MRI Techniques for Describing Alterations in Material Properties of Cartilage and Intervertebral Disc Tissue

The aim of this review is to present the different stages, from geometrical to mechanical data, in the development of sensitive and non-invasive MRI techniques for describing alterations in material properties of cartilage and intervertebral disc tissue with disease. The first section summarizes some MRI techniques used to quantify the geometrical changes in cartilage and intervertebral disc tissue that appears with diurnal activity, specific movements or loadings, or else with various diseases. The second section describes the MRI techniques used to evaluate the biochemical composition of cartilage and intervertebral disc tissue, mainly the glycosaminoglycans (GAGs) and water contents, and the collagen organization. The third section describes the MRI techniques used to quantify the mechanical and structural properties of bone tissue. The last section presents the new MRI techniques used to evaluate the mechanical properties of hydrated cartilage and intervertebral disc tissue. More studies highlighting the ability of MRI to describe the fluid phase behavior within the cartilage or intervertebral discs tissue should be perform. The long term goal would be to develop sensitive and non-invasive clinical techniques for the early detection of the changes in the mechanical properties of both solid and fluid phases that appear with degeneration.