Basics of Spinal Trauma Flashcards
What is a myotome?
Group of muscles that a single spinal nerve root innervates. Nerve levels are associated with certain movements as seen in image attached

What is a dermatome?
An area of skin supplied by a single nerve root

In terms of anatomical columns of the spine, what constitutes the anterior column of the spine?
- Anterior longitudinal ligament
- Anterior annulus
- Anterior 2/3rd’s vertebral body

In terms of anatomical columns of the spine, what constitutes the middle column of the spine?
- Posterior 1/3 of the vertebral body
- Posterior annulus
- Posterior longitudinal ligament

In terms of anatomical columns of the spine, what constitutes the posterior column of the spine?
Everything posterior to the PLL
- Pedicles
- Facet joints and articular processes
- Ligamentum flavum
- Neural arch and interconnecting ligaments
- Spinous Processes

What system is most commonly used to classify thoracolumbar spinal fractures?
McAfee Classification system

What is a wedge compression fracture?
Isolated anterior column compresson

What is the following fracture?

Wedge compression fracture
What is a stable burst fracture?
Anterior and middle column compression, but posterior column is normal

What type of fracture is this?

Burst Fracture - stable
What is an unstable burst fracture?
Anterior and middle column compression, with disrupted posterior column

What is the mechanism of injury of a burst fracture?
High-energy compressive injury (axial loading) - IV disc is rammed into vertebral body
Typically fall from height or motor vehicle accident
What is the mechanism of injury of a flexion distraction fracture?
Axis of flexion: posterior to anterior longitudinal ligament
What is a flexion-distraction fracture?
- Compressive failure of the anterior column while the middle and posterior columns fail in tension
- Tensile failure of the middle column results in tear or attenuation of the posterior longitudinal ligament
- Subluxation, dislocation or fracture of the facets can occur
- Most varieties of this injury are potentially unstable because the ligamentum flavum, interspinous ligament, and supraspinous ligament usually are torn

What type of fracture is the following?

Burst fracture - Unstable
What is a Chance fracture?
- Flexion-distraction type injuries of the spine that extend to involve all three spinal columns
- The anterior and middle columns fail in compression, and the posterior column fails in distraction
- Extend all the way through the spinal column: from posterior to anterior through the spinous process, pedicles, and vertebral body, respectively
- Unstable injuries and have a high association with intra-abdominal injuries.

What type of fracture is the following?

Flexion distraction injury
What type of fracture is the following?

Chance fracture
What are translational spinal fractures?
- All three columns have failed in shear
- Displacement in the transverse plane with alignment disruption of the spinal canal

What is the mechanism of injury of a chance fracture?
Flexion about an axis anterior to the anterior longitudinal ligament - e.g. seatbelt in a car crash
What type of fracture is the following?

Translational fracture
What types of thoracolumbar injuries fall under the category of tranlational fractures?
Rotational fracture-dislocations and pure dislocations
What criteria does a fracture have to meet to be classified as unstable?
Any one of:
- > 30o kyphosis
- > 50 % loss of vertebral height
- Both columns involved
- Pedicles splayed
What can cause spinal injury?
- Spinal fractures
- Motor vehicle accidents
- Falls from height
- Sports injuries
- Violence
- Penetrating injuries – gunshots, stabbings

