The Human Spine
The human spine is an amazing apparatus, providing both structural support to the spinal column itself, but also with enough build in flexibility to bend forwards and backwards, died to side, and twisting. The differences in the human spine compared to those of apes and other mammals, is what gives us our ability to stand and walk upright. When the spine is young and healthy, we are able to go about our jobs and daily life, happy and carefree (at least emotionally). When we get hurt or do to some type of event, or time, certain structures in the spine may begin to wear down, and we may begin to feel some level of pain. Before discussing this any further, let's look at the anatomy of the spine, and what makes it so amazing.
The Anatomy of the Spine
The human spine includes 24 vertebral bones that lie vertically adjacent to one another, with the fused sacrum and coccyx located at its base. The human spine is also known as the vertebral column. The 24 vertebrae are connected to one another, and separated by intervertebral discs. The Vertebral bones themselves are not flexible; it is the intervertebral discs that give our spine (backbone) our flexibility. The spine begins at the base of our skull, with the axis and atlas bones, and terminates in the pelvis, with the sacrum and the coccyx. The sacrum is composed of 5 fused vertebrae, and the coccyx is composed of 4 partially fused vertebrae. The coccyx is also known as the tailbone.
The spine is designated with three sections: the cervical spine, thoracic spine and the lumbar spine. When a doctor or patient describes upper back pain (cervical spine), middle back pain (thoracic spine), or lower back pain (lumbar spine), the location of the pain often (but not always) corresponds to the section of the vertebral column that has been strained of damaged.
As stated above, the spinal vertebrae are separated by intervertebral discs. The discs are composed of cartilage and collagen fibers. These discs provide padding and shock absorption for the bones above and below them. Each pair of vertebrae creates a movable unit.
The Spinal Cord
The Vertebral column has serves us several functions, including allowing for movement, but its primary purpose is to house and protect the spinal cord itself. The spinal cord is an extension of our brain, and it gives us most of our senses and the ability to feel and move. The spinal cord runs within the vertebral canal formed by the back parts of the vertebrae. Thirty one pairs of nerves branch out from the spinal canal, through openings in the vertebrae, and to every muscle, bone, and tissue of our body.
Aging and Degeneration
First, let me state now that there are a high percentage of people with degenerative changes to their back that are highly functioning, and feel hardly any pain at all in their backs. That being said, degenerative changes to the discs that separate the vertebral bones are a leading cause of back pain. Lack of a good diet, aging, accidents, and muscular imbalances can cause excessive compression and thinning of the intervertebral discs. Eventually, that cushion that protects the spinal cord and the openings for the nerve roots to exit the spine become worn down, making the bones and openings vulnerable. This results in pressure on the nerves and the vertebral bones themselves.