MSD Examples: Low Back Disorders

Let's take a look at how the spine works to further understand how a MSD develops.

Vertebrae are the bones of the spine. Their function is to provide support and to protect the spinal cord. Between each vertebrae is a disc. The disc is actually a large, round ligament that connects the vertebrae together. The disc generally acts like a shock absorber.

The disc allows movement of the spine and helps transmit forces between vertebrae. As we use our backs each day, the disc is subjected to different types of stress. Repeated twisting, bending and lifting place perhaps the greatest stress on the spine, especially the disc. Bending over compresses the disc on one side, and may cause it to bulge. If the pressure is great enough, the disc may be damaged.

Over time, with repeated twisting, bending and lifting, the disc continues to be damaged as the tears become larger. Eventually, the damage becomes so severe a herniated disc occurs. In this injury, a tear in the disc allows material from the center of the disc to move into the spinal canal. If a spinal nerve is compressed by the disc material, there can be pain, numbness, and weakness along the path of the nerve.

Other examples of MSDs include trigger finger, carpal tunnel syndrome, and tennis elbow.