Spinal Anatomy, Assessment, Injuries: Cervical Fractures, SC injuries, Cauda Equina

Question 1

Epidemiology of spinal trauma

Answer 1

More common in men
Age peaks in 20s
Majority are cervical

Question 2

Vertebral anatomy

• no of CTLS vertebrae
• SC end

Answer 2

C1-7
T1-12
L1-5
S1-4

Nerve roots go above the vertebrae until C8
Then go under

SC ends between L1-2 in adults, L3 in children

Question 3

CS tract

• functions
• decussation
• location in cord
• consequences of injury

Answer 3

Motor
BS/medulla

Posterolateral to dorsal horn

Ipsilateral motor loss

Question 4

ST tract

• functions
• decussation
• location in cord
• consequences of injury

Answer 4

Pain, temperature
On entry into cord

Anterolateral to ventral horn

Contralateral pain, temperature loss

Question 5

Dorsal columns

• functions
• decussation
• location in cord
• consequences of injury

Answer 5

Vibration, proprioception
BS/medulla

Posterior

Ipsilateral loss of vibration, proprioception

Question 6

Describe the presentation of primary spinal cord injuries

Answer 6

Central cord - CST damaged

• can walk into the pub, cannot pick up a drink (bilateral upper M, S loss)
• hyperextension injury

Anterior cord - ST, CST damage

• loss of ipsilateral CS below lesion
• loss of contralateral ST below injury
• dorsal preserved
• flexion/vascular injury

Brown Sequard - hemisection damage

• ipsilateral CS, dorsal loss
• contralateral ST loss
• penetrating trauma

Question 7

Types of spinal cord injury and their properties

• primary
• secondary

Answer 7

Primary - immediate effect

• compression, contusion, shearing
• unless penetrating trauma, SC looks normal immediately afterwards
• unavoidable damage

Secondary - minutes => hours

• ischemia, hypoxia, inflammation
• progressive neurological deterioration
• preventable damage

Question 8

Neurogenic shock vs spinal shock

• pathophysiology
• BP
• HR
• motor effects

Answer 8

Neurogenic - disruption of autonomic pathways => loss of SNS, vasomotor tone

• systemic low BP, HR, temp
• resp insufficiency
• flushed skin

Spinal - temporary unresponsive peripheral neurons

• flaccid paralysis
• no reflexes, sensory, motor function

Question 9

Types of possible cervical spine fractures

Answer 9

C1
Jefferson fracture - axial loading of occipital condyles into lateral masses of C1

C2
Odontoid process fracture - common in older patients
-low impact injury, present with neckpain
-can cause severe head, SC instability

Hangman fracture
-cervical hyperextension => pars interarticularis fracture

Question 10

Types of possible thoracic spine injuries

-how would you assess instability

Answer 10

Most common cause

• osteoporosis
• follower by trauma

3 column model

• ant column - ALL => central body
• middle column - central body => PLL
• post column - PLL => SL, IL

Wedge - compression of anterior part of vertebral body
Burst - compression from above
Dislocation - part of spinal column breaks away
Seatbelt - forceful flexion

Question 11

Cauda equina

• Pathophysiology
• Most common cause

Answer 11

Cauda equina nerves compressed
Most common cause = disc prolapse L4/5, L5/S1
-tumours
-infection
-trauma, hematoma

Question 12

Cauda equina

• presentation
• investigations
• management

Answer 12

New, worsening severe low back pain
Bilateral sciatica - shooting pains down both legs when stretched
No LL reflexes, weak
Leg weakness, loss of reflexes,
Saddle anaesthesia- numb when wiping
Decreased anal tone => fecal, urinary incontinence
Erectile dysfunction
Prevoid bladder and postvoid bladder scan => residual urine in bladder due to inability to sense fullness

Urgent MRI

Initial - dexamethasone
Definitive - surgical decompression

Question 13

Immobilisation of patients

• when would you do this?
• how would you do this?

Answer 13

Full in-line spinal immobilisation if

• spine pain
• drunk/confused/uncooperative
• significant distracting injuries => causes more pain than spinal pain
• GCS U15
• hand/foot weakness/sensation changes
• Hx of past spine problems
• high risk for Cspine injury
• low risk but unable to actively rotate neck

Logroll - 5 people needed (1 head, 3 body, 1 leg)
Cervical collar
Inline manual stabilisation
3 blocks

Question 14

When would you do a

• CT CSpine 1hr of risk being identified
• Xray CSpine 1hr of risk being identified

Answer 14

HIGH RISK FACTORS
-GCS U13 initially
-Intubated
-Xray not normal/not possible
-Definitive diagnosis needed urgently
Suspicion of CSpine injury AND
-65+
-dangerous MOI
-focal neuro deficit/paraesthesia in limbs

Head injury + neck pain/tenderness AND

• not safe to assess neck mv
• cannot actively mv neck 45deg

If Xray not normal/possible => CT

Question 15

Factors for neck injury

• high risk
• low risk

Answer 15

High risk
-CT CSpine 1hr factors

Assess neck mv if NO HIGH RISK + LOW RISK
-simple rear end vehicle collision
-sitting comfortably/ambulatory
-no CSpine tenderness
-delayed neck pain
=> assess neck mv

Question 16

When would you consider CSpine imaging

Answer 16

Radiographs needed

• MOI high risk
• Distracting injuries
• Confused
• Spine pain
• Cannot actively move head due to pain

Radiographs not needed
-No pain on rest and active movement

Question 17

Types of imaging used in spinal injuries

Answer 17

XRay

• Cervical - AP, lateral, open mouth (see peg and dens, lateral masses
• Thoracolumbar - AP lateral

CT - best for bones

• suspected spinal injury/focal neurology with normal Xray
• also when doing CT head

MRI - best for SC

Question 18

How to assess cervical spine radiographs

Answer 18

There should be 4 straight lines that you can follow down from base of skull - T1

• ant body of spine
• post body of spine
• spinous lamellae
• spinous processes

If there is any discontinuity => injury

Less ant spinous body tissue at top of CSpine than bottom normally
-if not => hematoma?