Spine and spinal cord trauma Flashcards
Signs of spinal shock
Hypotension
Bradycardia
Signs of high neurologic deficit (eg lack of limb movement)
Other injuries associated with C spine fractures
Brain injury
Another non-contiguous spine fracture in 10% pts
Level of spinal cord injury associated with neurogenic shock
T6 and higher
Mechanism of neurogenic shock
Distributive shock from lack of vasomotor tone
Injury to sympathetic fibres that maintain vascular tone and heart rate
Three spinal cord tracts that can be examined clinically
Dorsal column (gracile fasciculus, cuneate fasciculus )
Lateral corticospinal tract
Spinothalamic tract
Dermatome definition
Area of skin innervated by a particular nerve root
Sensory level definition
The lowest dermatome with normal sensory function
Can differ between sides of the body
How to document spinal cord injury assessment
ASIA worksheet
(American Spinal Injury Association)
Muscle strength grading score 5
Normal strength
Muscle strength grading score 4
Full ROM but less than normal strength
Muscle strength grading score 3
Full ROM against gravity but not against resistance
Muscle strength grading score 2
Full ROM with gravity eliminated
Muscle strength grading score 1
Palpable or visible contraction
Muscle strength grading score 0
Total paralysis
Muscle strength grading score NT
Not testable
Myotome C5
Deltoid abduction
Myotome C6
Biceps flexion
Myotome C7
Triceps extension
Myotome C8
Wrist extension (radial test)
Myotome T1
Finger abduction (ulnar test)
Or
Grip strength
Myotome L2
Hip flexion
Myotome L3 / L4
Knee extension
Myotome L5
Knee flexion
or
Big toe extension
Myotome S2, S3, S4
Anal tone
Neurogenic shock definition
Loss of vasomotor tone and sympathetic innervation to the heart
Causes hypotension and inability to mount tachycardic response
Physiologic effects NOT reversed with fluid resuscitation alone
Spinal shock definition
Loss of muscle tone and reflexes immediately after spinal cord injury
Spasticity
Consequences of spinal injury on other organ systems
Resp failure due to paralysis of respiratory muscles
Inability to perceive pain - masks other serious injuries
Classification of spinal injuries
Level (Bony and neurological)
Severity of neuro deficit
Spinal cord syndromes
Morphology
Bony level classification of spinal injury
Specific vertebral level at which bony damage has occurred
Neurological level classification of spinal injury
The most caudal segment of spinal cord with:
- Normal sensory function
AND
- Motor function with muscle strength 3 or above
Severity of neurological deficit classification of spinal injury
Paraplegia
Quadriplegia / Tetraplegia:
- Complete
- Incomplete
Injuries associated with paraplegia
Thoracic spinal injuries
Injuries associated with Quadriplegia / Tetraplegia
Cervical spinal injuries
Spinal cord syndromes
Central cord syndrome
Anterior cord syndrome
Brown-Sequard syndrome
Central cord syndrome
Disproportionate greater loss of motor strength in upper extremities than lower extremities
Varying sensory loss
Anterior cord syndrome
Injury to motor and sensory pathways in anterior cord
Paraplegia and loss of pain / temperature sensation
Brown-Sequard syndrome
(Often penetrating) injury to one side of the spinal cord
Ipsilateral motor loss and loss of proprioception
Contralateral loss of pain / temperature sensation 1 or 2 levels below injury level
Morphology classification of spinal injuries
Fractures
Fracture-dislocations
SCIWORA
Penetrating injuries
All of above can be described as stable or unstable
SCIWORA
Spinal Cord Injury Without Radiological Abnormalities
C spine fracture mechanisms
Axial
Flexion
Extension
Rotation
Lateral bending
Distraction
Most common level of C spine fracture
C5
Most common level of C spine subluxation
C5 on C6
Types of thoracic spine fractures
Anterior wedge compression
Burst
Chance fractures
Fracture-dislocations
Mechanism of anterior wedge compression fractures
Axial loading with flexion
Mechanism of burst fractures
Vertical axial compression
Mechanism of Chance fractures
Flexion about an axis anterior to the vertebral column
Eg lap seat belts
Can be associated with abdo visceral / retroperitoneal injuries
Mechanism of fracture-dislocations of the thoracic spine
Extreme flexion
OR
Severe blunt trauma to spine
Level of Thoracolumbar junction
T11 through to L1
Mechanism of Thoracolumbar junction fractures
Acute hyperflexion + rotation
Considerations with Thoracolumbar junction fractures
Usually unstable
Highly vulnerable to rotational movement - careful with logroll
Types of lumbar spine fractures
Similar to thoracic spine fractures
Spinal injuries associated with blunt carotid and vertebral artery injury
C1-C3 fractures
C spine fracture with subluxation
Fractures involving foramen transversarium
Potential complication of blunt carotid and vertebral artery injury
Stroke
Indication for MRI C spine
Neurological deficit but no radiographic evidence of fracture
Look for soft tissue compressive lesions, contusions or ligamentous injury
Spinal immobilisation method
Lay patient on firm surface
Rigid cervical collar
Head blocks
When to suspect neurogenic shock
Persistent hypotension
Bradycardia
No active haemorrhage
Management of neurogenic shock
Avoid overzealous IV fluid
Consider vasopressors