Spine Anatomy
The back is a complex part of your body. The spine which is part of your central nervous system controls your body’s functionality that is sent from your brain. Your spine is made up of 33 bones stacked on top of each other which is called vertebrae. In Between those vertebrae are intervertebral discs which keeps your bones from rubbing against one another.
Vertebrae
The 33 individual bones making up your spinal column are divided into several regions. Only the first 24 bones that make up your spine have the ability to move. Each section in your spine has a special function. The functions are listed below:
Cervical: The cervical portion of your spine is C1-C7 which is your neck. These vertebrae allow your neck to move from side to side and up and down. This portion of your spine has the ability to move the most.
Thoracic: Mid back portion of your spine that protects the heart and lungs. Thoracic is labeled as T1-T12. The range of motion in this portion of your spine is very limited and injuries to your thoracic spine is rare.
Lumbar: Lower back portion is an area where most people have back pain. The Lumbar portion of your back is labeled L1-L5. It supports your upper body and allows for you to twist.
Sacrum: Connects your spine to the hip. There are five vertebrae making this portion up.
Coccyx Region: Made up of four vertebrae
Intervertebral disc
Jelly like substance that keeps your vertebrae from rubbing against one another. There is an outer ring which is called and annulus and an inner ring which is called the nucleus. Annulus is the outside layer that is sturdier than the inside layer because it has a higher concentration of collagen fibers. The nucleus in your disc has more water which allows it to transmit stress/pressure from one vertebrae to another.
As we age, our discs become more brittle which causes degenerative disc disease. Over 60% of Americans will develop degenerative disc disease which is caused by the natural aging process. When you hear of old people shrinking it is due to degenerative disc disease.
Some injuries that cause back pain are due to the discs compressing and going out of place. Herniated discs and Bulging discs occur that impinge on the spinal cord or spinal nerves causing sharp pain which causes back pain.
Facet Joints
The Facet Joints allow your vertebrae to move, it also connects your vertebrae to one another. Every vertebrae has four facet joints.
Spinal Cord
Your spinal cord is 18 inches long and about 1 inch in thickness. It extends from your brain stem all the way down to your spine. This portion of your spine is essential for relaying messages from your brain to your entire body. It is responsible for your movements and senses. Damaging your spinal cord can result in serious injuries such as loss of motor skills and sensory functions. Herniated discs can also cause issues by impinging on your spinal cord which transmits pain signals to your brain.
The front of your spinal cord is responsible for transmitting movement from your brain to your body. The back of your spinal cord is responsible for relaying sensory information from your body. This is divided into two sections which is the anterior root and the posterior root.
Spinal Nerves
The main job of your spinal nerves are to carry messages from your spinal cord to your body. It is an essential messaging system. The front of your spinal cord is called the anterior root and the back of your spine is called your posterior root. Both of these sections make up your spinal nerves. There are 31 pairs of spinal nerves. Here are how many pairs of spinal nerves in the specific sections of your spine:
Cervical: 8 pairs
Thoracic: 12 pairs
Lumbar: 5 pairs
Sacral: 5 pairs
Coccygeal: 1 pair