Simultaneous In Vitro Measurement of Intervertebral Disc Bulging and Pressure

Disc herniation and low back pain constitute widespread problems in modern society, although a direct relationship between both conditions has not been established. Proper quantification of intervertebral disc bulging is important for studies on pathogenesis and pathological conditions of disc related disease such as herniations. Intervertebral disc disorders are related to the mechanical failure of the annulus fibrosus [1] and annulus failure is caused by high tensile stresses produced by the high intervertebral disc pressure [2]. To the best of the authors’ knowledge, there has been no study on the simultaneous measurement of disc bulging and the disc pressure under physiological loading conditions. The objective of this study was to describe the radial displacement of the outer annulus wall under a variety of loading schemes. Moreover, this data could also be used to assist in the validation process for finite element models.