pediatric c-spine injury joshua rocker, md schneider children’s hospital lij medical center
TRANSCRIPT
Pediatric C-Spine Injury
Joshua Rocker, MD
Schneider Children’s Hospital
LIJ Medical Center
• Anatomical Considerations• Embryology• Risk Factors• Causes of Injury• Immobilization• Symptoms and Physical Exam• Radiography• Prediction Rules
Anatomical Considerations
Children <8 years old
• Relatively larger heads than body– Head circumference 50% adult by 2 yrs
vs chest circumference, 8 yrs
Children <8 years old
• Cervical spine fulcrum– Moves caudally
• C2-C3 at birth• C5-6 at 8 yr and older
Children <8 years old
• Weaker cervical musculature and increased laxity of ligaments
• Immature vertebral joints
• Horizontally inclined articulating facets
– Facilitate sliding of upper c-spine
Children’s C-spine Injuries
• More susceptible to:– fractures through growth plates – ligamentous injuries
• Why– Growth centers fragile to sheer forces
during rapid decel or flex/ext
(particularly at the synchondrosis b/n odontoid and body of C2)
SCIWORA
• “Spinal Cord Injury without Radiological Abnormality”– Theoretical increase risk in children– Young spinal column more elastic than
spinal cord- can handle more distraction before rupture
• 5cm vs 5-6mm
Children 8yrs and older
• Equivalent to adult
• Most injuries to vertebral bodies and arch
• Lower C-spine
Embryology and why pediatric C-spines are
difficult to interpret
Embryological Considerations
• C1 (Atlas) formed by 3 ossification sites– Anterior arch and 2 neural arches
Embryology: C1
• Anterior arch fuses with neural arches by 7 yrs. Before this non-fusion can be mistaken as fracture
Embryology: C2
• C2 (Axis) has four ossification centers– 2 neural arches– 1 for the body– 1 odontoid
Embryology: C2
• Body fuses with dens at 3-6 yrs
• The fusion line or remnant of cartilagenous synchondrosis can be seen till 11 yrs
Embryology: C3-C7
• Same developmental pattern
• 3 ossification centers
• Neural arches fuse posteriorly 2-3 yrs
• Body fuses with arches 3-6 yrs
Embryology
• Coronal view: Notice synchondroses
Predisposing risk factors
Congenital abnormalities
• Downs Syndrome– 15% with atlantoaxial instability
Congenital abnormalities
• Klippel-Feil– Fusion of cervical vertebrae
Congenital abnormalities• Morquio (MPS IV)
– No galctose 6-sulfatase– Hypoplasia of odontoid
Congenital abnormalities
• Larsen’s Syndrome– skeletal dysplasia with multiple joint
dislocations, short stature, abnormal facial features
At Risk by History
• Spinal Cord surgery
• C-spine arthritis
Causes of Injuries
Causes of Injuries: By age
• Infants– Birth Trauma
• 1-8 yrs– MVAs and falls
• > 8 yrs – Sports Injuries and MVAs
Causes of Injuries:
• Direct severe force to neck
• Diving
• Acceleration-deceleration
Causes of Injuries: Mechanism
• Hyperflexion
• Hyperextension
• Axial Load
• Roatational
• Blow to Chin
Causes of Injuries:Hyperflexion
• Most common
• Cause wedge fracture of anterior vertebral bodies
• Disruption of posterior elements
• Ex: – Clay-shoveler’s, – anterior teardrop fracture
Hyperflexion: Clay-shoveler’s
Hyperflexion: Teardrop fracture of anteroinferior portion of vertebral body
Causes of Injuries: Hyperextension
• Compression of posterior elements
• Disruption of anterior longitudinal ligament
• Ex: – Hangman’s
Hyperextension: Hangman’s Fracture
Causes of injuries: Axial Load
• Direct load on top of head
• May cause burst or comminuted fracture of C1.
• May also cause injury caudal to C-spine
• Ex:– Jefferson fracture
Axial Load: Jefferson fracture
•
Causes of Injuries
• Rotational– Usually associated with additional injuries
• Chin Trauma– Fractures of posterior teeth and mandibular
condyles seen as a single injury pattern
Immobilization
Indications
• Mechanism– Severe force– Diving– Accel-dec
• PE– AMS– Neuro deficits– Multi-system trauma– Neck pain/tenderness– Distracting injuries
Ouch!!!!
• 3-25% of patients with SC injury develop neurological deficits caused by manipulation during resuscitation or transport
Immobilize
• Neck- in collar– Stif-Neck– Philadelphia– ProSplint
• Body- on long backboard
Neutral Position
• Not well defined– “anatomical position of the head and torso
that one assumes when standing and looking straight ahead”
– External auditory meatus is in line with the shoulder in the coronal plane
– “Supine without rotating or bending the spinal column” ATLS
Neutral Position
• Adults (>8 yrs)– Require occiput elevation (1.3-9.5, 2cm)
• Children– Special allowance b/c relatively large
heads• Special peds boards with depressed area for
head• Elevate back with padding (2.5cm)
Protocols
• Do not reduce obvious deformities
• Keep helmets in place unless need airway
• Log roll onto board with support of head/neck and torso
• Place wedges beside head to limit lateral movement
Protocols: Airway
• Jaw-thrust maneuver with in-line traction
Protocol: Surgical Airway
• Nasotracheal intubation– Contraindicated: apnea, facial injuries (?fx
of cribiform plate)
• Orotracheal intubation with in-line stabilization
• Surgical airway– Maxillofacial or laryngotracheal trauma
Symptoms and Physical Exam
Symptoms
• Classic Triad– Local pain, muscle spasm and decreased
ROM
• Transient or persistent parasthesias or weakness– SCIWORA
Symptoms
• “Burning hands”– Seen with football players– Transient burning in hands/fingers– Hyperextension of C-spine with SC
contusion
• Asymptomatic– Significant mechanism or distracting injury
Physical Exam
• Essentials
– Vital Signs
– Neuro
– Neck
Physical Exam
• Vitals– Apnea or hypoventilation
• Injuries to C3-C5
– Spinal Shock• Hypotension, bradycardia, temperature
instability
Physical Exam
• Neuro exam
– Tone, strength, sensation and reflexes
– Up to 50% of children with C-spine injuries have neuro deficits
Tone
• Loss of spontaneous breathing if injury above C4
• Hypotonia– Lower motor neuron deficit– Spinal shock
Tone
• Rectal tone– Absence- poor prognostic sign– Bulbocavernous reflex (S3-S4)
• Squeezing glans, tapping on mons pubis, pulling on foley
– Stimulate trigone of the bladder reflex contraction of anal sphincter
Strength
• Dorsiflexion of the wrist– C6
• Extension of the elbow– C7
• Extension of the knee– L2-L4
• Dorsiflexion of the great toe– L5
Sensory
• Most common deficit with SC injuries
• Level of sensory impairment localizes level of injury
Reflexes
• Areflexia indicates spinal shock – Usually lasts less than 24 hours
Specific Injuries
• Anterior Cord Syndrome– Hyperflexion and anterior cord
compression– Paralysis and loss of pain WITHOUT loss
of light touch or proprioception
Specific Injuries
• Central Cord Syndrome– Hyperextension Injuries– Weakness greater in upper vs lower
extremities
Specific Injuries
• Brown-Sequard syndrome– Cord Hemisection
– Ipsilateral • Paralysis, Loss of proprioception and light
touch
– Contralateral• Loss of pain and temperature
• Horner’s Syndrome– Disruption of cervical sympathetic chain– Ptosis, miosis and anhidrosis
Specific Inuries
Neck Exam
Maintain in-line stabilization
• Palpate spinous processes
• Assess muscle spasm
• Assess for deformities
Radiography
What to do?
• If your suspicion of injury is high– get CT!!! (>98% sensitive)
• If low to moderate– get 3 view radiographs
• AP, cross table lateral, odontoid (open mouth)
• Lateral view identifies approx. 80-90% of fx, dislocations and subluxations
Plain Radiographs
• Lateral– Must visualize all 7 cervical vertebrae – Include C7-T1 junction
– If difficult visualizing• Gentle traction on arms (?)• Transaxillary (swimmer’s) view
Lateral view: 4 curvilineal contour lines
• Anterior vert body
• Posterior vert body
• Spinolaminar line
• Tips of spinous
processes
•
Psuedosubluxation
• C2 on C3– 20-40% of children
• C3 on C4– 14%
Swischuk line
• line from the anterior
aspect of C1-C3
spinous processes
• anterior C2
spinous process
within 2 mm
Soft tissue spaces
• Prevertebral space/
Retropharngeal– C2- <6mm– C6- <22mm
– C3/C4• <8 yrs < ½-2/3 diameter
of AP vertebral body• >8 yrs < 7mm
Soft tissue spaces
• Predental space – <8 yrs < 4-5mm– >8 yrs < 3mm
• Represents:– Atlantoaxial instability or rotational sublux or Jefferson fx
AP View
• Height of vertebral
bodies similar
• Spinous processess
aligned
Odontoid
• Equal amounts of space
on each side of the dens
• Lateral aspects of C1
should line up with the
lateral aspects of C2
Odontoid fractures
• Types– 1
• Apex of dens
– 2• Base of dens
– 3• Extends into body of C2
Odontoid Fracture types
Flexion-Extension View
• May identify cervical instability, atlantoaxial joint instability or ligamentous injury
• If suspicion still present with negative films
• Adds little to evaluation
Oblique View
• Better visualization of pedicules, facet alignment and posterior lamina or articular mass fractures
• Usually add nothing
Prediction Rules
Prediction Rules
• In alert and stable trauma patients establish rule to avoid irradiating low risk patients
Canadian C-Spine Rule
• Stiell, et al JAMA, 2001• Prospective, but Canadian…• 8924
– Blunt trauma– GCS- 15– Stable vitals
• SCI in 151 (1.7%)– Rule 100% sensitive
Canadian Rule
• High risk– > 65 yrs– Dangerous mechanism
• Fall >1m/5 stairs• Axial load• MVA >100km/hr• Motorized recreational vehicle• Bicycle vs immobile object
– Paresthesias in extremities
Canadian Rule
• Low risk if :– Simple rear end MVA– Sitting position in ER– Ambulatory at scene– No neck pain at scene– Absence of mid-line tenderness
• If low risk…
Voluntarily and actively rotate neck 45 degrees both left and right
• If able- no Xray
Canadian Rule
Canadian Rule
• Validated study
• 8923 enrolled
• 169 with SCI (2%)
• Sensitivity = 99.4%
• Specificity = 45.1%
• But…
Canadian C-Spine Rule
• In adults!!!!!!!!
NEXUS: National Emergency X-Radiography Utilization
Study
• Hoffman, et al, NEJM, 2000
• Prospective
• 34,069 enrolled
• Blunt trauma
NEXUS Rule
• Get radiography unless all are met:– No midline tenderness– Not intoxicated– No AMS– No focal neuro deficits– No distracting injuries
NEXUS Rule
• SCI- 818 (2.4%)
• Sensitivity = 99.6%
• Specificity = 12.9%
Comparing Canadian and NEXUS
• Canadian rule more sensitive and more specific
• Neither have been validated in settings other than where they were established
NEXUS- Children
• Viccellio, et al, Pediatrics, 2001
• NEXUS data, extract pediatric info
• 3065 pts (9% of total)– <18 yrs
• SCI- 30 (0.98%)
Viccellio, et al
• SCIWORA- 0%
• SCI– Only 4/30= 13.3% were younger then 9 yrs
(said population made up 29.5% of total)– 0/30= 0% younger than 2 yrs (2.9% of
total)
Viccellio, et al
• NEXUS decision rule 100% sensitive
• Low risk- 603 of 3065– Reduction of Xrays in 19.7%
Viccellio, et al
• Conclusion:– NEXUS is sensitive for peds– Need a prospective study of 80,000 cases
to improve CI and even more for youngest peds
– Can only be generalized for the adolescent population
– SCIWORA more common in adults
Viccellio, et al
• Discussion:– Rarity of SCI in infants
• Doesn’t occur or lethal because of anatomy (damage to higher C-spine)
Jaffe, et al
• Ann Emerg Med, 1987• Retrospective review of 206 children
<16• 8 variables: neck pain, neck
tenderness, limited ROM, hx of trauma to neck, abnl reflexes/sensation or MS.
• 98% sensitive if 1 positive• Avoided radiation in 38%
SO……..
Remember
• Anatomy
• Risk factors
• Mechanism
• Symptoms
• If Radiography– Ossification centers
Thank you!!!
•