Spinal Injuries

Question 1

Mechanisms of Injury

Answer 1

1) Penetrating Injury (gunshot, knife wound etc.)

2) Blunt Injury - most common, involves number of forces that occur in combination

Question 2

Types of Blunt Injury

Answer 2

1) Forced flexion (anterior) or flexion with rotation
2) Forced extension (hyperextension)
3) Vertical compression (axial loading)

Question 3

The most mobile regions of the spine are

Answer 3

Cervical and the thoracolumbar junction

Are also most common sites of injury

Question 4

Types of Vertebral Fracture /(7)

Answer 4

Simple
Compression or Wedge
Communicated or Burst Fracture
Teardrop
Dislocation
Subluxation
Fracture Dislocation

Question 5

Simple Fracture

Answer 5

Generally involves elements of the neural arch (spinous or transverse process)

Question 6

Compression or Wedge

Answer 6

Anterior compression to the vertebral body

Question 7

Communicated or Burst

Answer 7

Shattering injury to vertebral body
Likelihood of fragments impinging on spinal cord
Resultant severe damage

Question 8

Teardrop

Answer 8

Small fragment chipped away from vertebral body
Free to lodge in the spinal canal

Associated with posterior dislocation of the vertebral body
Neurological deficit
Removal of bone fragment if in canal

Question 9

Subluxation

Answer 9

Partial or incomplete dislocation of one vertebral over another

Question 10

Fracture Dislocation

Answer 10

Fracture or dislocation with ligament and cord injury

Question 11

Unstable Spinal Injury

Answer 11

Vertebral and ligamentous structures are not able to support or protect the injured spine

Moment may increase pressure on spinal cord and further neurological deficit

Question 12

Stable Spinal Injury

Answer 12

Bony and/or ligamentous structures support the injured area sufficiently to prevent progression of the neurological deficit and prevent bony deformity

If posterior elements (ligament between neural arch and the articulating facet joints) survive the injury, it is considered stable

Question 13

Stability Classification system (Column Concept)

Answer 13

Anterior, Middle and Posterior Columns

Question 14

Anterior Column

Answer 14

Anterior Longitudinal ligament and anterior 2/3 vertebral body and intervertebral disc

Question 15

Middle Column

Answer 15

Posterior Longitudinal ligament, posterior 1/3 of the intervertebral disc and posterior wall of the the vertebral body

Question 16

Posterior Column

Answer 16

Neural arch (lamina, pedicles, and ligamentum flavum), the articular processes and facet joint capsules, the spinous processes and the interspinal ligaments

Question 17

4 Major Categories of Spinal injuries

Answer 17

Forward flexion (anterior compression fractures)

Flexion- axial compression (burst)

Flexion- distraction injuries (seat belt injuries and chance fractures)

Fracture-dislocation (sheer injuries that cause sagittal or coronal plane translation)

Question 18

Spinal Injuries with disruption of all 3 columns

Answer 18

are considered to be unstable

Question 19

C1 Fractures/ Atlas/ Jefferson Fractures

Answer 19

Axial loading through top of the head

Most common cause of disruption of the ring of the C1 vertebra

Question 20

C2 Fractures / Axis

Answer 20

Most commonly, odontoid process or posterior element damage

Flexion typically the mechanism

Hangman’s fracture is through posterior elements, caused by forced hyper extension

Question 21

Are C1, C2 fractures commonly associated with neurological deficit?

Answer 21

No

Question 22

Common Injuries to Sub Axial Cervical Spine (C3-C7)

Answer 22

Most commonly axial load flexion fractures with burst type of injury

OR

Flexion distraction with uni or bilateral locking of the facet joint depending on amount of rotation that occured

Subluxation and relocation without fracture may result in neurological deficit without visual damage, this is more commonly caused by hyperextension injury

Question 23

Common Injuries to the Thoracic Spine

Answer 23

Usually a fracture or fracture dislocation

Various mechanisms, but most commonly axial loading and flexion with rotation

Anterior compression results in varying degree of posterior protrusion or kyphosis

Question 24

Thoracolumbar Junction

Answer 24

Susceptible area for spinal injury

Area of stress and increased mobility below rigid rib cage

Associated with flexion and rotational forces with resultant conus and/or cauda equina lesion

A fall will often result in a compression fracture

Question 25

Lumbar and Sacral

Answer 25

Fractures within these regions resemble those of the thoracolumbar junction

Question 26

Chance Fractures

Answer 26

Lap belt injury unique to lumbar spine (most commonly L1, L2) Caused by severe flexion and rotation around a fixed axis (pelvis secured by belt) Leads to bony and ligamentous disruption to the lumbar spine Anterior compression to vertebral body Transverse fracture through posterior elements of the vertebrae Associated with internal abdominal injuries

Question 27

Determining Neurological Impairment

Answer 27

Examinations of dermatomes and myotomes together, level of injury may be established, determine what functions remain

Question 28

Insult to spinal cord, several mechanisms cause progressive damage

Answer 28

Related to mechanical insult Biochemical responses Hemodynamic changes, often associated with multiple trauma

Question 29

Primary Pathological changes after injury

Answer 29

Bleeding and swelling at site of injury can cause severe necrosis of gray matter

Question 30

Secondary Pathological changes

Answer 30

Associated Biochemical and hemodynamic changes alter physiological response to injure Changes in systemic blood flow and oxygen tension May cause impaired CNS function/systemic blood loss, damaging delicate structure of spinal cord

Question 31

Quad/tetraplegia

Answer 31

Impairment or loss of motor and/or sensory function in cervical segments of spinal cord due to damage of neural elements within canal ``` Impaired function of arms trunk pelvic organs legs ``` Does not include brachial plexus lesions or injury to peripheral nerves outside the neural canal

Question 32

Paraplegia

Answer 32

Impairment or loss of motor and/or sensory function in the thoracic, lumbar, or sacral segments of the spinal cord Secondary to damage of neural elements within the canal Arm function spared depending on level of injury Trunk, pelvic organs, and legs maybe involved Term used in referring to cauda equina and conus medullaris injuries Does not involve lumbosacral plexus lesions or peripheral nerves outside the canal

Question 33

Complete Transverse Syndrome

Answer 33

Below level of injury there is loss of all motor and sensory nerve transmissions

Question 34

Causes of complete paraplegia or quadraplegia

Answer 34

Complete severence of spinal cord Complete breakage of nerve fibers by stretching of the cord, coverings may still be intact with normal appearance Complete ischemia of the cord, interruption of the total blood supply

Question 35

Incomplete Syndromes

Answer 35

Central Cord Anterior Cord Brown-Sequard Conus and Cauda Equina Injuries

Question 36

Central Cord Syndrome Cause

Answer 36

Damage to central portion of cervical cord Corticospinal tract fibres are organized with arms most central, trunk immediately, and legs laterally

Question 36

Brown - Sequard Syndrome Cause

Answer 36

Damage to one side of the cord only

Question 36

Conus and Cauda Equina Results

Answer 36

Loss of motor function Sensory function not markedly impaired Extremely variable pattern with asymmetrical involvement Roots have some recovery potential, causing outlook to be favorable Lower motor neuron (flaccid) invovlement of bowels, bladder and sexual function because those reflexes are controlled within the conus

Question 36

Central Cord Syndrome Results

Answer 36

Fibres located most centrally are damaged with those more laterally spared Arms affected but legs may not be Some distal nerve transmission is intact

Question 36

Anterior Cord Syndrome Results

Answer 36

Loss of function below injury level to cord portion responsible for voluntary motor pathways and major sensory tract Sparing of posterior column due to alternate blood supply Position, vibration, and touch sense are preserved

Question 36

Conus and Cauda Equina Injuries Cause

Answer 36

Damage to the conus medullaris or spinal nerves forming the cauda equina

Question 37

Anterior Cord Syndrome Cause

Answer 37

Usually caused by damage due to infarction from main artery Resultant blood loss to anterior 2/3 of the cord Posterior cord is unaffected

Question 37

Factors in determining appropriate management of cervical injury

Answer 37

Type of fracture and/or associated dislocation Stability Alignment

Question 38

Cervical Fracture or Fracture/Dislocation requires reduction

Answer 38

Patient put in traction with weights applied to CB tongs or a halo ring Generally 20-30 lbs are used to reduce and maintain the alignment of a fracture Up to 120 lbs can be used to reduce locked facet joints

Question 39

Cervical orthosis provides 3 primary functions

Answer 39

1. Motion restriction to protect or prevent pain 2. Motion restriction to protect spinal instability pre-post surgery 3. Emergency protection - immediately following trauma

Question 40

Spinal mobility

Answer 40

Cervical > Lumbar > Thoracic Thoracic spine possess greater flexion than extension Lateral flexion increases in the caudal direction, while axial rotation decreases

Question 41

Brown- Sequard Results

Answer 41

Ipsilateral loss of function below injury level, ipsilateral motor paralysis Loss of pain and temperature sensation on the contralateral side of the body

Question 42

Biomechanical Principles of Orthotic Design

Answer 42

Balance horizontal forces Fluid compression Distraction Construction of cage around patient Placement of irritant = kinesthetic reminder Skeletal fixation Increase intra-abdominal pressure to decrease vertebral load Restriction of motion: Damage to posterior element, instability increases with flexion Damage to the anterior element, instability increases with extension

Question 43

Surgical Management

Answer 43

Posterior Wiring Anterior decompression Contoured anterior spinal plate

Question 44

Neutral head position

Answer 44

Alignment of patient head with respect to the body is crucial for device success Know neutral head position in the coronal and sagittal plane Be aware that this position may vary with each patient according to pain and comfort