MRT of the lumbar vertebrae
The 5 lumbar vertebrae form the lumbar spine, i.e. the lower part of the spine between the thoracic spine and the sacrum. For classification purposes, they are numbered L1 to L5, which allows them to be precisely assigned on imaging systems such as CT, MRI or X-ray. A lumbar vertebra consists of a vertebral body (corpus vertebrae) and a vertebral arch (arcus vertebrae).
From here, the transverse processes (Processus transversi) extend laterally and the spinous processes (Processus spinosi) extend to the rear. They serve the musculature as attachment points. Together with the vertebral body, the vertebral arch forms the vertebral hole (Foramen vertebrae), in which the spinal cord is normally located.
The vertebral holes of all vertebrae together form the spinal canal. However, the special feature of the lumbar spine is that from the first or second lumbar vertebrae onwards, the spinal cord no longer runs as a single strand, but only the spinal nerves hang down like individual thin threads (the so-called cauda equina). Like the spinal cord in the spinal canal, these are also surrounded by spinal cord skin, neural fluid, vessels and nerves. In addition to the vertebral hole, two vertebrae lying on top of each other form an intervertebral foramen (foramen intervertebrale) on each side, through which the spinal cord nerves (spinal nerves) pass. These and the spinal canal are relevant for understanding the herniated disc, which is described below.
MRI for a slipped disc
A herniated disc is a slowly or suddenly emerging bulge of the disc material into the so-called spinal canal, in which the spinal cord runs. This is the so-called nucleus pulposus, the gelatinous core of the intervertebral discs, which loses its elasticity with age due to water loss. Overloading the spine for years through work, competitive sports or pregnancy promotes wear and tear and can lead to a herniated disc.
A herniated disc not only enters the spinal canal at the back, but also at the back-side, where the nerve root emerges. Depending on the area of the body in which the patient’s movement, sensation and/or reflexes are disturbed, a presumption can be made during the physical examination as to which area of the spine the herniated disc is located. This protrusion can lead to paralysis, numbness or pain due to pressure on the spinal cord or nerve root.
Most often the lumbar spine is affected, which, if it is affected, causes mainly complaints in the genital region and the legs. In order to differentiate what the cause lies behind the complaints, MRI of the spinal column is best suited, which, unlike other imaging procedures, best depicts the intervertebral discs. With the addition of the contrast medium, it is possible to further differentiate between tumorous or inflammatory causes, and thus, by excluding the latter, a herniated disc can be specifically depicted.
Depending on the necessity and severity of the symptoms, the therapy can be conservative or surgical. The conservative therapy includes a relief of the spine, whereby strict bed rest is not necessary, medication for pain relief as well as specific physiotherapy. In the case of acute paralysis, however, relief of the nerves is necessary, so that the surgical route should be taken. You are afraid of suffering from a slipped disc? Do our self-test herniated disc:
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