Anatomy of the spine - Hastaneciyiz's Blog

Download Report

Transcript Anatomy of the spine - Hastaneciyiz's Blog

Anatomy
of the spine
Medical ppt http://hastaneciyiz.blogspot.com
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
cord.
At Birth
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
discs)
•neural elements (i.e., the spinal
cord and nerve roots)
•supporting structures (e.g., muscles
and ligaments)
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 intervertebral discs.
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
posterior arch
3. an arch of bony structures in the back
(posterior arch) = (the spinous
process).
BODY
PEDICLE
spinous process
transverse
process
2 special cervical vertebrea:
1. Atlas:
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
2. Axis:
The second cervical vertebra
(C2) of the spine is named the axis
The
most
distinctive
characteristic of this bone is the
strong
dens
which
rises
perpendicularly from the upper
surface of the body.
B. Neural Elements:
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 body.
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
Discs
are composed of two
parts: a tough outer portion and a soft
inner core:
•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
concentric
cylinders
and
are
interconnected by cartilaginous endplates
C. the supporting structures:
1. Ligaments
1. Fascia
1. Muscles
1. Nerves
Ligaments:
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:
1.
2.
3.
Anterior and posterior
longitudinal ligaments
Ligamentum flavum
Intervertebral discs
Fascia:
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
functions:
As the spinal muscles work,
the TLF pulls tightly the low
back, keeping the lumbar spine
from bending out of the
neutral position.
It augments the power
generated by spinal muscles.
Muscles:
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" muscles
Core muscles help grip and hold the
spine. They keep each spinal segment
from shifting and sliding as you do
your activities
Nerves:
•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
‫واااااحد‬
Medical ppt http://hastaneciyiz.blogspot.com