Transcript Burst Fractures

A Class for Foreign MD Students
Spine Trauma
Dr. Yue Wang
王
跃
MD,
PhD
Department of Orthopedic Surgery
The First Affiliated Hospital, college of Medicine, ZheJiang University
浙江大学医学院附属第一医院骨科
Anatomy of the Spine

Cervical spine, C,

Thoracic Spine, T, 12

Lumbar Spine, L, 5

Sacrum, S, 5, fused

Coccyx, 3-4, fused
AP and Lateral View
Osteology: The Vertebra

The shape of the
vertebrae changes!
C
T
L
The Cervical vertebrae
atlas, C1
C3-7
axis, C2
The lumbar spine
The thoracic and lumbar vertebrae
Articular processes
Pars
Superior
Articular
Process
Pars
interarticularis
Zygapophyseal
Joint
(Facet Joint)
Inferior
Articular
Process
Arthrology

Intervertebral Discs

Fibrocartilaginous joint

Increase in size from C to L

Ratio remains the same

Make up 20-30% of length of column
The intervertebral disc
Two components: nucleus and anulus fibrosus
Major Ligaments of the Spine

Anterior Longitudinal Ligament - ALL

Dense band along anterior and lateral surface of the
vertebral bodies from C2 to sacrum

Posterior Longitudinal Ligament – PLL

Runs along posterior surface of vertebral bodies (anterior to
spinal canal)

Ligamentum flavum

Supraspinous lig. and interspinous lig.
Ligaments
Ligaments of the spine
Spinal Cord
Part of the CNS along with brain
 Contained within vertebral canal
 Extends from cranium to 1st-2nd lumbar
vertebrae
 Lumbar roots & sacral nerves for a
“horse-like tail” called cauda equina
 2 plexuses


Brachial, lumbosacral
Nerves
Each vertebrae has a nerve that exits
either below or above it
 31 pairs of spinal nerves

8 cervical nerves
 12 thoracic nerves
 5 lumbar
 5 sacral
 1 coccygeal

The thoracic spine
Spinal Injuries

Suspected spinal injuries
 High
speed crash: MVA
 Unconscious
 Multiple
injuries
 Neurologic
 Spinal
deficit
pain/tenderness
Spinal injury
• 5% worsen neurologically at hospital
• Protection is a priority
• Detection is a secondary priority
• Spinal evaluation complicated by multiple
traumae;
Mechanism of Injury
 Axial compression:
Compress/crush the C spine; tends to fracture the
vertebra into pieces
 Distraction
 Pull apart the spinal elements
 Usually associated with flexion or extension forces
Mechanism of Injury
Mechanism of Injury
 Flexion:
 Severe forward bending
 In cervical spine, often leads to neurological
damage
 Extension:
 Severe backward bending
 Not always associated with neurological trauma
Mechanism of Injury
Mechanism of
Injury
 Shear:
Mechanism of
Injury
 Rotational
Rescue
 Save
the life: ABC;
 Evaluate/identify
a patient with spinal
injury;
 Using
a spinal board;
 Determine
appropriate disposition;
Classification of Neurologic
Injury
Frankel Score

A: Complete loss of motor and sensory function

B: Only sensory function remains

C: Motor function is present but of no practical use
(i.e., can move legs but not walk)

D: Motor function impaired (i.e.can walk but not
with normal gait)

E: No neuro impairment noted
Diagnosis
Spinal injury
• Physical examinations;
• X-ray;
• CT;
• MRI;
• Electromyogram (EMG);
C Spine Injury

The C spine is involved in more than half of
all the patients with traumatic spine injuries

Stability is a crucial key point to determine the
choice of management, and it is determined by
the integrity of the anatomical structures
constituting the cervical spine

Lesions with spinal cord involvement are unstable
One of the most common pitfalls in
patients with cervical spine injury is
missed or delayed diagnosis!

Reasons:
1) inadequate radiographs (44%) ;
2) misinterpretation of adequate
radiographs (47%)
Goals of Management

Decompression

Alignment

Stabilization

Reconstruction, if necessary
Adequate management
starts from

A proper classification of the injury type

Assessment of stability of the affected segment
Instability : “the loss of the ability of the spine
under physiological loads to maintain
relationships between vertebrae in such a way that
the spinal cord or nerve roots are not damaged or
irritated and deformity or pain does not develop.
Stable or unstable





Lesions with spinal cord involvement are severe and unstable
and require surgical management.
On the other hand, lesions without spinal cord involvement
can evolve toward a stable or unstable lesion
Lesions that mainly involve bone structures may determine
temporary instability.
Successful fracture healing (with bony callus formation) and
subsequent stabilization of these lesions may be obtained
with reduction and immobilization.
On the other hand, ligamentous or osteo-ligamentous lesions
may cause irreversible instability with secondary dislocation.
Imaging Evaluation

Alignment/Bones /Soft Tissue

Look for
 Normal atlanto-occipital alignment
 Predental space 3 mm or less
 Prevertebral soft tissue space less than 5 mm
anterior to C3
 Spinal canal plain film AP diameter 13 mm or
greater
 Any horizontal translation of one vertebra on
the next
 Fanning of the space between spinous
processes
 Fracture of any bone
Upper C spine trauma
 Jefferson’s fracture
 Burst fracture of rings of C1
 Sometimes without neurological
deficit
 Hangman’s fracture
 Involves C2
 Sudden hyperextension of head and
neck forces vertebrae against spinal
cord
 Complete neurological loss
Radiograph
Odontoid fractures
 Type 1 fractures at tip
 Type 2 fractures at waist
 Type 3 fractures at base
MRI
Lower C Spine Fractures
n
Facet joint dislocation
 May occur without fracture
 Possible spinal canal compromise
Thoraco-lumbar fractures
 axial


may result in anterior discoligamentous disruption and
posterior compression fractures of facets, laminae, or spinous
processes
rotation


the posterior ligamentous and osseous elements fail in tension
hyperextension


Axial load may result in a burst fracture
flexion/distraction


compression
Combine compressive forces and flexion/distraction
mechanisms and are highly unstable
shear

Shear forces produce severe ligamentous disruption and are
often associated with spinal cord injury
Classifications
 White
and Panjabi defined clinical instability of
the spine :
Loss of the ability of the spine under
physiologic loads to maintain relationships
between vertebrae in such a way that there is
neither damage nor subsequent irritation to
the spinal cord or nerve root and, in addition,
there is no development of incapacitating
deformity or pain from structural changes.
Denis’ 3 columns theory &
Classifications

minor and major injuries:

minor injuries

included fractures of the
articular, transverse, and
spinous processes as
well as the pars
interarticularis.

Major injuries

were divided into
compression fractures,
burst fractures, flexiondistraction (seat-belt)
injuries, and fracture
dislocations
Wedge/compression fractures
These injuries may involve both endplates(A),
the superior endplate only(B),
the inferior endplate only (C), or
a buckling of the anterior cortex with both endplates
intact (D)
Burst fractures





Five subgroups:
type A fracture is characterized
by #’s of both the superior and
inferior end plates, usually as a
result of an axial load.
The types B and C burst
fractures involve the superior
and inferior end plates,
respectively. result from an axial
load coupled with a flexion load.
An axial and a rotational load
give rise to a type D burst
fracture.
The type E fracture is
characterized by widened
pedicles with a burst and lateral
flexion injury.
Flexion-Distraction fractures
(Seat-belt/Chance Fractures)
Fracture dislocations
General guidance
Treatment based on Denis
classification
 Wedge
 most
Fractures
treated with external orthosis
 surgical
indications:
 failure
of brace  progressive deformity
 >50%
height loss
 >30°
kyphosis
 Burst
 canal
Fractures
compromise & neuro deficit should be treated
with surgical decompression
 Consider non-operative if:
 neuro intact
 kyphosis <20-30°
 residual spinal canal > 50%
 anterior body height > 50% of posterior height
 posterior column intact
 purely boney injury
 show stability in supine/upright x-rays in brace

Seat-belt/Chance Fractures




usually unstable
if purely osseous injury  consider trial of bracing and close
serial xray f/u
if ligamentous injury  healing less predictable, probably best to
do posterior fusion
Fracture-Dislocation




generally all unstable and require surgery
associated with >75% neuro injury (1/2 of which are complete),
dural tears, exposed/avulsed roots
usually posterior fusion (early anterior fusion dangerous since
associated visceral injury is common)
staged anterior decompression if necessary
Case 1
Post-operative surgery
Case 2
Post-operative
Thanks!
The Rock Mountain, 2012