Intervertebral discs

The length of the intervertebral disc is one quarter of the length of the entire spine. There are no discs between Atlant (C1), Axis (C2) and the tailbone. The intervertebral discs are in the form of fibrous cartilage, a convex pillow that acts as an absorbing system for the spine, which protects the vertebrae, brain, and other structures (including nerve structures). The capabilities of one intervertebral disc do not allow for full amplitude movement – at the same time, several intervertebral discs, by combining efforts, can provide full-fledged back movements.

The intervertebral discs consist of a fibrous ring and a pulpous nucleus. The fibrous ring consists of elastic collagen fibers that are connected to the intervertebral discs. The fibers in their mass are oriented at different angles. The fibrous ring covers the pulpous nucleus.

Despite the fact that both the fibrous ring and the pulp nucleus consist of water, collagen, proteoglycans (PG), the bulk of the liquid (water and PG) occupies the largest part of the pulp nucleus.

PG molecules have a very important function – they attract and retain water. The pulpous nucleus contains a hydrating gel, which creates resistance to compression. The amount of water in the core is constantly changing depending on human activity.

The percentage of water in the intervertebral discs decreases over time (if at birth it reaches 80-90%, then after 50 years – this figure is only 60-70%) – which is one of the reasons for the natural development of back diseases.