Causes and Diagnoses

Causes and Diagnoses of a Herniated Disk

A herniated disk is caused by a change in the structure of the normal disk, often due to a strain or injury. Most of the time, it occurs as a result of aging and age-related degeneration within the disk. Occasionally, severe trauma can cause a normal disk to herniate. Trauma may also cause an already herniated disk to worsen.


Your physician may use a variety of procedures to diagnose a herniated disk. In addition to a complete medical history and physical examination, you physician may use:

  • X-ray: Uses invisible electromagnetic energy beams to produce images of internal tissues, bones and organs onto film
  • Magnetic resonance imaging (MRI): Uses a combination of large magnets, radiofrequencies and a computer to produce detailed images of organs and structures within the body
  • Myelogram: Uses dye injected into the spinal canal to make the structure clearly visible on X-rays
  • Computed tomography scan (CT or CAT scan): Uses a combination of X-rays and computer technology to produce horizontal or axial images (often called slices) of the body
  • Electromyography (EMG) and Nerve Conduction Study: Measures electrical impulses along the nerves and muscle tissue to determine the extent of nerve damage