Some may interpret the vertebral column or the spinal column as a single entity but in reality, the vertebral column is composed of 26 individual vertebrae. Five bones fuse together to form the sacrum and four bones fuse to form the coccyx.Credit: http://commons.wikimedia.org/wiki/File:Colonne_vertebrale.png
The Vertebral Column
The vertebral column is arranged in cervical, thoracic and lumbar regions. Each regions has a remarkable consistent number of bones; the cervical region has 7 mobile vertebrae that supports the neck and the head. It is normal for the cervical region to be curved or what medical professionals refer to as cervical lordosis which is attributed to the development of postural reflexes early in life. The thoracic region has 12 vertebrae and gives additional support to the head and the neck. Furthermore, the thoracic region also supports the thorax and meets with the ribs bilaterally. It is also normal for the thoracic spine to be slightly curved or congenitally curved which is also referred to as thoracic kyphosis. The lumbar region is composed of 5 vertebrae that gives support to the torso, upper body and lower back. When a human being begins to walk, this region becomes slightly curved or what is also known as lumbar lordosis.
The keystone of weight bearing arch is the sacrum which includes the hip bone. The number of fused bone that forms the coccyx is variable but the sacral/coccygeal curve is congenital. Between the variable 1-5 vertebrae that fuse together to form the coccyx, the first vertebrae may be movable.
The curvatures of the specific regions may be exaggeratedly affected by posture, obesity, activity, pregnancy, disease or trauma. Depending on where the exaggeration happens, the condition is given the same name with the specific region. In addition to the possibility of having exaggerated lordosis or kyphosis, there also a third exaggeration, often disabling called scoliosis or the lateral curvature of the vertebrae.Credit: http://www.pt.ntu.edu.tw/hmchai/Kines04/KINspine/Spine.htm
A motion segment is the basic movable unit of the back. Each pair of individual, unfused vertebrae consist this motion segment. Each pair of vertebrae in a motion segment, except C1 – C2 is attached by three joints, a partly movable intervertebral disc and a pair of gliding synovial facet. The facet joints and the intervertebral disc allow for movement in extension, flexion, rotation and side bending. To prevent the bones from falling apart, the ligaments envelopes the facet joints and secures together the bones. A canal exists in the middle of the vertebrae that allow the spinal cord and its coverings, nerve roots and vessels to pass through. For every pair of vertebral pedicles, a passageway exists that transmits spinal nerves and their coverings and some vessels that belong to the spinal cord. This passageway is called the intervertebral foramen.Credit: http://www.spineuniverse.com/anatomy/intervertebral-discs
The intervertebral discs serve as the spines protector. It can perform various actions like a shock absorber and allows for movement to be possible. The disc consists of the annulus fibrosus attached to the vertebral bodies and the central nucleus pulposus. The annulus fibrosus is a collection of collagenous fibers integrated to the cartilage cells. The nucleus pulposus is a collection of degenerated collagen and water. As the body ages, the water is consumed and the disc reduce in size, resulting in reduction of our height.Credit: http://biomechanism.com/exercise-produces-positive-effects-on-the-intervertebral-discs/
The vertebral column serves one very special purpose of protecting the spinal cord that is the bridge of the brain to the other parts of the body. Significant damage done to the vertebral column will make a huge impact in our way of living. Being prepared not just physically but also with enough knowledge can avert serious injury and debilitating ailments.