The intervertebral disc consists of a soft, gelatinous core, which is enclosed by a collagenous fiber ring. The main function of the intervertebral disc is to distribute the forces that occur as a buffer and to ensure mobility between the individual vertebrae.

In the case of a herniated disc (disc herniation), the gelatinous core protrudes from the fiber ring. If the gelatinous core presses on a nerve or the spinal cord, pain, numbness, and paralysis in the extremities can occur. Often, disc protrusion occurs before the herniated disc. In this case, the fiber ring is still intact, but the gelatinous core is already bulging into the vertebral canal. In this case too, the protrusion can press on a nerve or the spinal cord.

In about 90% of cases, the intervertebral discs in the lumbar region are affected. The remaining 10% occur in the cervical region. In very rare cases, intervertebral discs of the thoracic spine can also be affected.

Risk factors for a herniated disc include obesity, poor posture, sedentary lifestyle, and lack of exercise. Inactivity leads to a nutrient deficiency in the intervertebral discs due to poorly perfused tissue, which makes them brittle. Brittle intervertebral discs significantly increase the risk of suffering a herniated disc.