The spine is one of the most
important parts of your body.
Without it, you could not keep
yourself upright or even stand up.
It gives your body structure and
support. It allows you to move
about freely and to bend with
flexibility. The spine is also
designed to protect your spinal
The spine of a newborn is Cshaped, with one curve
At About Six Months
As the infant lifts his or her head during
the first few months, the neck (cervical)
curve and its muscles develop
At About Nine Months
As the infant learns to crawl and stand,
the lower back (lumbar) curve and its
muscles develop. Strong back muscles
help give your child the strength and
balance to walk and run.
The spine has Three
major componenTs :
•the spinal column (i.e., bones and
•neural elements (i.e., the spinal
cord and nerve roots)
•supporting structures (e.g., muscles
a. The spinal column
The spinal column consists of individual bones called
vertebrae, the building blocks, which provide
support for the spine. These vertebrae are
connected in the front of the spine by
The spinal column consists of:
•seven cervical vertebrae (C1–C7) i.e. neck
•twelve thoracic vertebrae (T1–T12) i.e. upper back
•five lumbar vertebrae (L1–L5) i.e. lower back
•five bones (that are joined, or "fused," together in
adults) to form the bony sacrum
• three to five bones fused together to form the
coccyx or tailbone
In general a typIcal vertebra
consIsts of :
1.large vertebral body in the front
2.two strong bony areas called pedicles
connecting the vertebral body and the
3.an arch of bony structures in the back
(posterior arch) = (the spinous process).
2 specIal cervIcal vertebrea:
The atlas is the topmost vertebra
The Atlas has no body, and this is due to the fact that
the body of the atlas has fused with that of the next
vertebra (the Axis)
it has no spinous process, is ring-like, and consists of
an anterior and a posterior arch and two lateral masses
The second cervical vertebra
(C2) of the spine is named the
characteristic of this bone is the
strong dens which rises
perpendicularly from the upper
surface of the body.
The neural elements consist of the
spinal cord and nerve roots.
The spinal cord runs from the base of
the brain down through the cervical
and thoracic spine.
Below the L1–L2 level the spinal cord
ends, as an array of nerve roots
continues, looking somewhat like a
horse's tail (cauda equina).
At each vertebral level of the spine
there are a pair of nerve roots. These
nerves go to supply particular parts of
The intervertebral discs make up one fourth
of the spinal column's length. There are no discs
between the Atlas (C1), Axis (C2), and Coccyx.
Discs are not vascular and therefore depend on the
end plates to diffuse needed nutrients
are composed of two
parts: a tough outer portion and a soft
•The outer portion of the disc
(annulus fibrosus) composed of
concentric sheets of collagen fibers
that seal the gelatinous nucleus and
evenly distribute pressure and force
imposed on the vertebral column.
•The inner core (nucleus pulposus)
contains a loose network of fibers
suspended in a mucoprotein gel.
The outer portion and inner core of
the spinal disc fit together like two
interconnected by cartilaginous endplates
C. the supporting structures:
Ligaments are rope-like bands
of tissue that connect bones
together. Most ligaments are
lined up to keep joints from
bending in the wrong way
The most important ones are:
Anterior and posterior
Fas c i a:
Fascia is similar to ligaments,
but fascia is more like a sheet
than a rope.
The most important of which
is the thoracolumbar fascia
(TLF) which has the following
As the spinal muscles work,
the TLF pulls tightly the low
back, keeping the lumbar
spine from bending out of the
It augments the power
generated by spinal muscles.
M c l es :
Because of their location toward the
center of the body, and because of their
importance in spine stability, these key
stabilizers are called "core, paraspinal"
Core muscles help grip and hold the
spine. They keep each spinal segment
from shifting and sliding as you do
•Motor nerves signal the key muscles
to grip and hold and to guide and
control the spine.
•Sensory nerves transmit sensations
such as heat, cold, touch, pressure,
and pain. They also give us our
sense of position
Absorbs the shocks of walking on hard surfaces
More weight can be supported by a curved spine
than if it were straight
Additional space for the viscera is provided by the
concavities of the thoracic and pelvic regions.
Lastly, the S-curvature protects the vertebral
column from breakage
What are the functions
of the spinal column?
The major functions of the vertebral column are:
oProtection of the spinal cord.
oProviding stiffening for the body and attachment for the pectoral
and pelvic girdle and many other muscles.
oProviding motion for the human skeleton.
oThe S-curvature enables the vertebral column to absorb the shocks
of walking on hard surfaces