Lumbar Disc Disease Causes

Lumbar disc disease is caused by normal degenerative changes that occur as a person ages. The lumbar spine is composed of motion segments. Each motion segment consists of two vertebral bodies, the intervertebral disc, and two facet joints. The intervertebral disc acts as the cushion, or "shock absorber," of the spine.

The intervertebral disc is made up mostly of water. This allows it to maintain its cushion-like properties. As people age, the intervertebral disc loses some of its water content. As this happens, the outer layers of the disc are more likely to develop cracks or tears. These can be a significant source of low back pain. This is the beginning of internal disc disruption.

When the outer layer of the disc cracks, the disc looses its normal water content. This reduces its ability to act as a cushion for the loads applied to the spine. Eventually, it leads to a collapse of the disc and degenerative changes in both the vertebral bodies and the facet joints of the spine. When this occurs, the condition is known as degenerative disc disease.

The final process in lumbar disc disease occurs when the degenerative changes lead to destruction of the ligamentous and other soft tissue restraints of the spine. This is known as segmental instability, which occurs when a loss of the normal structural stability of the spinal segment occurs.