Spinal Cord Injuries Flashcards
brief CNS and sc refresher -
Sc is our motor way of information
Sc sits within the bony protection of the spinal column surrounded by protective tissue - dura
Nerve roots emerge from the vertebral foramen at each segment level
Ascending and descending pathways/tracts
Afferent sensory tracts
Dorsal column -
Fine touch
2 point discrimination
Vibration
Conscious
Proprioception
Afferent sensory tracts
Spinothalamic -
Pain
Course touch/ pressure
Temperature
Afferent sensory tracts
Spinocerebellar -
Proprioception (unconscious)
Coordination
Descending motor tracts
Corticospinal tract -
Rubio spinal -
Cortico - voluntary conscious movement
Rubio - tone-manly flexors of upper limb
Descending motor tracts
Retiiculopsinal -
Vestibulospinal -
Tectospinal -
Reticulopsinal - tone, postural axial tone, resp/circulator systems
Vestibulospinal - extensor activity
Balance and posture
Tectospinal - auditory and visual stimuli
Autonomic NS
Parasympathetic, what does it do?
Rest and digest
Constricts pupils
Stimulates saliva flow
Slows heart rate
Constricts bronchi
Stimulates stomach, pancreas and intestines
Stimulates bile release
Contracts bladder
Autonomic NS
Sympathetic - what does it do?
Fight or flight
Dilates pupils Stimulates saliva
Inhibits saliva flow
Accelerates hr
Dilates bronchi
Stimulates stomach, pancreas and intestines
Converts glycogen to glucose
Secretes adrenaline
Inhibits bladder contraction
Background and stats of SCI in the uk:
Approx 105,000 people in uk live with a SCI
Previously, predominantly young male individuals
1.5:1 male:female
Demographics are changing, seeing an increase in proportion of elderly population
Causes of SCI
Traumatic: 3 different mechanisms -
1) destruction - from direct trauma
2) compression - by bone fragment, hematoma or disc material
3) ischaemia - from damage or impingement on spinal arteries
Causes of SCI
Non-traumatic -
Degenerative disc disease and spinal canal stenosis
Spinal infarction
Tumour
Inflammation of spinal cord
Viral infection
Developmental/ congenital abnormalities
Types of SCI
Complete -
Complete loss of function below the injury
Motor
Sensory
Auntonomc dysfunction
- postural hypotension - vast motor control
Autonomic dysreflexia - medial emergency, response to stimuli resulting in sudden increase in BP and decrease in HR
- problems with bladder and bowel function
- problems with sexual function
Types SCI
Incomplete -
Some sparing of neural activity below the level of the lesion
4 main types
Types SCI
Tetra/quadraplegia -
Impairment at cervical segments of the cord
Affects all four limbs - upper and lower
Types SCI
Paraplegia -
Impairment at thoracic, lumbar or sacral segments of the cord
Involving lower limbs
Depending on level of injury , trunk, legs and pelvis may be involved
What are the vulnerable areas of the vertebral column?
Cervical spine - typically C5-7, bc of weight of head and pivot point
Thoracolumbar, typically T12 - often from falling
Majority of traumatic cases are due to dislocation
Incomplete SCI
Central cord syndrome -
Motor dysfunction in upper limbs
Bladder dysfunction
Corticospinal and spinothalamic tracts
Cause - hyperextension injury to neck
Incomplete SCI
Anterior cord syndrome -
Motor paralysis below leison
Loss of pain and temperature sense
Retained proprioception and vibration
Cause - disc herniation
Incomplete SCI
Brown-sequard syndrome -
Motor deficit and numbness to touch and vibration on same side of leison
Loss of pain and temperature sensation on opposite side (because of tracts crossing at different levels)
Most common cause - stab or gunshot wound to cervical or thoracic spine
Incomplete SCI
Posterior cord syndrome -
Sensory disturbance and less motor loss
Compression to posterior/sensory section of spinal cord
Cause - posterior impact or hyperextension trauma
InComplete SCI
‘Special one’ to make a 5th type - Cauda equina syndrome -
Lower motor neurone lesion
Motor and sensory loss in lower limbs Bladder dysfunction
Saddle anaesthesia, bilateral lower limb sensory changes
Causes - lumbar stenosis, spinal trauma, metastatic tumour
Incomplete SCI
Cauda equina - immediate medical management -
Following trauma, treatment begins with stabilisation
Need to have normal oxygenation, perfusion and acid/base balance to aid management of the injury
Vasogenic oedema and altered flow account for clinical deterioration - hypotension and shock can aggravate SCI
Surgical intervention - possibly decompression, removal of foreign body stabilise the spine
Alongside medical management of any other trauma sustained
Post acute management of CES - (of complications)
Urinary and bowel management
Skin integrity (pressure sores)
DVT
Autonomic dysreflexia (at or above T6)
Orthostatic hypotension (postural hypotension)
What is autonomic dysreflexia?
S+s -
Life threatening condition
It is an uninhibited sympathetic nervous system response to a variety of noxious stimuli occurring in people with spinal cord injury at T6 level or above
S+s - raised BP, bradycardia, pounding headache, flushing, sweating or blotching above level of injury: pale, cold, goosebumps below level of injury, anxiety or apprehension
Seek urgent medical support and remove/ relieve noxious stimulus if possible
Defining the level of the lesion -
Eg, with loss of biceps -
Define the level of injury as the first spinal segmental level that shows abnormal neurological loss
Eg person has loss of biceps (C5), the motor level of injury is often said to be C4
What scale can be used asses sensory and motor levels? How does it work?
ASIA impairment scale
(American spinal injury association scale)
5 levels - A-E
A- complete, no motor or sensory function is preserved in sacral segments S4-S5
B- incomplete, sensory but not motor function preserved
C- imcomplete, motor function preserved below neurological level and more than half of key muscles below grade less than 3
D- incomplete, same as above but muscles grade more than a 3
E - normal - motor and sensory function are normal
ASIA and Myotomes and Dermatomes
C5 -
C6 -
C7 -
C8 -
T1 -
C5 - shoulder abd/LR, elbow flexors
C6 - wrist extensors/flexors, pron/sup
C7 - shoulder add/MR, elbow extensors
C8 - finger flexors/ext
T1 - finger abduction
ASIA Myotomes and Dermatomes
L2 -
L3 -
L4 -
L5 -
S1 -
S4-5 -
L2 - hip flexors
L3 - knee extensors
L4 - ankle dorsiflexion
L5 - long toe extensors
S1 - ankle plantar flexors
S4-5 - anal sphincter
Diagnosing SCI
Differential diagnosis -
What presents in a similar way?
Diagnosis is based on patients presentation
However, broader differential must be considered for sensorimotor weakness when the insert and preceding events are unclear
Other pathologies leading to sensorimotor loss/weakness:
Central NS pathologies - stoke, MS
Neuromuscular junction - myasthenia gravis and botulism
Peripheral nerve - Gillian-barre syndrome, transverse myelitis
Other - hypoglycaemia and diabetic neuropathy
Spinal nerve root action in relation to vertebrae
C1-3 -
C4 -
C1-3 - limited head control
C4 - breathing and shoulder shrug
Spinal nerve root action in relation to vertebrae
C5 -
C6 -
C8 -
C5 - lift arm with shoulder, elbow flex
C6 - elbow flex and wrist ext
C8 - finger flexion
Spinal nerve root action in relation to vertebrae
T1 -
T2-T12 -
T6-L1 -
T1 - finger movement
T2-12- deep breaths, deep breathing
T6-L1 - deep exhale of breath, stability whilst sitting
Spinal nerve root action in relation to vertebrae
L1-2 -
L2-3 -
L3-4 -
L1-2 - hip flexion
L2-3 - hip movement towards middle of body
L3-4 - knee extension
Spinal nerve root action in relation to vertebrae
L4-5 -
L5 -
L4-5 - ankle extension
L5 - extension of big toe
Spinal nerve root action in relation to vertebrae
S1 -
S1-2 -
S2-4 -
S1 - movement of foot and ankle
S1-2 - toe movement
S2-4 - function of bladder and bowel
Ascending tracts transmit -
Descending tracts transmit -
The two sections of autonomic NS-
Ascending - sensory
Descending - motor
Autonomic sympathetic and parasympathetic
What are the sages of autonomic dysreflexia?
SCI level t6 or above
1) catheter blockage for eg, stimulus below level of injury, too much urine in bladder
2 stretched bladder sends nervous impulses to the spinal cord
3) when impulses reach level T6,sympathetic neurones become activated and release chemicals called norepinephrine.
4) causes blood vessels in skin and abdomen to constrict. BP rises
*sudden increase in BP is medica emergency as can lead to strokes, seizures or even sudden death
5) rise in BP detected by sensors in heart and neck (baroreceptors) these send signals to brain
6) 2 ways brain can oppose rise in BP. First, sends messages via parasympathetic vagus nerve to heart to slow is down
7) brain sends messages down SC making blood vessels open up
Cord injury prevents messages, only blood vessels above injury dilates. It’s not enough to overcome constricted vessels below injury level, therefore BP continues to rise
and HR remains slow
