The document provides an overview of the structure and function of the spine. It discusses the history of chiropractics, the natural curves of the spine, the muscle groups that support it, the individual bones (vertebrae) that make up the spinal column, the spinal cord and nerves, and how damage to the spine or cord can impact movement and sensation. Maintaining good posture through exercise is important for keeping the spine healthy.

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Michael Hill
Ms. Bennett
British Lit
Overview
The spine provides the main support for the human body by, allowing the person to stand up
straight and bend and twist while protecting the spinal cord from injury. Strong muscles and
bones, flexible tendons and ligaments, and sensitive nerves contribute to a healthy spine. A
healthy spine is flexible, strong and allows a good range of motion. If any of the spinal structures
were affected by strain, injury, or disease it can cause a significant amount of pain.
History of chiropractics
L;The history of chiropractics dates back to 1895 when Daniel David palmer did an adjustment
on a man‟s neck and restored the man‟s hearing. A few years later in 1897, Dr. Palmer founded
the school of Chiropractic located in Davenport, Iowa. This school still trains chiropractic
doctors to this day. Throughout the years the profession of chiropractic care has gained much
respect.
Spinal Curves
When born a baby‟s spine is „C‟ shaped. The adult spine naturally curves to form an „S‟ shape.
Although in this S posture, the spine is constantly being pulled forward by body weight. The
spine‟s curves work as if they were like a coiled spring to absorb shock, allow total range of
motion, and maintain balance. Natural curves of the spine are kept by correct posture and the
muscles. To maintain good posture it involves the training of the body to stand, walk, sit, and lie
in a way that puts the least amount of strain on the spine. When the spine abnormally curves
from side to side it is called scoliosis. Scoliosis can often limit physical activities and also put
pressure on the heart and lungs. An abnormal forward curve of the spine is called sway back, and
an abnormal curve of the thoracic spine is called hunchback. A mild curvature of the spine that is
less than 20 degrees is usually not a concern. However, moderate curves between 25 to 45
degrees and major curves higher than 45 degrees are treated seriously.
Muscles
There are two main muscle groups that affect the spine called extensors and flexors. The
extensor muscles allow the person to lift objects and stand up; also they are attached to the back
and spine. The flexor muscles are in the front of the body along with the abdominal muscles.
These muscle groups allow a person the movement of flexion, or to bend forward, and important
in controlling the arch in the lower back during activities such as lifting. Something as minor as a

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large belly or lack of muscle tone can pull the body out of alignment. The back muscles stabilize
the spine and any misalignment will put an incredible amount of stress on the spine.
Vertebrae
There are 33 individual bones that are interlocked with one another, forming the spinal column.
These are known as the vertebrae‟s. There are only 24 top bones that are moveable. The sacrum
and coccyx are immobile but still serve a purpose. The vertebrae are divided into the following
regions: 7 cervical, 12 thoracic, 5 lumbar, 5 sacral, and 4 coccygeal. Each vertebrae region has
special features that help them carry out their main functions. In the spine, the cervical regions
main function is to support the weight of the head. There are 7 cervical vertebrae, and they are
numbered C1 to C7. The cervical region of the spine has the greatest range of motion due to two
specialized vertebrae that connect to the skull. The first vertebra C1 is a joint that allows for the
nodding “yes” motion of the head. The second vertebrae C2 is a joint that allows for the “no”
motion of the head. The main function of the Thoracic spine is to protect the chest organs by
providing an attachment for the rib cage. There are 12 thoracic vertebrae numbered T1 to T2.
The lumbar regions of the spine are useful to bear the weight of the body. All five lumbar
vertebrae are numbered L1 to L5. These lumbar vertebrae are much larger in size for their
specific body supporting function. The main function of the sacarum is to provide protection for
the pelvic organs and provide attachment for the hip bone. There are five sacral vertebrae and
together they for a ring called the pelvic girdle. The coccyx region or tail bone doesn‟t really
have a function; it is more of a remaining tail from our primate ancestors.
Spinal cord
The spinal cord is about 18 inches long with the thickness of a thumb. The spine runs within the
spinal canal from the brainstem to the 1st lumbar vertebrae. At the very end of the spinal cord,
there are cord fibers that separate into the cauda equine (a bundle of spinal cords) and continue
down to the tailbone. The brain sends messages through the spinal cord allowing movement of
the body. The limbs of the body send the so called sensory messages to the brain through the
spinal cord and these messages allow the human body to experience touch and feel. When the
spinal cord reacts without the sending of messages to the brain, as an immediate protection from
harm, it is called reflex. The nerve cells that are included in the makeup of the spinal cord are
called upper motor neurons. The nerves that branch off of the spinal cord and down the back and
neck are called the lower motor neutrons. These nerves exit out of the vertebrae and distribute all
throughout the body. When the spinal cord is damaged, depending on the severity of the injury,
the spinal cord could possibly lose few functions to loss of full function of the body. For
example, an injury to the neck area could possibly result in the loss of motor skills in the arms
and legs.
Spinal nerves

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The spinal nerves are constantly carrying messages to and from the spinal cord and the body.
There are 31 pairs of spinal nerves that branch off of the spinal cord. Out of all 31 pairs of spinal
nerves, each spinal nerve has two roots. The first root is the ventral (front) root, and this root
carries impulses from the brain. The second root is the dorsal (back) root, and this root carries
impulses to the brain. The two roots are connected together to form the spinal nerve, which is
located all down the spinal canal. These nerves are connected all throughout the body and supply
us with touch, feeling, and sensation.