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Introduction:- The spine works as the main support for the spinal cord and the nerve pathways that carry information from the arms, legs, and rest of the body, and carries signals from the brain to the body.
Your back is composed of 33 bones called vertebrae, 31 pairs of nerves, 40 muscles and numerous connecting tendons and ligaments running from the base of your skull to your tailbone. Between your vertebrae are fibrous, elastic cartilage called discs. These "shock absorbers" keep your spine flexible and cushion the hard vertebrae as you move.
Bony Anatomy
Cervical Spine
There are seven cervical bones or vertebrae. The cervical bones are designed to allow flexion, extension, bending, and turning of the head. They are smaller than the other vertebrae, which allows a greater amount of movement.
Each cervical vertebra consists of two parts, a body and a protective arch for the spinal cord called the neural arch. Fractures or injuries can occur to the body, lim pedicles, or processes. Each vertebra articulates with the one above it and the one below it.
Thoracic Spine
In the chest region the thoracic spine attaches to the ribs. There are 12 vertebrae in the thoracic region. The spinal canal in the thoracic region is relatively smaller than the cervical or lumbar areas. This makes the thoracic spinal cord at greater risk if there is a fracture.
The motion that occurs in the thoracic spine is mostly rotation. The ribs prevent bending to the side. A small amount of movement occurs in bending forward and backward.
Lumbosacral Spine
The lumbar vertebrae are large, wide, and thick. There are five vertebrae in the lumbar spine. The lowest lumbar vertebra, L5, articulates with the sacrum. The sacrum attaches to the pelvis. The main motions of the lumbar area are bending forward and extending backwards. Bending to the side also occurs....
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