Dynamic stiffness and damping of human intervertebral disc using axial oscillatory displacement under a free mass system

Damping Properties of the Nucleus Pulposus

“…The NP samples were weighed and kept frozen at −18°C within 12 h of slaughter. Twelve hours prior to testing, the NP samples were placed into a hydrogel encapsulation device (HED) and let to swell in a phosphate buffered saline (PBS) solution in the refrigerator at 4°C (Izambert et al, 2003). The encapsulation device is composed of a medical grade 40 μm pore size sintered steel filter, a nonporous rigid disc, and a 100 μm thin polydimethylsiloxane (Sylgard 184, Dow Corning, USA) elastomer deformable membrane (Fig.…”

Controlling the magnetorheological suspension of a vehicle seat including the biomechanics of the driver

“…Discussion on the validity of these values has been presented on the example of mechanical properties (stiffness and damping) of lumbar spine disc. Izambert et al [10] conducted studies to analyze the dynamic response of the human intervertebral disc to vibration in a physiologically relevant frequency spectrum. Each sample was subjected to a preloading followed by dynamic compression (from 5 to 30 Hz) by using an experimental set-up comprising a free weight loading from above and a driving oscillatory displacement from below (closest to the in vivo loading).…”

“…From an observation of the spinal motion in fore-and-aft directions, Sandover and Dupuis [9] hypothesized that the principal resonance found at 4 Hz is related to bending motion of the lumbar spine. Izambert et al [10] conducted studies in which the aim was to analyse the dynamic response of the human intervertebral disc to vibrations. The mean resonant frequency was found at 8.7 Hz.…”

A Design of Experiments for Statistically Predicting Risk of Adverse Health Effects on Drivers Exposed to Vertical Vibrations

“…For the dynamic analysis of the lumbar spine, a distributed mass of ~55% of the total body mass was applied to the upper face of the rachis [20] to model the upper body. The mechanical properties of the various elements (cortical shell, cancellous bone, posterior elements and cartilaginous endplates, intervertebral disc) forming the vertebral body were taken from literature [21].…”

“…The stress responses were computed by considering viscous ξ = 10, 20, 30% as determined by Kasra, Shirazi-Adl and Drouin [21] and Izambert, Mitton, Thourot, et al [20]. · Three levels of body weight were chosen (light, medium, heavy).…”