Herniated disc facts
- The discs are pads that serve as "cushions" between the vertebral bodies, which minimize the impact of movement on the spinal column.
- Each disc is designed like a jelly donut with a central softer component (nucleus pulposus).
- Abnormal rupture of the central portion of the disc is referred to as a disc herniation.
- The most common location for a herniated disc to occur is in the disc at the level between the fourth and fifth lumbar vertebrae in the low back.
- If the disc herniation is large enough, the disc tissue can press on the adjacent spinal nerves that exit the spine at the level of the disc herniation.
- The physical examination, imaging tests, and electrical tests can aid in the diagnosis of a herniated disc.
- Depending on the severity of symptoms, treatments for a herniated disc include physical therapy, muscle-relaxant medications, pain medication, anti-inflammation medications, local injection of cortisone (epidural injections), and surgical operations.
How are the spine and its discs designed?
The vertebrae are the bony building blocks of the spine. Between each of the largest parts (bodies) of the vertebrae are the discs. Ligaments are situated around the spine and discs. The spine has seven vertebrae in the neck (cervical vertebrae), 12 vertebrae in the mid-back (thoracic vertebrae), and five vertebrae in the low back (lumbar vertebrae). In addition, in the mid-buttock, beneath the fifth lumbar vertebra, is the sacrum, followed by the tailbone (coccyx).
The bony spine is designed so that vertebrae "stacked" together can provide a movable support structure while also protecting the spinal cord (nervous tissue that extends down the spinal column from the brain) from injury. Each vertebra has a spinous process, which is a bony prominence behind the spinal cord that shields the cord's nerve tissue. The vertebrae also have a strong bony "body" in front of the spinal cord to provide a platform suitable for weight-bearing.
The discs are pads that serve as "cushions" between the vertebral bodies that serve to minimize the impact of movement on the spinal column. Each disc is designed like a jelly donut with a central softer component (nucleus pulposus). Ligaments are strong fibrous soft tissues that firmly attach bones to bones. Ligaments attach each of the vertebrae and surround each of the discs. When ligaments are injured as the disc degenerates, localized pain in the area affected can result.
What is a herniated disc?
As described above, each disc of the spine is designed much like a jelly donut. As the disc degenerates from age or injury, the softer central portion can rupture (herniate) through the surrounding outer ring (annulus fibrosus). This abnormal rupture of the central portion of the disc is referred to as a disc herniation.
The most common location for a herniated disc to occur is in the disc at the level between the fourth and fifth lumber vertebrae in the low back. This area is constantly absorbing the impact of bearing the weight of the upper body. This is especially important when we are standing or sitting. The lower back is also critically involved in our body's movements throughout the day, as we twist the torso in rotating side to side and as we hinge the back in flexion and extension while bending or lifting.