General information
The intervertebral discs connect the vertebral bodies of the spine with each other. They are located between the vertebral bodies in question and consist of fibrous cartilage. This is not a rigid but a flexible connection, which allows the spinal column the possible freedom of movement.
The human body has 23 intervertebral discs, which consist of a fibrous ring (Anulus fibrosus) and a soft gelatinous core (Nucleus pulposus). The intervertebral discs primarily buffer pressure loads on the spine caused by muscle tension. The longer the intervertebral discs are (mis)loaded or damaged, the higher the probability of the occurrence of herniated or protruding discs. But genetic factors, arthrosis and signs of wear and tear also play a role.
Definition
A disc protrusion is also called a disc protrusion or “incomplete disc prolapse” in medical terminology. One observes this event more and more often with increasing age. The size and nature of the disc protrusion differs from the so-called herniated disc (disc prolapse) and must be distinguished from it.
In a herniated disc, parts of the disc enter the spinal canal. The spinal canal is the bony canal in which the spinal cord lies. In contrast to the disc protrusion, the fibrous ring (Anulus fibrosus) of the disc tears partially or completely in the herniated disc.
With a herniated disc, the fibrous ring is only bulged outwards and in the worst case only very slightly torn. In general, there are also differences in imaging diagnostics. In magnetic resonance imaging during a disc protrusion (MRI for short), the vertical diameter of the affected disc is smaller or equal to the height of the disc. A disc protrusion can be painless. Depending on its location, however, it can also cause pain in the spinal canal, which may radiate into other parts of the body.
Symptoms of disc protrusion
A herniated disc can initially be symptom-free. Usually, however, it manifests itself in pain at the affected area of the spine. This pain can radiate to other parts of the body.
The localization then depends on which part of the spinal cord or which nerves are affected or compressed by the bulge. In the case of impairments in the lumbar region of the spinal column (lumbar spine), the pain may radiate into the legs, for example, whereas bulges further away from the head may radiate painfully into the arms. According to recent studies, however, the pain generally results from inflammatory reactions rather than nerve compression.
In rare cases, vegetative functions may also be impaired. These include stomach, intestinal and bladder problems. In addition, a disc protrusion can lead to movement restrictions and stiffening.
The lumbar spine is most frequently affected. This is exposed to a higher weight load than higher parts of the spine. The cervical spine is also affected more often.
The thoracic spine, however, is almost never affected. A disc protrusion can be completely painless, or it can be accompanied by severe pain. On the one hand, this depends on how quickly the bulge develops; for example, a disc bulge can be painless if it develops over several weeks and months.
The faster the disc bulges, the more nerve fibres are compressed. This causes severe pain and possibly even numbness or paralysis. These are described as deep-seated, dull and sometimes burning.
The location of the pain depends on the height of the disc protrusion. If the cervical spine is affected, pain occurs mainly in the neck and arms up to the fingers. If the thoracic or lumbar spine is affected, patients complain mainly of back pain and pain radiating into the legs. This is due to the fact that the trapped spinal nerves extend into the leg in the case of a lumbar spine bulge or into the arm in the case of a cervical spine bulge.
All articles in this series:
