Synonyms in a broader sense
Discography, spondylodiscitis, spondylitis, discitis, intervertebral disc inflammation, vertebral body inflammation.
Definition
A discopathy describes the clinical picture of a disc causing back pain as part of its aging process. Pain is transmitted from the inside of the disc through the ingrowth of pain transmitting nerve fibers into the disc tissue. In a healthy state, they are otherwise not nerve fibers in the core of a disc.
Discopathy most often occurs in the area of the lumbar spine. A herniated disc also belongs to discopathies in a broader sense. However, the orthopedist working in the clinic distinguishes these clinical pictures.
The indication (advertisement) for the discography is made in the context of a back pain cause to be clarified. The patient’s medical history (anamnesis) can already provide indications for disc-related back pain. A characteristic feature of back pain caused by a disc is that patients often report being driven out of bed in the morning by their back pain.
Long lying aggravated thus the complaints. By getting up and moving the complaints improve at first. If the back is overstrained, however, the pain increases again.
This description of symptoms is only intended as a guide. The actual complaints of the patients are individually different. Certainly the presence of concomitant diseases, such as wear and tear of the small vertebral joints (facet syndrome) plays an important role, since the signs (symptoms) of facet syndrome can differ greatly from the symptoms of discopathy.
A further indication of a diseased disc is provided by magnetic resonance imaging of the spine (MRI). Here, the aging process of an intervertebral disc can be traced directly. Discs suspected of having discopathy appear black in the T2 weighting (black disc) in the MRI, i.e. they no longer have a nucleus of fluid (intervertebral disc), which is bright in a healthy intervertebral disc on the usually prepared MRI images.
The loss of water in an intervertebral disc is an indication of its aging process. Since the disc wear itself does not necessarily cause back pain, in some cases further examination by discography is necessary. A discography is performed under stationary conditions in the operating room.
It is a minor surgical procedure. The patient is informed the day before about the surgical procedure and the general and specific complications by the doctor and must give written consent to the procedure. It is important to clarify any contrast agent allergies in the patient’s medical history, since the use of X-ray contrast agent, if allergies are present, can lead to severe allergic reactions, up to and including allergic shock (circulatory arrest).
Anesthesia is neither necessary nor desired. In the operating room, the patient is positioned on his or her stomach, the operating field is disinfected and covered with sterile cloths. First of all, the suspicious intervertebral disc is searched for with a mobile X-ray unit (image converter).
After identification of the intervertebral disc, the puncture channel for the injection of contrast medium is anaesthetized with a local anaesthetic. Then the disc space is accessed with a thin needle (cannula). The puncture channel for puncture of the intervertebral discs at the lumbar spine runs diagonally from the posterior iliac crest.
This is experienced as unpleasant by many patients despite local anesthesia. In this case, the anaesthetist can administer a painkiller through the vein. The placement of the needle in the intervertebral disc space is again under X-ray control.
Then the X-ray contrast medium is injected into the intervertebral disc. A problematic aspect of discography is the subjectivity of pain differentiation by the patient. The physician cannot objectively verify the patient’s statement and must rely on the patient’s judgement.
For this reason, some physicians doubt the significance of this procedure.
- By injecting the contrast medium, the disc structure becomes visible on the X-ray image. Without contrast medium, the intervertebral discs are only shown on an X-ray as empty spaces between the adjacent vertebral bodies.
The distribution of the contrast medium allows conclusions to be drawn about the condition of the intervertebral disc. A loss of contrast medium from within the disc body indicates, for example, a fracture in the disc ring.
- Above all, however, the injection (injection) serves to secure the cause of back pain.The injection of the contrast medium leads to an increase in pressure in the intervertebral disc space, which leads to a provocation of pain in a diseased disc. The patient should feel exactly the pain known to him during the injection and articulate this to the doctor. If this is the case, one speaks of a positive distension test. If no pain is provoked, the distension test is negative and the cause of the back pain remains unexplained at first, or the back pain is not caused by this disc.
- Intervertebral disc space
- Discography needle
- Contrast medium imaging of the intervertebral disc L4/5
- Contrast medium leakage into the spinal canal (defective disc ring)
- Spinal canal
