Spinal cord injuries

FADHIL M. KALOKOLADAVID B. MBANYE PHILEMON RAHAEL

(MD5)

Outlines

IntroductionAetiology & EpidemiologyMechanism of injuryclassificationNeurological evaluationWork upManagementComplications

31 pairs of spinal nerves:8 cervical12 thoracic5 lumbar5 sacral1 coccygeal

Spinal cord:Extends from medulla oblongata – L1

Lower part tapered to form conus medullaris

Enclosed within 33 vertebrae

Anatomy :

On the surface :Deep anterior median fissure Shallower posterior median sulcus

Spinal cord segment :Section of the cord from which a pair of

spinal nerves are given off

Dorsal root – sensory fibres

Ventral root – motor fibres

Dorsal and ventral roots join at intervertebral foramen to form the spinal nerve

Physiology and functionGrey matter – sensory and motor nerve cells

White matter – spinal tracts - Ascending, descending and intersegmental

tracts

Tracts :

Posterior column and lateral corticospinal tract crosses over at medulla oblongata

Spinothalamic tract crosses in the spinal cord and ascends on the opposite side

NB Understanding this helps to reveal the

clinical features of injury patterns and the neurological deficit

Dermatomes Area of skin innervated by sensory axons

within a particular segmental nerve root

Knowledge is essential in determining level of injury

Useful in assessing improvement or deterioration

Downloaded from: Rosen's Emergency Medicine (on 29 April 2009 06:34 PM)

© 2007 Elsevier

Myotomes : Segmental nerve root innervating a muscleAgain important in determining level of injury

Upper limbs:C5 - Deltoid

C 6 - Wrist extensors

C 7 - Elbow extensors

C 8 - Long finger flexors

T 1 - Small hand muscles

Lower Limbs : L2 - Hip flexors

L3,4 - Knee extensors

L4,5 – S1 - Kneeflexion

L5 - Ankle dorsiflexion

S1 - Ankle plantar flexion

Definition

Insult to spinal cord resulting in a change, in the normal motor, sensory or autonomic function.

This change is either temporary or permanent.

Terminologies Plegia = complete lesionParesis = some muscle strength is preservedTetraplegia (or quadriplegia)

Injury of the cervical spinal cordPatient can usually still move his arms using the segments

above the injury (e.g., in a C7 injury, the patient can still flex his forearms, using the C5 segment)

Paraplegia – paralysis of both LL Injury of the thoracic or lumbo-sacral cord, or cauda equina

HemiplegiaParalysis of one half of the bodyUsually in brain injuries (e.g., stroke)

Monoplegia is a paralysis of one limb only.Diplegia is a paralysis of two corresponding limbs (i.e.,

arms or legs).

Causes of SCI

CAUSES

MVAFalls Violence Sports injuries Gunshot InjuriesDiving accidents Blunt Assault Stab Wounds Sport Injuries

55% cases occur in 16 – 30yrs of age> 80% are male!

Other causes:

Vascular disordersTumoursInfectious conditionsSpondylosisIatrogenicVertebral fractures secondary to

osteoporosis Development disorders

Mechanisms:

i) Direct traumaii) Compression by bone fragments /

haematoma / disc materialiii) Ischemia from damage / impingement on

the spinal arteries

Patterns of injury

Fracture

Dislocation

Fracture dislocation

SCIWORA

SCI - Classification

ASIA – American Spinal Injury Association

Based on neurological responses, touch & pinprick sensation (dermatome), +muscle strength.

A – Complete: no sensory or motor function preserved in sacral segments S4 – S5

B – Incomplete: sensory, but no motor function in sacral segments

C – Incomplete: motor function preserved below level and power graded < 3

D – Incomplete: motor function preserved below level and power graded 3 or more

E – Normal: sensory and motor function normal

Can be1) Complete 2) Incomplete

Complete: i) Loss of voluntary movement of parts

innervated by segment, this is irreversibleii) Loss of sensationiii) Spinal shock

Incomplete:

i) Some function is present below site of injury

ii) More favourable prognosis overalliii) Are recognisable patterns of injury,

although they are rarely pure and variations occur

Incomplete injury syndromes

i) Central Cord Syndrome

ii) Anterior Cord Syndrome

iii) Posterior Cord Syndrome

iv) Brown – Sequard Syndrome

v) Cauda Equina Syndrome

i) Central Cord Syndrome : Typically in older patients Hyperextension injury Compression of the cord anteriorly by

osteophytes and posteriorly by ligamentum flavum

Also associated with fracture dislocation and compression fractures

More centrally situated cervical tracts tend to be more involved hence flaccid weakness of arms > legs

Perianal sensation & some lower extremity movement and sensation may be preserved

ii) Anterior cord Syndrome: Due to flexion / rotationAnterior dislocation / compression fracture of

a vertebral body encroaching the ventral canal

Corticospinal and spinothalamic tracts are damaged either by direct trauma or ischemia of blood supply (anterior spinal arteries)

Clinically: Loss of powerDecrease in pain and sensation below lesionDorsal columns remain intact

ii) Posterior Cord Syndrome: Hyperextension injuries with fractures of

the posterior elements of the vertebrae

Clinically: Proprioception affected – ataxia and

faltering gait Usually good power and sensation

Brown-Sequard syndrome

v) Cauda Equina Syndrome: Due to bony compression or disc

protrusions in lumbar or sacral region

Clinically Non specific symptoms – back pain

- bowel and bladder dysfunction- leg numbness and weakness

Spinal Shock

Transient reflex depression of cord function

below level of injuryInitially hypertension due to release of

catecholaminesFollowed by hypotensionFlaccid paralysis Bowel and bladder involvedSometimes priaprism develops Symptoms last several hours to days

AsessmentSpinal shock

Bulbocavernosus reflex

Complete VS incomplete cord injury spinal shock Sacral sparing

Voluntary anal sphincter control Toe flexor Perianal sensation Anal wink reflex

Neurogenic shock:

Triad of - i) hypotensionii) bradycardia iii) hypothermia

More commonly in injuries above T6

Secondary to disruption of sympathetic outflow from T1 – L2

Loss of vasomotor tone – pooling of bloodLoss of cardiac sympathetic tone –

bradycardia Blood pressure will not be restored by

fluid infusion aloneMassive fluid administration may lead to

overload and pulmonary edema Vasopressors may be indicated

Autonomic dysreflexia (AD)

A syndrome of massive imbalanced reflex sympathetic discharge

Occurring in patients with spinal cord injury (SCI) 48-90% in patients with SCI above T6 Above the splanchnic sympathetic outflow (T5-T6).

Primarily a male phenomenon; M:F=4:1

About 66% in females in labour

Pathophysiology

Occurs after the phase of spinal shock in which reflexes return.

Below the injury, intact peripheral sensory nerves transmit impulses

That ascend in the spinothalamic and posterior columns

Stimulate sympathetic neurons located in the intermediolateral gray matter of the spinal cord.

Inhibitory outflow above the SCI from vasomotor centres is increased,

Unable to pass below the block of the SCI.

Release of various neurotransmitters (dopamine-b-hydroxylase, norepinephrine, dopamine),

Causing piloerection, skin pallor, and severe vasoconstriction in arterial vasculature.

Sudden elevation in blood pressure + vasodilatation above the level of injury.

Headache caused by vasodilation of pain sensitive intracranial vessels.

Increase in parasympathetic vagal tone by Vassomotor centers compensatory bradycardia.

Parasympathetic nerves prevail above the level of injury sweating and vasodilatation with skin flushing.

Clinically

Headaches, and a sense of anxiety

sudden rise in both systolic and diastolic blood pressures, usually with bradycardia

profuse sweating above the level of lesion,

flushing of the skin

nasal congestion is common.

Neurological evaluationMotor: how to test each segment?

Sensory: how to determine the level?

Spinal assessment

Palpate entire spine

DeformityGrating / crepitus

TendernessGapping interspinous spaces

BogginessLacerations

DRE, perineal sensation + tone

Imaging modalitiesCT scanMRIX-ray - standard trauma series is composed of 5 x-ray

views: cross-table lateral, swimmer's, oblique, odontoid, Anteroposterior

Radiographic level = the level of fracture on plain XRays / CT scan / MRINB: spine level does not correspond to spinal cord

level below the cervical region

Radiolographic evaluation X-ray Guidelines (cervical)

AABBCDS

Adequacy, Alignment Bone abnormality, Base of skull Cartilage Disc space Soft tissue

Alignment• The anterior vertebral line, posterior vertebral line, and spinolaminar line should have a smooth curve with no steps or discontinuities

• Malalignment of the posterior vertebral bodies is more significant than that anteriorly, which may be due to rotation

• A step-off of >3.5mm issignificant anywhere

Bones

Disc

Disc SpacesShould be

uniform Assess spaces

between the spinous processes

AP C-spine Films

Spinous processes should line up

Disc space should be uniform

Vertebral body height should be uniform. Check for oblique fractures.

Swimmer’s view

Open mouth view

Adequacy: all of : all of the dens and the dens and lateral borders of lateral borders of C1 & C2C1 & C2

Alignment: lateral : lateral masses of C1 and masses of C1 and C2C2

Bone: Inspect dens for lucent fracture lines

Management

Management….

Advance Trauma Life Support (ATLS) guidelines

Primary survey; ABCDE -Adequate airway and ventilation are the most

important factorsSupplemental oxygenationEarly intubation is critical to limit secondary

injury from hypoxia

Secondary surveys (e.g. Hx)

Initial Management

Immobilization

Entire spine until when the x-ray are available

Supine, no rotation no bending

It protect further damage -Beware of decubitus ulcers

Methods of immobilization

Rigid collar (Philadelphia hard collar)>>>

Sandbags and straps

Spine board

Braces

Log-roll to turn

LogrollingAt least 4 people

1 Maintain inline manual immobilization 1 For the torso (trunk) 1 For the pelvis and legs 1 To direct the move

Move the pt towards the attendants as a unit

Maintain neutral position of the spine

Children have proportionally large heads

IV fluidsPersistent hypotension after 2 liters neurogenic

shockUse of vasopressors Dopamine / AdrenalinInvasive monitoring; CVP and urethral catheters

SteroidsMethylprednisolone - 30mg/kg in the first 15minThen 5.4mg/kg/hr for 24-48hrs

Exclusion criteria Cauda equina syndrome Pregnancy Age <13 years Patient on maintenance steroids

Mnx … cont

NGT Prevents aspirationDecompresses the abdomen (paralytic ileus is common

in the first days)

Foley catheterUrinary retention is common andFor monitoring

- Spinal assessment

Care of paraplegics

Skin careBowel and bladderPsychological supportWheelchair rehabilitation

Surgical Mnx

Indications for surgeryInstability

maintaining alignment to allow development of solid bone fusion;

preventing progression of deformity;

alleviating pain

progressive neurological deficit???? For early rehabilitation????

complications HypotensionNeurogenic painSpinal shockhypothermiaparaplegiaSexually dysfunction Bladder + bowel

dysfunction -Incontinence -paralytic ileus -urinary problems

(UTI)

Weight loss or gainDepressionAutonomic dysreflexiaPressure sores (bed

sores)Pneumonia and

asthmaCVS diseasesSpasmsyringomyeliaDeep vein thrombosis -pulmonary embolism

References:

1. ATLS, et al. Student Course Manual. 7th Edition 2004;7:177-204

2. Keith L Moore et al. Clinically Orientated Anatomy. 3rd Edition1992;4:359

3. Snell.Clinical.Neuroanatomy.7th.20094. Essential of Orthopedics