SCI Flashcards
How many cervical nerves are there?
8
How many thoracic nerves?
12
How many lumbar nerves?
5 pairs
What are lower motor neurons?
Begins in the spinal cord, and goes to innervates muscles
What is a myotome?
the muscles that each spinal nerve innervates
What is a dermatome?
the area of the body that each spinal nerve gathers sensory information from
People with complete injuries below T12-L1 are unlikely to experience spasticity.
True
What is the neurotransmitter of upper motor neurons?
Glutamate
What is the neurotransmitter of lower motor neurons?
acetylcholine
What are descending tracts?
information is traveling from the brain down the spinal cord to other parts of the body.
What are ascending tracts?
information coming from areas in the periphery and going up to the brain.
sensory pathways that begin at the spinal cord and stretch all the way up to the cerebral cortex
What is the corticospinal tract (pyramidal)?
UMN from cortex to spinal cord
What does the lateral corticospinal tract control? (Descending track)
Control of limb muscles
What does the ventral (anterior) corticospinal tract control? (Descending track)
Control of axial (trunk) muscles
What does the vestibulospinal tract (descending track) do?
Innervates extensor and axial muscles; involves balance control and posture
What is the main action of the reticulospinal tract? (Descending track)
to dampen down activity in the spinal cord. Without this path way, there is increased extensor tone observed
What is the tectospinal tract responsible for? (Descending track)
reflex turning of head in response to sights and sounds (superior collicus)
What is the superior collicus?
structure in the midbrain that is part of the brain circuit for the transformation of sensory input into movement output.
What does the lateral spinothalamic tract carry? (Ascending track)
information about pain and temperature
Although pain signals travel through this tract to the thalamus and eventually reach the cortex, you don’t consciously experience pain until these signals arrive in the cerebral cortex, where they are processed.
What does the ventral spinothalamic tract carry? (Ascending track)
information about pain, temp, crude touch. To the thalamus
What is the dorsal column pathway? (Ascending track)
The largest ascending tract, conveys proprioception, fine touch and vibration.
How are SCI a bimodal distribution?
See lots of injuries in young age (MVA, sports) and lots in older age (falls)
Spinal cord injury
Defined as damage to the spinal cord that temporarily or permanently causes changes in its function.
Traumatic vs non-traumatic SCI?
- Traumatic SCI = due to external physical impact
- Non-traumatic SCI = due to acute or chronic
disease process
What is an incidental finding?
looking for something else on imaging but come across something that may cause symptoms soon in Non traumatic spinal cord injury
What is decompression surgery?
Want to reduce swelling to decrease pressure to limit further damage –> take a drill and slightly expose spinal cord so it can expand out the back
What is central cord syndrome?
typically affecting the cervical region. It results in disproportionate upper extremity weakness and fine motor control loss compared to the lower extremities.
What is Brown-Sequard Syndrome?
Motor function is weak on that side below the level of injury. Proprioception and light touch will be affected on same side. Pain and temperature will be affected on the other side due to cross over.
What is anterior cord syndrome?
results in a loss of motor function, pain and temperature sensation below the level of the injury, while preserving proprioception and vibration sense.
Dorsal column is in tact
Damage to blood vessels, no blood supply to a specific area
What is posterior cord syndrome?
impaired proprioception, vibration sense, and fine touch sensation, while motor function and pain and temperature sensation are preserved.
What spinal levels are associated with sympathetic preganglionic?
T1-L2
What happens with a T1-T5 injury?
May be hard to achieve predicted HR max with Autonomic Nervous System
Injury above, t6, inervation of the heart will be compromised
What is the risk of injury at T6 level or above?
puts an individual at a higher risk for autonomic dysreflexia
Where would sweating happen in an injury?
Above level of injury
If injury at T6 , they will not be able to sweat below that level, thermo regulation will be affected
Why does parasympathetic innervation of the heart not get affected in an ANS injury?
Parasympathetic innervation of heart occurs in brain stem which is typically above injuries but we cannot balance the heart system due to sympathetic system being interrupted from injury.
Where are preganglionic cells located?
In spinal cord in grey matter
How does disruption of sympathetic outflow limit aerobic exercise?
Cardiovascular impairment:
1. HR
2. Contractility (SV)
3. Venous blood pooling in lower limbs (less venous return)
What is the Autonomic Standards Assessment Form?
Check autonomic function and give a score
Heart and blood pressure
- Laying down vs sitting up, it’s normal for changes, if it does not change, there is an issue
What is autonomic dysreflexia?
- An over-activity of the Autonomic Nervous System
- an irritating stimulus is introduced to the body below the level of spinal cord injury (overfull bladder)
- stimulus sends nerve impulses to the spinal cord, where they travel upward until they are blocked by the lesion at the level of injury
- since the impulses cannot reach the brain, a reflex is activated that increases activity of the sympathetic portion of autonomic nervous system
- this results in spasms and a narrowing of the blood vessels, which causes a rise in the blood pressure
- nerve receptors in the heart and blood vessels detect this rise in blood pressure and send a message to the brain
- the brain sends a message to the heart, causing the heartbeat to slow down and the blood vessels above the level of injury to dilate
- however, the brain cannot send messages below the level of injury, due to the spinal cord lesion, and therefore the blood pressure cannot be regulated
Should we lay people down or sit people up if they are experiencing autonomic dysreflexia?
Don’t lay people down as it increases pressure in the head
- Figure what is triggering it. Can be anything causing pressure but usually bowel or bladder distention
What are the signs and symptoms of autonomic dysreflexia?
- Increased BP
- Decreased HR (irregular)
- Sweaty above injury level
- Headache
- Anxiety
- Blurred Vision
What is the response to autonomic dysreflexia?
- Sit Upright (Orthostatic Hypotension)
- Loosen clothing, monitor HR/BP (something tight might be the issue)
- Look for stimulus, bladder distension, kink in catheter, pressure sores
- Seek treatment if BP remains elevated
What are the facts about autonomic dysreflexia?
90% of people affected if injury above T6; 20-40mmHg above person’s typical systolic
What is the pathway of autonomic dysreflexia?
Vasoconstriction is happening below level of injury, elevating blood pressure detected by baroreceptors. Cervical nerves then attempt to slow heart rate but descending signals to inhibit HR is blocked
What is the International Standards for Neurological Classification of Spinal Cord Injury (ISNCSI)?
Main neurological outcome measure in clinical trials.
What is the process of sensory (dorsal column tract) for ISNCSI?
Test dermatome that corresponds with certain spinal cord location.
2 test, light touch and pin prick
Light touch test
Light touch
(Q1) Can you feel me touching you
* if it’s no, there will be a zero in that column,
* if the answer is yes, move to Q2
Q) Does it feel the same as your face
* if it’s yes , they get a 2
* If it’s no, then you get a 1
Eyes closed when doing light touch
Touching both face and the selected area
Pin Prick test
Pin prick
(Q1) is this sharp or dull
* if it’s accurate move to Q2
* if they are not accurate they get a zero
Q) Does it feel the same as your face
* if it’s yes , they get a 2
* If it’s no, then you get a 1
Eyes closed when doing pin prick
Touching both face and the selected area
Texting sharp or dull
Do the test at least ten times
Motor test
Motor test
Provide resistance, expecting different results based on the individual (age)
What is the pain (nociception) process for ISNCSI?
Poke the cheek with a pointy pin and blunt end, then do with eyes closed to see if they can tell difference.
What does a ‘Yes’ response for pain (nociception) for ISNCSI mean?
Have to be right 9/10 times. Score of 2.
What are we trying to determine in ISNCSI?
Trying to determine where do scores go from 2 to something different—-> tells us which possible neurological location is affected
What does a score of 5 in ISNCSI motor test indicate?
Normal or expected. Full range of motion
What does a score of 4 for ISNCSI motor test indicate?
Muscle strength and can actively move a specific muscle group against gravity and somewhat against moderate resistance.
What does a score of 3 in motor test for ISNCSI indicate?
Can move it against gravity but not additional resistance.
What does a score of 2 in motor test for ISNCSI indicate?
Can’t move it against gravity but can move it with support.
Full range of motion if Gravity is eliminated