Spinal Cord Injury Flashcards
what is the fx of the vertebrae?
provide bony support while still allowing mobility
what makes up the gray matter of the spinal cord?
Anterior horns- motor relay pathways
Posterior horns- sensory relay pathways
what makes up the white matter of the spinal cord?
Corticospinal tract: voluntary motor
Spinothalamic tract: pain sensation
Posterior columns: touch sensation
what can cause injury to spinal cord?
issues with blood supply to cord
why is it important to differentiate where in the sacral region injury occurred?
it determines bladder, bowel and sexual function/dysfunction
what does Injury to UMN destroy?
destroys cerebral influences or control over LMN (called UMNL- upper motor neuron lesion)
what does Injury to UMN result in?
spasticity (spastic paralysis)- loss of coordinated and integrated cerebral control over all reflex activity below level of injury
What does injury to LMN result in?
flaccid paralysis- destruction of the reflex arc breaks connection to intact UMN
what is the average age for SCI?
16-30
19 most freq
what does life expectancy depend on?
age at injury (and/or how long ago they were injured) Other complications (secondary issues) Severity of injury
what is the term for 4 limbs paralyzed? 2 limbs?
Tetraplegia
paraplegia
what are the causes for traumatic SCI?
MVA- most frequent- 37%
Falls
Violence
Sports injuries (most diving)
how does cancer cause a non traumatic SCI?
tumor within cord or in spinal canal pressing on cord
how does blood supply cause a non traumatic SCI?
Bleed from vessel into canal which takes up space + compresses spinal cord –> no blood supply
Occlusion of blood flow into cord i.e. due to blood clot or crush injury
what is a simple fracture of the vertebral column?
usually neural arch without injury to the spinal cord
what is a Compression or Wedge Fracture?
anterior compression injury to the vertebral body
what is a Comminuted or Burst Fracture?
shattering injury to the vertebral body;
fragments impinge on spinal cord; result in severe damage
what is a Teardrop Fracture?
small fragment chipped from vertebra;
lodges in spinal canal
associated with posterior dislocation of vertebral body
what is Dislocation/subluxation
of the vertebral column?
Vertebral bodies become displaced and can cause traction
Subluxation = partial dislocation
what is a Fracture/dislocation
of the vertebral column?
Describes a fracture and dislocation often associated with ligamentous and cord injury
what is the extent of a spinal cord injury based on?
Amount of force (how hard did injury take place)
Direction of force
Rate of application of the force
what is a flexion injury of the spine?
Forward bending that exceeds normal bending
what is the point of impact for a flexion injury?
Back of head
what is hyperflexion?
whiplash
what is the point of impact for an extension injury?
chin or face
what can cause a compression injury?
Spinal loading from blow to top of head or landing hard on your feet
when vertebrae are weakened by conditions like osteoporosis and cancer with bone metastasis
what level of the spinal cord does compression injury occur?
cervical level or thoracolumbar area
what is a axial-rotation injury?
Twisting tears fibers of spinal cord
causing very unstable injury
at what level of the spinal cord does axial rotation injury occur?
lumbosacral joint and at C1-C2 joint
Stability of sacrum with lots of movement on top
what can cause a penetrating injury?
gunshot, stab
burst or teardrop fracture where bone lodges itself in cord tissue
what can penetrating injury result in?
cord injury without vertebra (bone) injury and vice versa
what is a coupling injury?
multiple mechanisms for injury such as compression or traction with flexion/extension
(more mechanisms = more complication)
what occurs during a primary injury?
occurs at the time of the mechanical injury
small hemorrhage in gray matter followed by edema in white matter causing necrosis
what types of injury do primary injury involve?
compression, stretch, shear, and contusion
what does laceration cause?
primary injury to the cord with associated bleeding and edema
what is secondary injury?
increase the spread of injury, pathology that occurs following injury
what does secondary injury cause?
vascular- vessel trauma and hemorrhage; can lead to ischemia and edema
neural- loss of spinal reflexes below level of injury resulting in spinal shock, vaso spasm and further inhibit blood flow, increasing necrosis
how do you prevent further damage in secondary injury?
Anti-inflammatory medication
Open up space in vertebral canal so swelling has room to occur
what is an unstable injury?
when vertebral and ligamentous structure not able to support or protect injured area
Stability needs to be provided in order to heal
what determines a stable injury?
alignment and strength is maintained
No soft tissue damage and musculoskeletal system is intact
what is tetraplegia?
impairment or loss of motor and/or sensory function in the cervical segments of the cord due to damage of neural elements within the spinal canal
what does tetraplegia result in?
impairment of function in arms trunk, legs and pelvic organs (4 limbs)
what does tetraplegia not include?
peripheral nerve injuries
what is paraplegia?
impairment or loss of motor and/or sensory fx in thoracic, lumbar, or sacral (NOT Cervical) segments of spinal cord
what injured parts of spinal cord does paraplegia include? what does it not include?
conus medullaris and cauda equina injuries at tip of spinal cord
NOT peripheral nerves outside the spinal canal
what is complete SCI?
complete loss of all motor and sensory nerve transmission to areas below level of injury
what are the causes of complete SCI?
complete severance of cord
complete breakage of nerve fibers by stretching of the cord (coverings could be intact and cord may look normal)
complete ischemia of cord by interruption of total blood supply
Can have incomplete injury with lacerations not complete
what is incomplete SCI?
partial laceration or necrosis of spinal cord
Some info can get back and forth
What does the neurological assessment of SCI examine?
movement, sensation and reflex activity
what does the diagnosis of the neurological assessment describe?
level of vertebral fracture and extent of neurological deficit, to the last normal fxing segment of spinal cord
what does MMT detect?
changes in neurologic fx. gives info re: complete v. incomplete injury and level of injury
what do the sensory assessments detect?
changes in neurologic fx.
sensation organized in dermatomes that correspond with spinal nerves
what do the reflex assessments detect?
differentiation of upper motor neuron lesion and lower motor neuron lesion
what does the radiographic assessment document?
level of injury
what does the radiographic assessment provide info for?
info for level of stability of injury
what info does radiographic assessment not provide?
may not capture extent of bony displacement at moment of injury if the vertebrae has returned to normal alignment
what does the radiographic assessment demonstrate?
bone and soft tissue injury
alignment
what does CAT scan do?
outlines spine and perispinal structures clearly
what does MRI do>?
direct imaging of soft tissues, ie the cord, ligaments and intervertebral discs
what is emergency care of SCI?
stabilization for transport
breathing- ventilator support may be needed
what is post emergency care of SCI?
primary goal following ABC’s: decompress the spinal cord by realignment of the spinal canal
closed reduction through skeletal traction
surgical reduction with internal skeletal stability
what is spinal shock?
interruption of sympathetic nervous system
what is neurogenic shock?
body’s reaction to sudden interruption of central nervous system control
what are symptoms of spinal shock?
hypotension
bradycardia
hypothermia
what is hypotension?
low blood pressure, caused by passive vasodilation of the systemic vascular network below level of injury,
decreased circulating blood volume and decreased cardiac output
what is bradycardia?
slow pulse
what is hypothermia?
body’s instability secondary to lack of vasomotor control hampers body’s ability to conserve body heat
why does spinal shock occur?
Body’s effort to stay alive after injury
what is cervical surgery?
internal surgery
decompress spinal canal by removing all bony and soft tissue elements pressing against spinal cord
obtain immediate stability for patient movement- via posterior approach using wires and bone grafts
how are wires and bone grafts used?
wiring of spinous processes
graft using bone from iliac crest, fibula or tibia
plates and screws
what is Thoracolumbar surgery?
internal stabilization technique using rods and/or fusion; sometimes screws and plates
when is a harrington rod used/
when stability needed after spinal cord injury after fall or trauma
when are bigger rods used?
scoliosis
when is fusion surgery used?
for stability
what are methods of external stabilization?
immobilization bed
Cervical Traction/Support
what are the tools used in cervical traction?
Tongs (attached to skull used to figure out what to do) or calipers
Halo- rigid brace used later, after cervical traction with tongs
what kind of maintenance is needed for cervical traction?
maintenance of pin sites, traction
what are contraindications of a halo?
severe respiratory problems, chest injuries and burns on trunk or abdomen
what are examples of external cervical supports?
Semi-rigid cervical orthosis
Cervical collar: more rigid
what are examples of Thoracic and Lumbar Traction/Support?
Traction
Thorocolumbar orthosis
what is autonomic dysreflexia?
sudden severe headache secondary to an uncontrolled elevation in BP
what is autonomic dysreflexia caused by?
stimuli creating exaggerated response of the sympathetic nervous system
i.e. Over-distended bladder, bowel impaction, urinary infection
when does autonomic dyreflexia occur?
mainly when T 4-6 or higher injury
how do you tx autonomic dysreflexia?
remove the aversive stimuli
what is Orthostatic or postural Hypotension?
Dramatic fall in BP when upright posture is assumed due to Disturbed vasomotor control with decreased blood supply returning to heart
when does orthostatic hypotension occur?
injury T4-6 or higher, with increased incidence at higher levels.
what is Deep Vein Thrombosis?
Development of a blood clot in the venous structures that Can lodge in heart, lungs, brain causing death
how do you tx deep vein thrombosis?
Clot meds, surgery
how do you prevent another deep vein thrombosis?
compression garments
What is heterotropic ossification?
bone grows where it shouldnt causing signs of localized inflammation or pain, elevated skin temp, etc.
where does heterotropic ossification usually occur?
major joint i.e. hip, knees, shoulders, elbows
where does heterotropic ossification occur in spinal cord?
below level of injury
how do you tx heterotropic ossification?
meds, radiation, operative resection (still risk recurrence), needs to run its course or surgery
