Spinal Anatomy Flashcards
what is the function of the spine?
to provide movement, support, and protection
what are the 5 regions of the spine?
cervical region, thoracic region, lumbar region, sacrum, coccyx
describe the cervical region
C1-C7 vertebral bodies
supports the weight of the head
describe the thoracic region
T1-T12 protects the organs of the chest
limited range of motion
describe the lumbar region
L1-L5 bears the weight of the body
describe the sacrum
5 fused vertebrae
provides attachment for the hip bones and protects pelvic organs
describe the coccyx
4 fused bones without function
spinal balance
comes from the sagittal curves so that the body can stay upright and provide support for the weight of the head, body, and forces of gravity
lordosis
the natural curve in the cervical region and lumbar region when viewed laterally
kyphosis
the natural curve of the thoracic region (opposite lordosis)
vertebral body
anterior facing, designed to bear weight and withstand compression
posterior elements of the vertebra
multiple processes designed as points for soft tissue attachments
pedicle, lamina, transverse process, inferior articular process, superior articular process, spinous process
facet joints
each vertebra has two sets of facet joints
one pair faces upward (superior facet), one pair faces downward (inferior facet)
one joint on each side left and right
facet joints are hinge-like and link vertebra together located at the back of the spine (posterior)
facet joints allow motion of what kinds?
flexion - bending forward
extension - bending backward
twisting motion
spinous process
each vertebra has a protrusion on its backside called the spinous process
it extends backward and slightly downward
this is where the ligaments and muscles attach to the vertebra
C7 characteristics
The 7th vertebra in the cervical region
it has the most prominent spinous process and is what you feel when you touch the back of your neck
thoracic vertebra characteristics
vertebral body is heart-shaped
presence of superior / inferior costal facets of the sides
the spinous processes are long and slant downward which offers increased protection to the spinal cord preventing something like a knife from entering the spinal cord
lumbar spine characteristics
L1-L5 largest in the spinal column
Designed to be incredibly strong, protecting the highly sensitive spinal cord and spinal nerve roots
Highly flexible providing for mobility in many different planes including flexion, extension, side bending and rotation
Most people have 5 vertebra in the lumbar spine but it is not unusual to have 6
Vertebral bodies are large and kidney shaped
sacrum characteristics
lies between L5 and the coccyx
triangular shaped bone consists of 5 segments fused together
the first 3 vertebra come together to form a wing called alae
this area of the spine is subject to a lot of stress and twisting which can lead to injury
coccyx characteristics
most caudal portion of the spinal column
contains 4 or 5 bones that are typically fused
functionally insignificant
spinal nerves
there are 31 spinal nerves, the cervical region has 8 nerves, thoracic 12 and lumbar 5
nerve injury
injury to the spinal cord will often be permanent
injury to the nerve roots or cauda equina usually have a much better prognosis
typically a spinal injury is classified as complete or incomplete
complete lesions
characterized by a total loss of motor, sensory and reflex functions below the level of injury
complete cord injuries are named by the last functioning nerve root
incomplete lesions
some function
Grade A Complete Neurologic injury
no motor or sensory function detected below level of lesion
Grade B Preserved sensation only
no motor function detected below level of lesion, some sensory function preserved
Grade C preserved motor, nonfunctional
some voluntary motor function but too weak to serve any useful purpose, sensation may or may not be preserved
Grade D preserved motor functional
functionally useful voluntary motor function below level of injury
Grade E normal motor function
normal motor and sensory function below the level of lesion
abnormal reflexes may persist
