Spinal discs and ligaments | Anatomy of the spine

Spinal discs and ligaments

An intervertebral disc (= intervertebral disk) represents the cartilaginous connection between two vertebral bodies. It consists of a connective tissue and cartilaginous outer ring, the so-called annulus fibrosus, and a soft inner gelatinous core, the nucleus pulposus.

  • Intervertebral disc (intervertebral disc) – Discus inter vertebralis
  • Gelatinous nucleus – nucleus pulposus
  • Fiber ring – Anulus fibrosus
  • Spinal nerve – N. spinalis
  • Spinal cord – Medula spinalis
  • Spinous process – Processus spinosus
  • Transverse process – Processus transversus
  • Superior articular process – superior articular process
  • Intervertebral hole – Foramen intervertebrale
  • Vertebral body – Corpus vertebrae
  • Anterior longitudinal ligament – Lig.

    longitudinal anterius

The intervertebral disc acts as a buffer, absorbing shocks and vibrations that affect the spine. In addition, it also allows the individual vertebrae to move better with each other. Not all vertebrae have such a buffer: The first and second cervical vertebrae form a special joint and therefore have a different structure.

The same applies to the sacrum and coccyx vertebrae, which merge with each other during development (see: sacrum and coccyx above). Due to the important tasks and functions attributed to the intervertebral disc, it is understandable that a special responsibility must be shown to it. This means: Damage to the spinal column must be avoided if possible.

This can be achieved, for example, through “back-friendly” behavior (“back school“). Beyond that, however, it is also of particular importance that the intervertebral disc as such is properly nourished. This “correct” nutrition has nothing to do with healthy food intake as such.

The mobility and elasticity of the intervertebral disc is achieved through regular fluid intake, which in turn can only be achieved through healthy and sufficient human movement.If the intervertebral disc is loaded and unloaded in adequate alternation, sufficient fluid absorption is usually ensured by “working into the disc”. To maintain the elasticity of the intervertebral disc, nothing is as important as movement. However, this degree of movement should be appropriate.

This means that even permanent movement with only slight breaks can have just as negative an effect as a chronic lack of movement. In both cases, the cartilaginous outer ring can become brittle and cracked. The inner gelatinous core is thus given the opportunity to emerge, so that under certain circumstances a herniated disc can develop.

In order to ensure that the spinal column is not only supported, but also has maximum mobility, strong ligaments must be in place that extend over the entire length of the spinal column. In addition, further ligaments are necessary, which will be presented in the course of this article. The back muscles also provide additional support for the entire ligament system.

Only the joint action and mutual support enables the well-known elastic and stabilizing function and structure of the spinal column and thus enables the numerous possibilities of movement in all directions, including possible rotational movements.

  • The anterior longitudinal ligament is responsible for stabilization between the abdominal cavity and the spine.
  • The posterior longitudinal ligament extends over the posterior vertebral body surfaces and lines the anterior spinal canal area.
  • The yellow band (= Ligamentum flavum) is located between the respective vertebral arches.
  • A belt system connects the transverse processes of the individual vertebrae with the intermediate transverse processes.
  • A band system (= inter-spinous process – bands) connects the spinous processes and thus the vertebral backs with each other.
  • In addition, a ligament extends over all spinous processes and supports the spine in the form of a posterior stabilization.

The intervertebral disc serves as a buffer between two vertebrae. It consists of an outer fibrous ring (annulus fibrosus) and an inner core of gelatinous mass (nucleus pulposus).

The nucleus serves the reversible water binding, i.e. it can – depending on the current load condition of the respective spinal segment – release (heavy load) or absorb (decreasing load) water, thus acting like a kind of water cushion or sponge. The intervertebral disc is therefore the shock absorber of the spine and thus exposed to enormous forces, which is reflected in the increasingly frequent disc protrusions or even prolapses of the disc that occur even in early years of today’s patients. In such a herniated disc, the outer fibrous ring becomes porous and cracked, so that parts of the nucleus emerge and partially slide down into the spinal canal, where they can irritate nerves running there (see below).