Spinal Trauma

Spinal Trauma

DEFINITION
ATLS Notes at top and Jerome's part II notes at bottom.
See C-Spine card for notes specific to C-spine.

D E A B M I M

EPIDEMIOLOGY
Up to 15% of pts with an injury above the clavicle have a c-spine injury.

Of spinal injuries:
55% are cervical
15% are thoracic
15% are thoracolumbar jx
15% lumbosacral.

Injury associations
5% of head injuries have associated spinal injury.
25% of spinal injuries have at least a mild head injury.

D E A B M I M

AETIOLOGY
Trauma
D E A B M I M

BIOLOGICAL BEHAVIOUR

Anatomy / Physiology
Pathophysiology
Classification

Anatomy

Bones
Anterior vertebral body is the main weight-bearing column.
Ant & post longitudinal ligs hold together vertebral column & discs.
Posterolateral pedicles support the laminae which together house the vertebral canal.
Facet jts, interspinous ligs, and paraspinal muscles all help stabilise the spine.

Spinal Cord
Ends at L1 in an adult.
- below this the cauda equina is more resistant to injury.
Only 3 tracts can be readily assessed clinically:
1. Corticospinal:
(Posterloateral)
Motor supply to same side.
- test by voluntary movement or response to pain.
2. Spinothalamic:
(Anterolateral)
Pain and temp sense from opposite side.
- test by pinprick and light touch.
3. Posterior columns:
Position sense (proprioception), vibration and some light-touch from same side.
- test by position sense or vibration.

Dermatomes
Used to determine level of spinal injury.
Sensory level: lowest dermatome at which normal sensory fx occurs - can differ by side.
- C1-4 are somewhat cariable and not commonly needed.
- however C2-4 supply the 'cervical cape' over the pectoralis via supraclavicar nerves.
C5 = deltoid area
C6 = thumb
C7 = middle finger
C8 = little finger
T4 = nipple
T8 = xiphisternum
T10 = umbilicus
T12 = symphysis
L4 = medial aspect of leg
L5 = space b/n toes 1-2.
S1 = lateral border of foot
S3 = ischial tuberosity area
S4-5 = perianal.

Myotomes
C5 = deltoid
C6 = wrist extensors
C7 = elbow extensors
C8 = middle finger flexors
T1 = abductor digiti minimi
L2 = hip flexors
L3 = knee extensors
L4 = ankle dorsiflexors
L5 = big toe extenosrs
S1 = plantarflexors

Pathophysiolology

C-spine is more mobile and more prone to injury.
- see C-spine card for more detail.
T-spine is less mobile and supported by rib cage, hence injury much lower and more likely simple compression fractures.
- however when #-dislocation does occur, complete neurological injury more likely due to narrow thoracic canal dimensions.
Thoracolumbar jx is a fulcrum point and more vulnerable to injury.

Neurogenic Shock
Impairment of descending sympathetic pathways.
Loss of vasomotor tone +/- sympathetics to heart.
--> hypotension, bradycardia or failure to enter compensatory tachycardia.
BP will not respond to fluid alone
--> judicious use of vasopressors
--> perfusion may be ok with a low BP
--> atropine may be needed for bradycardia

Spinal Shock
Flaccidity / loss of reflexes in spinal cord injury.
Although may appear completely functionless, all areas may not be destroyed.
- duration of this state variable.

Other systemic effects
Paralysis of intercostal muscles.
C3,4,5 damage may cause diaphragmatic paralysis.
Loss of pain sense may mask injury to eg abdomen.

Classification

Level
The most caudal segement with normal function on both sides.
- sometimes just a sensory or motor level (power at least 3/5) is discussed.
- there may be a lower zone of partial preservation.
Bony level refers to site of bone damage (less important).
- may not agree with neurological level, especially more caudally.
Quadraplegia results from injuries to first 8 segments
Paraplegia to lesion below T1.

Severity
Complete when no sensory / motor below a certain level.
- deep tendon reflexes or sacral reflexes (eg anal wink / bulbocavernosus) may be preserved.
Incomplete when any fx remains.
- significantly better prognosis for recovery.
- may include any sensation / position sense / movement.
- perianal sensation (sacral sparing) may be the only sign of residual function: test by sense in perianal region or voluntary contraction of the rectal sphincter.

Cord Syndromes

Central Cord Syndrome
Usually hyperextension in preexisting cervical canal stenosis.
- with or without C-spine # / dislocation.
--> vascular compromise in distribution of anterior spinal artery.
--> ischaemia of central portion of cord, where cervical segments congregate.
Disproportionately greater motor loss in upper vs lowever extremities.
- varying degree of sensory loss.
Prognosis relatively good: legs usually reover first, then bladder, then arms, then hands.

Anterior Cord Syndrome
Infarction in area supplied by anterior spinal artery.
Paraplegia, dissociated loss of pain/temp sensation.
- posterior column preserved (position, vibration, deep pressure).

Brown-Sequard Syndrome
Hemisection, rare.
Pure: ipsilateral motor loss (corticospinal) and position sense loss (posterior column), contralateral dissociated sensory loss one or two levels lower (spinothalamics).
Unless by direct penetrating trauma recovery is seen.

Morphology

Descriptive classification.
Fractures, #-dislocations, spinal cord injury w/out radiographic abnormality (SCIWORA).
- each may be stable or unstable.
- deciding this is not always simple
Consider all x-ray evident and all neurologically injured pts to be unstable until consultation.
D E A B M I M

MANIFESTATIONS

Depends on above classification and specific type of injury.

Cervical Spinal injuries
See C-spine card.

Thoracic Spine #s (T1-T10)

Ant. Wedge Compressions
Axial loading with flexion.
Rarely >25% wedged.
Mostly stable due to rigidity of the rib cage.

Burst Injuries
True vertical axial compression.

Chance Fractures
See below.

Fracture-Dislocations
Relatively uncommon.
Commonly causes deficits - canal is narrow here.

Thoracolumbar Jx #s
High incidence at this site - relative immobility of thoracic vs lumbar spine.
Combo of acute hyperflexion & rotation.
- eg fall from a height, restrained drivers.
Usually unstable.
Deficits common:
- bladder and bowel, lower limb.
Treat all pts with altered CGS, multisystem injury, palpable gap / tenderness in TL-spine with spinal protection until Ap & lat XRd.
- particularly vulnerable to log-rolling.

Lumbar #s
Similar to thoracolumbar #s
- but less neurologic deficits

Chance #s
Distraction applied in flexion, eg a seat belt.
Splitting injury, begins posteriorly, proceeds through vertebral body or disk.
Possibly associated with retroperitoneal / abdo visceral injuries.

D E A B M I M

INVESTIGATIONS

See C-spine card.

Thoracic/Lumbar
AP XR is standard.
- better definition than lateral.
Subsequent films as required.
CT is useful for bony detail.
- very useful for assessing degree of canal compromise.
AP, lateral and CT through suspect areas detects >99% of unstable injuries.

Assessing the T/L-Spine

See notes on XR assessment
D E A B M I M

MANAGEMENT

Introduction
Excessive manipulation and inadequate immobilisation can cause additional neurological injury.
-5% of pts experience worsening of symptoms after reaching the ED due to ischaemia or oedema and failure to immobilise properly.
Protect the spine - then proper evaluation and exclusion of injury may be safely deferred. Need immobilisation above and below the suspected injury site.

Immobilisation
Do not try to reduce an obvious deformity.
Bring to neutral position and maintain.
- however attempts to align the spine for immobilisation on a backboard are not recommended if they cause pain.
Semirigid collars do not assure complete stabilisation of c-spine.
C-spine injury requires: continous immobilisation, semirigid cervical collar, backboard, tape and straps.
- maintain neck in neutral position if intubation likely.
Long spine boards are prefered.
Agitated pts can be difficult
- seek the cause
- if sedation is required, use short acting reversible agents and be an experienced clinician.
Be ever alert for chance of decubitus injury.
- log-roll as part of secondary survey, the board is often removed at this stage.
- if not feasible to remove spine board as quickly as possible log-roll every 2 hrs to reduce risk of ulcers.
- occiput and sacrum esp at risk.

Management Guideline
1) Neurology (eg paraplegia, level of sensory loss) is presumptive evidence of spine injury
2) If awake, alert and non-tender along entire spine - inspection and palpation virtually excludes injury.
- XRs may not be necessary
3) If decreased consciousness, intoxication or spine pain / tenderness:
- AP&lat of entire spin with
- if XR inconclusive spine must remain immobilised while axial 3mm CT performed on suspicious areas.
- then protection may be discontinued.
- note also the danger of prolonged immobilisation on a spinal board.
4) Consult if spine injury suspected / detected.

IV Fluids
Remember pts in hypovolaemic shock will be tachycardic.
Those in neurogenic shock will be bradycardic / normal HR.
If BP does not improve with fluid challenge, judicious vasopressors indicated.
- penylephrine hydrochloride, dopamine and norepinephrine recommended.
Overzealous fluids will cause pulmonary oedema in spinal pts.
Insert a catheter.

Meds
Methylprednisolone is given in Nth America.
30mg/kg in first 15mins.
Then 5.4 mg/kg/hr for next 23 hrs.
If administered in first 3 hrs of injury, infusion should be given for 24hrs.
No benefit from this or other steroid if started at >8hrs.

Transfer
ASAP to definitive care after discussing with relevant specialist.
Be prepared for respiratory care if injury above C6.

D E A B M I M

REFERENCES
ATLS

Jerome Notes

Unstable Cx spine (Spinal Cord)

· 1.5 – 3% trauma

Risk factors

· Age

· Pre-existing neck injury

· Fall

· MVA

· Pedestrian

· Immersion

v 10% incidence

· Head 1st falls ³ 1-1.5 m

· High speed MVA

· Faciomaxillary injuries

Unstable

· Derangement of 2/3 columns

· Neurological risk

· Requires stabilisation

— External

— Internal

· Flexion posterior instability

· Extension anterior instability

Mechanism of injury

· Hyperflexion

· Hyperextension

· Flexion / rotation

· Vertical compression

· Lateral flexion

· Primary spinal cord injury: occurs at the time of injury

· Secondary spinal cord injury: Occurs due to hypoxia (loss airway, failure of ventilation), hypoperfusion (neurogenic shock and haemorrhage), oedema and mechanical disturbance (failure of immobilization).

Resuscitative priorities

· A: airway control maintaining C-spine in-line immobilization

B: High cervical injuries (above C3-C5) compromising phrenic and interocostal function leading to ventilatory failure.

· C: cervical and high thoracic injuries lead to neurogenic shock. Treated with judicious fluids and use of pressors (phenylyephrine) and atropine (overcome bradycardia).

· A thoracic dissection can mimic spinal cord injury as cord ischaemia occurs at the watershed area at T4 between the vertebral and radical aortic branches.

Radiology

· C-spine film – should consist of AP/LAT/Odontiod. The C7/T1 junction should be visualized during the cross-table C-spine.

· It is rare to miss significant injuries in an adequately performed and interpreted set of plain x-rays.

· Neurological signs and symptoms in the setting of a cervical spine injury warrant further evaluation (SCIWORA)

30% in pediatric with spinal cord injury

5% in adult with spinal cord injury

Pre-existing cervical stenosis or hyperflexion or hyperextension injury may result in spinal cord injury without radiological evidence

· Patients without neurological deficit, who are not intoxicated have no distracting injury, are alert and non-confused have no neck or midline pain or tenderness have a 99.8% probability of no cervical spine injury and require no X-rays.

Lateral view:

Pre-vertebral soft tissue space should be

1/3 of the width of C3

equal to the width of C6 at that level

(rule: C2-7 and C7-11).

Back of C1 arch to front of odontiod peg <3mm.

Alignment of

anterior/posterior vertebrate bones,

spinous processes

equal intervertebral disc heights

Anterior view:

Facet joint alignment, evaluate each vertebral body for fracture. If vertebra are offset <1/2 width unilateral facet joint dislocation, >1/2 offest indicates bilateral facet joint dislocation.

Peg view:

Lateral margin of C1 should not overlap C2 (if it does think of Jefferson # - burst # C1). If the total overhang of the lateral masses of C1 on C2 exceeds 7mm think that there may also be a disruption of the transverse ligament.

— Alignment

— Bone

— Cartilage

— Soft tissue swelling

C2-C5 £ 5mm

In alert patients with normal plain films and persistent symptoms – supervised flexion and extension views can be taken or CT/MRI performed.

· Special views

· CT – more sensitive than plain x-ray and can be done without moving the patient. They are indicated if:

— C1-3 – Not properly visualized

— C7 / T1 - Not properly visualized

— Abnormal XR

— Coma / intubated

— Neurology

— Persistent pain

· SCIWORA (Spinal Cord Injury WithOut Radiological Abnormality) – signs or symptoms of spinal cord injury without radiographic abnormality. First described in children, but probably less common in adults. It occurs in about 40% of spinal cord injuries in children <9years and <5% of spinal cord injuries in adults.

· The main value of MRI is in patients with a negative CT who are still suspected of having a traumatic spinal cord injury from ligament disruption, disc protrusion or epidural haematoma. Limitations – cannot be easily used with metallic implants or when intensive monitoring is required.

· Spinal shock differentiate from neurogenic shock associated with spinal cord injury

· Spinal shock is a transient absence of all cord functions below the level of injury

· Neurogenic shock is a hypotension secondary to cervical or upper thoracic complete spinal cord injury

Treatment with both A and B vaso-pressers to improve BP

· For patients with fracture dislocations – closed reduction in emergency room is safe and effective with improved neurological outcome in the presence of spinal cord injury and may decrease the incidence and severity of pulmonary insufficiency.

· Gardner-Wells head tongs can be used to achieve closed reduction of cervical fracture dislocations.

· This is performed under controlled conditions with fluoroscopy, monitoring of vital signs and neurological examination.

· There is a sequential increase in the weights applied to the head tongs until reduction is achieved.

· An initial weight of 10 ponds is applied and weight is increased in 5 pound increments and a lateral x-ray taken until reduction is achieved.

· Contra-indications: skull fracture where pins of tongs are to be applied and distractive type injuries.

· Definitive stabilization is required in the post-injury phase.

Indication for Acute Surgery:

1. Complete spinal cord injuries < 24 hours – restoration of spinal cord anatomy will not improve function after 24 hours thus is not performed.

· Patients with complete injuries > 24 hours old or clinically unstable patients should not undergo surgery. <2% will recover

2. Spinal instability can be treated for early mobilization and Rehabilitation

3. Patients with incomplete injuries and those with neurological deterioration may undergo acute surgery

4. Incomplete spinal cord injuries – there is some sensory or motor function below the level of injury (>75% may recover)

· Restoration of anatomy and decompression of the cord may improve function

· Patterns of incomplete injury: anterior cord syndrome, hemi-section, central cord syndrome

· Incomplete injuries believed to be stable or unstable only in one column can be managed by immobilization only (halo brace cervical spine and molded orthosis for T and L spine) unless neurological deterioration occurs.

· Injuries affecting two or more columns are treated with internal fixation.

What is the bulbocavernosus reflex?

· Monitoring anal sphincter tone in response to squeezing the glans penis or tugging on urinary catheter.

· Lack of motor or sensory function after the reflex has returned indicates complete spinal cord injury

Special Type of Spinal fractures:

Jefferson’s Fracture(C1):

burst # of C1

Odontoid Fracture (C2):

Type I occur in the dens

Type II occurs across the base of dens where it joins the body of C2

Type III occurs extension into the body of C2

Hangman’s Fracture(C2):

bilateral # through the pedicles of C2 causing by hyper-extension (i.e. judicial hanging)

Often associated with neurological deficit

Chance’s Fracture:

hyperflexion injury common in T12-L2 as the Seat-belt injury. Compression # in anterior column then extending to posterior aspect of vertebrate body

Often associated with intra-abdominal injury

Special Type of Neurological Deficit

Complete Transverse Myelopathy:

All function below the injury is lost from transaction, contusion, or stretching of cord.

Anterior Cord Syndrome

Anterior 2/3 of cord (distribution of anterior spinal artery). Motor/pain/temperature gone

light tough/proprioception intact

Central Cord Syndrome

Injury in central spinal cord

Common in pt with pre-existing spinal problem

Motor deficit worse than sensory deficit

Upper extremities deficit worse than lower extremities

Brown-Sequard Syndrome

Common in penetrating injury than blunt

Injury to half of spinal cord

Unilateral disc herniation or unilateral lacerating half cord

Ipsilateral : motor/touch/proprioception gone(tract cross in brainstem)

Contralateral: pain/temperature gone (tract cross in the near cord innervations)

Thoracic Aortic Dissection

T4 is the watershed zone for vertebrate arterial and aortic radicular artery.

Steroid:

- NASCIS II and III National acute spinal cord injury study

- Controversial area: outcome (return of neuro function is no difference and pt LOS is quicker in treated group)

- No value after 8 hours of injury

- Needs prednisone 30mg/kg loading dose (2100mg for 70kg) then 5.4mg/kg/hr for 23 hours (40mg/hr).

- If treated within 3 hours of injury, no further dosage requirement.

- If treated 3-8 hours of injury, may improve outcome if extending treatment to 48 hrs