate high rates of construct slippage and breakage. PURPOSE To compare the stability of a novel closed-loop double Endobutton construct with a commercially available cortical...

determination of volume change of unsaturated soils during loading and suction change is one of the most important difficulties in testing unsaturated specimens. it is revealed from literature review that various attempts have been made to invent an apparatus that can be used in testing on unsaturated soil specimens, simply and accurately. in this research, details of design and manufacture of ...

Three-dimensional L4-L5 finite element (FE) models of three disc heights (9.5mm, 11.5mm, and 13.5mm) and three disc wedge angles (5o, 8 o, and 10 o) were developed to investigate their effect on L4-L5 lumbar motion segment under pure axial compressive loading. The FE predictions indicated that the axial disc displacement and the posterior disc bulge increased greatly with an increase in the ave...