Intervertebral discs

Discs that act as cushions between the vertebrae of the spinal column.

Intervertebral discs are flexible, fibrous structures located between the individual vertebrae in the spinal column. Each disc consists of a tough outer layer known as the annulus fibrosus and a gel-like center called the nucleus pulposus. These discs provide support and mobility to the spine, helping to absorb shock and allowing for slight movement between the vertebrae.

Terminologia Anatomica

discus intervertebralis

System

Musculoskeletal system

Function

The primary role of intervertebral discs is to provide cushioning and support for the spinal column. Acting as shock absorbers, they help to alleviate pressure during daily activities, such as walking or lifting. This cushioning effect is vital in preventing wear and tear on the spinal vertebrae, as it allows for a greater range of movement, including flexion, extension, and twisting motions. Additionally, the discs facilitate communication between the vertebrae, contributing to overall spinal stability and alignment. Each disc is essential for maintaining proper posture and flexibility in the spine, which is crucial for tasks as simple as sitting or standing. When discs become damaged or degenerate, they can lead to various spinal issues, such as herniation or degenerative disc disease, affecting mobility and causing pain.

Location

Intervertebral discs are located throughout the vertebral column, positioned between each pair of adjacent vertebrae. There are a total of 23 intervertebral discs in the human spine, situated in the cervical, thoracic, and lumbar regions. The cervical (neck) region contains seven discs, while the thoracic (mid-back) region has twelve. The lumbar (lower back) region is composed of five discs, with the most prominent being the lumbar discs, as they are subject to the greatest load and movement. The sacral area has fused vertebrae that do not contain intervertebral discs, marking the end of the spinal column.

Did You Know?

Intervertebral discs are made up of about 80% water, which decreases with age, leading to reduced disc height and flexibility.
The nucleus pulposus can regenerate under certain conditions, which is a promising area of research for treating disc injuries.
Disc herniation is more common in the lower back and can cause pain and numbness in the legs due to pressure on spinal nerves.