Degeneration of the intervertebral disc is a process that is fundamental to the development of degenerative disorders of the spine including intervertebral disc herniation, spinal stenosis, degenerative spondylolisthesis and discogenic back pain. These pathologies account for the vast majority of disability and operative care for spinal disorders. Degeneration of the intervertebral disc is a physiologic process, and disc degeneration is identifiable in the aging spine of patients with and without symptomatic back pain. The presence or absence of pain from a degenerated disc or spinal motion segment is of primary importance to the clinician who is treating a patient with symptomatic back pain. Pathologic disc degeneration is symptomatic or painful, while physiologic disc degeneration can exist with retention of the structural stability of the spine, preservation for neural function, and the absence of pain. One goal of our basic science research is to identify radiographic and molecular differences between pathologic and physiologic disc degeneration.
The development of alternative strategies for treating degenerated discs that restore disc structure and function is a contemporary challenge in the field of bioengineering, particularly in light of new minimally-invasive surgical techniques that efficiently access the intervertebral disc space. Another goal of our research is to develop biologic repair strategies that increase disc cellularity and matrix synthesis. The introduction of cells capable of producing normal extracellular matrix, in an environment of high pressure, low oxygen content and low pH is critical to the biological regeneration of the degenerated disc. Ongoing research includes study of mesenchymal stem cells (MSCs) and embryonic chondrocytes injected into the degenerated disc, and identification of patterns of differentiation of cells, and regeneration of the biochemistry and biomechanics of the intervertebral disc.