One effect of aging and disc degeneration is that the nucleus pulposus begins to dehydrate and the concentration of proteoglycans in the matrix decreases, thus limiting the ability of the disc to absorb shock. This general shrinking of disc size is partially responsible for the common decrease in height as humans age. The anulus fibrosus also becomes weaker with age and has an increased risk of tearing. In addition, the cartilage endplates begin thinning, fissures begin to form, and there is sclerosis of the subchondral bone. Since the fissures are formed in the anulus fibrosus due to osteo-arthritic bones or degeneration in general, the inner nucleus pulposus can seep out and put pressure on any number of vertebral nerves. A herniated disc can cause mild to severe pain such as sciatica and treatment for herniated discs range from physical therapy to surgery. (see also: Intervertebral disc arthroplasty) Other degeneration of the vertebral column includes diffuse idiopathic skeletal hyperostosis (DISH) which is the calcification or ossification of the ligaments surrounding the vertebrae. This degeneration causes stiffness and sometimes even curvature in the lumbar and thoraco-lumbar spinal region. Burgeoning evidence suggests that long-term running may mitigate age-related degeneration within lumbar intervertebral discs

Scoliosis
While this may not cause pain in some people, in others it may cause chronic pain. Other spinal disorders can affect the morphology of intervertebral discs. For example, patients with scoliosis commonly have calcium deposits (ectopic calcification) in the cartilage endplate and sometimes in the disc itself.
An intervertebral disc (or intervertebral fibrocartilage) lies between adjacent vertebrae in the vertebral column. Each disc forms a fibrocartilaginous joint (a symphysis), to allow slight movement of the vertebrae, to act as a ligament to hold the vertebrae together, and to function as a shock absorber for the spine. Structure
Intervertebral discs consist of an outer fibrous ring, the anulus fibrosus disci intervertebralis, which surrounds an inner gel-like center, the nucleus pulposus. The anulus fibrosus consists of several layers (laminae) of fibrocartilage made up of both type I and type II collagen. Type I is concentrated toward the edge of the ring, where it provides greater strength. The stiff laminae can withstand compressive forces. The fibrous intervertebral disc contains the nucleus pulposus and this helps to distribute pressure evenly across the disc. This prevents the development of stress concentrations which could cause damage to the underlying vertebrae or to their endplates. The nucleus pulposus contains loose fibers suspended in a mucoprotein gel. The nucleus of the disc acts as a shock absorber, absorbing the impact of the bodys activities and keeping the two vertebrae separated. It is the remnant of the notochord.There is one disc between each pair of vertebrae, except for the first cervical segment, the atlas. The atlas is a ring around the roughly cone-shaped extension of the axis (second cervical segment). The axis acts as a post around which the atlas can rotate, allowing the neck to swivel.