Spinal discs may be affected by degenerative, infective and traumatic conditions.
‘Disc disease’ generally refers to degenerative changes affecting a disc or discs, which will result in a gradual change in the physical characteristics of the disc, and which may become clinically symptomatic in a number of ways.
Degenerative changes in discs can be predisposed to by an individuals’ genetic makeup; by repeated heavy loads applied to the disc; by smoking; and possibly by the prior occurrence of Scheuermann’s disease – a self limiting developmental disorder of childhood.
Discs have similar structures throughout the spine, a central nucleus, surrounded by a multilayered annulus, and constitute a unique joint, which is mobile in all directions, including compression.
Healthy discs are tremendously strong and robust, and in fact, it is more likely that an excessive force will fracture a vertebra, than damage a normal disc.
However, a disc that has undergone degenerative changes is much more vulnerable to external stressors, and may suffer annular tearing, nuclear herniation (disc protrusion), or internal disc disruption. These pathologies may be clinically evident as back pain, leg pain (Sciatica), or neurological symptoms (numbness,tingling, weakness or sphincter disturbance (altered control of bowel or bladder).
‘Disc disease’ is often associated with other degenerative changes in the spine, affecting the facet joints, the ligaments, and the vertebral endplates.
Surgical therapies for symptomatic disc disease have expanded significantly in the last 15 years, and now range from microdiscectomy to Total Disc Replacement.
Currently investigations are under way to determine whether strategies such as stem cell implantation may provide additional treatment options, in selected circumstances.