Spinal Injury

Question 1

what are spinal segments

Answer 1

section of the cord from which a pair of spinal nerves are given off

Question 2

what is spinal cord injury classification

Answer 2

Quadriplegia- injury in cervical region (all 4 limbs affected)
Paraplegia- injury in thoracic, lumbar or sacral segments (2 extremeties affected)

Question 3

Injury is either complete or incomplete. whats the difference between both

Answer 3

Complete injury- no information (ascending + descending tract) passing through the injured spinal cord level
Incomplete injury- there is some information passing through the injured spinal cord level

Question 4

what are the types of incomplete injury, describe them

Answer 4

central cord syndrome- typically in older patients, low velocity fall (periphery is preserved)
anterior cord syndrome - vascular abnormality as blood supply of SC in anterior
posterior cord syndrome
brown-sequard syndrome- usually due to penetrating injuries like stab wounds or gunshots
cauda-equina syndrome- bony compression or disc protrusions in lumbar or sacral regions

Question 5

what is the definition of spinal shock

Answer 5

temporary suppression of all reflex activity below the level of injury
occurs immediately after the injury

Question 6

which sign is one of the first reflexes to re-appear as spinal shock subsides

Answer 6

Babinski sign- stroking the foot
Normal- toes face downwards
Abnormal- toes face upwards

Question 7

what are the symptoms of spinal shock

Answer 7

Flaccid paralysis- muscle weakness and reduced muscle tone
Areflexia- muscles over-react to stimuli
Loss of sensation
Loss of bladder and bowel reflexes

Question 8

what are the phases of spinal shock

Answer 8

1. Areflexia (0-1 days)
2. Initial reflex return (1-3 days)
3. Initial hyperreflexia (1-4 weeks)
4. Hyperreflexia and spasticity (1-12 months)

Question 9

what is neurogenic shock

Answer 9

The body’s response to the sudden loss of sympathetic control, only parasympathetic control remains. Occurs in people who have spinal cord injury above T6 (>50% loss of sympathetic innervation)

Question 10

what is the clinical triad of neurogenic shock

Answer 10

Hypotension- due to decreased sympathetic tone- sudden massive dilation
Hypothermia
Bradycardia- results from unopposed vagal tone and exacerbates by hypothermia

Question 11

what is the surgical treatment for spinal injury

Answer 11

Acute spinal surgery

• allows stablisation
• decompression

Question 12

what are the long-term complications of immobilisation due to spinal cord injury ? what other respiratory complication may occur ?

Answer 12

pressure ulcers
Deep vein thrombosis
pulmonary embolism

pneumonia

Question 13

what is an upper and lower motor neuron lesion

Answer 13

UMN- lesion of the brain or spinal cord

LMN- lesion of the peripheral nerves

Question 14

what are the signsof UMN lesion

Answer 14

Muscle weakness
increased tone
increased reflexes

Question 15

what are the signs of LMN lesion

Answer 15

Muscle weakness and wasting
Reduced tone
reduced reflexes
fasciculations - involuntary muscle twitch

Question 16

How will injury to spinal cord level C3,4 and 5 result in respiration problems and what can be done to fix it

Answer 16

• C 3,4 and 5 gives rise to phrenic nerve
• phrenic nerve innervates the diaphragm (important muscle in respiration)
• if section above is damaged -> disconnection of all the motor neurons innervating the respiratory muscles from the respiratory centres in brain stem.
• -> breathing ceases so artificial ventilation is required

Question 17

How will injury to spinal cord level C6 and 7 result in respiration problems

Answer 17

• C6 and 7 innervates the intercostal muscles
• innervation to the diaphragm remains -> breathing remains intact
• > Paradoxical breathing

Question 18

Does damage to lower segments affect respiration

Answer 18

No

Question 19

if spinal damage is above lumbosacral region, then how is bladder control affected

Answer 19

Lumbosacral region escapes direct damage

• Reflex returns a few weeks following injury
• When the sensory bombardment of the cord from the stretch receptors in the bladder wall reaches a threshold, emptying is initiated -> automatic bladder

Question 20

after bladder control is problematic due to damage in lumbosacral region. how do patients indirectly control micurition

Answer 20

• As bladder fills, input to the cord from bladder wall stretch receptors produces reflex rise in BP by spinal mechanism
  BP regulation is deficient in the patient and hence the rise is greater than in normal people -> appears as flushing of face and signals patient to go to the toilet
• Scratching of thigh increases sensory bombardment of sacral region -> facilitates micturition reflex and bladder empties

Question 21

what does incomplete emptying of bladder leads to

Answer 21

increased risk of UTI

Kidney damage

Question 22

what is the management for bladder control

Answer 22

indwelling catheter or self-catheterisation

Question 23

how does somatic reflex return following spinal cord injury

Answer 23

Never regain voluntary control of skeletal musculature
o Reflex activity gradually recovers:
o Flexor reflexes return first: ankle, knee and hip in sequence
o Extensor reflexes return about 6 months after transection. Tend to be exaggerated leading to spastic paralysis
o Final stage is a predominant extensor activity with extensor spasms
o Extensor tendon reflexes are exaggerated –> hyperreflexia

Question 24

how does autonomic reflex return following spinal cord injury

Answer 24

• Mass reflex (autonomic dysreflexia) occurs- uncontrolled activation of both autonomic and somatic motor systems occurs e.g. any stimulation below the level of lesion results in flexor spasm, defecation and sweating

o Trivial stimulus to groin or soles of feet -> flexion of legs, defecation, micturition and erection in men -> socially embarrassing

o Profound sweating that can be triggered by cutaneous stimulation

o BP control remains more unstable than in normal people

o BP rises with filling of bladder -> stretch receptor bombardment

o Postural hypotension -> autonomic
compensation is inadequate –> BP falls and subject may faint

Question 25

How are motor and sensory information investigated for spinal injury patients

Answer 25

• Motor: ASIA charts

- Sensory: pin prick, light touch and sacral sparing

Question 26

what are symptoms of cauda equina syndrome?

Answer 26

leg numbness and weakness
bowel and bladder dysfunction
back pain
saddel parasthesia