Lumbar disc behavior under static & vibratory loading & it’s implications on spinal movement

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The following Part of another my review…………

Lumbar disc herniations can be a direct mechanical consequence of prolonged sitting in static or vibration environments that challenges the stability of this region.

Static loading: A 1 hour exposure to static lumbar loading such as sitting cause significant changes in the mechanical properties of the lumbar intervertebral disc exhibited by a sudden, large flexion and/or lateral bend rotation response to an axially applied load. This further implies that a motion segment in the lumbar spine suddenly buckles and applies a tensile impact loading to the posterolateral region of the disc.

Vibratory loading (Driving a car, truck, tractor etc): A combined lateral bend, flexion, and axial rotation vibration loading could cause tracking tears proceeding from the nucleus through the posterolateral region of the annulus.

Mechanical impacts of static & vibratory loading on disc reveal that mechanism for disc herniation is mechanical change leading to instability of the motion segment.

Reference:
Wilder DG et al; J Spinal Disord. 1988;1(1):16-32.


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