Week 5 Flashcards
What were canadian C-spine rules developed for?
Used to rule in the need for a radiograph following cervical spine trauma
What does it mean when a person is negative on the cervical spine rule?
It is almost certain that they do not have a c-spine fracture. (High sensitivity)
What does it mean when a person is negative on the cervical spine rule?
It does not necessarily mean that they have a fracture, but that a x-ray is needed to further rule out a possible C-spine fracture
What are the standard x-ray views for a cervical spine?
- Lateral view (standard)
- AP view (standard)
- Oblique view (special)
- Odontoid view (special)
- Swimmer’s view (special)
What are the characteristics of the lateral view that is used in a x-ray of the C-spine?
- Initial view
- Evaluate alignment, spacing, soft tissues & vertebrae\
- Stress View
- Standard cervical view
What is the AP view in a x-ray of the C-spine used to see?
Alignment, oblique fractures. This is a standard cervical view
What are the characteristics of the oblique view that is used in a x-ray of the C-spine?
Done only after fracture or dislocation are ruled out – neural foraminal narrowing and alignment of facet joints. This is a special cervical view to compare IV foramina
What is the odontoid view in a x-ray of the C-spine used to see?
C1-C2 relationship (mouth open). This is a special cervical view to assess atlas and axis
What is the swimmer’s view in a x-ray of the C-spine used to see?
View of C7–T1. This is a special cervical view used when
shoulder superimposition obscures C7 on a lateral view
What is the patient position during an AP view of the C-spine?
• Patient standing or supine
• Chin extended slightly
• Central ray centered on
C4, angled 15-20° cephalad (toward the head)
What part of the spine does the AP projection of the c-spine allow visualization of?
• Lower 5 cervical vertebral bodies • Upper 2-3 thoracic vertebral bodies • Interpediculate spaces • Intervertebral disc spaces • Superimposed transverse processes and articular pillars • Spinous processes
What types of conditions can be seen in an AP projection of the c-spine?
- Fractures: vertebral bodies C3-C7
- IVD space abnormalities
- Uncovertebral joint abnormalities
What is the patient position during a lateral view of the C-spine?
- Patient sitting or standing
- Shoulders depressed
- Chin elevated slightly
- Central ray centered on C4
What part of the spine does the lateral projection of the c-spine allow visualization of?
• Cervical vertebral bodies and interspaces • Articular pillars • Lower 5 facet joints • Spinous processes • C7-T2 may be visualized with enough shoulder depression, but usually starts to get radioopaque
What types of conditions can be seen in a lateral projection of the c-spine?
- Occipito-cervical dislocation, esp in stress views when the person is in 60degs or more of flexion
- Fractures
- Unilateral and bilateral locked facets
- IVD space and Atlanto-odontoid space abnormalities
What types of fractures can be seen in a lateral projection of the c-spine?
- Anterior and posterior arches of C1
- Odontoid process
- Vertebral bodies of C2-7
- Spinous processes
- Hangman’s fracture
- Burst fracture
- Teardrop fracture
- Clay-shoveler’s fracture
- Compression fracture
What are the characteristics of the performance of Hyperflexion or Hyperextension during a lateral c-spine x-ray?
- NOT attempted until fracture ruled out
- Performed to demonstrate normal movement (or lack of) due to trauma or disease
- Becomes less diagnostic if someone can’t get to 60 degs of flexion
What is the patient position during an oblique view of the C-spine?
• Patient upright or supine • Patient’s body and head adjusted to a 45° angle • Elevate chin slightly • Central ray centered on C4, angled 15-20° cephalad
What part of the spine does the oblique projection of the c-spine allow visualization of?
• Intervertebral foramina
and pedicles farthest from
film (closest to the central ray)
• Vertebral bodies
What types of conditions can be seen in an oblique projection of the c-spine?
- Intervertebral (neural) foramina abnormalities
* Apophysial joint abnormalities
What is the patient position during an odontoid/open mouth view of the C-spine?
• Patient supine • Patient opens mouth as wide as possible • Central ray centered on the midpoint of the open mouth
What part of the spine does the odontoid/open mouth projection of the c-spine allow visualization of?
- Atlas and axis through the open mouth
- C1-2 interspace
- Dens of C2 (primary target)
- Occipital base
- Occlusal surface of teeth
- Mandibular ramus
- Lateral mass of atlas
- Inferior articular process of atlas
- Spinous process
What types of conditions can be seen in an odontoid/open mouth projection of the c-spine?
• Fractures including: - Lateral masses of C1 - Odontoid process - Vertebral body of C2 - Jefferson fracture • Atlantoaxial joint abnormalities
What is the patient position during a swimmer’s view of the C-spine?
• Arm closest to film extended overhead
• Patient can rest head on arm in sidelying position
• Depress shoulder closest to central ray as much as possible
• Central ray centered on C7-T1
interspace
What part of the spine does the swimmer’s projection of the c-spine allow visualization of?
Lateral projection of the cervicothoracic vertebrae (C7-T2) between the shoulders
What types of conditions can be seen in a swimmer’s projection of the c-spine?
Fractures of C7, T1, and T2
What are the structures seen in the AP view of the c-spine?
- Uncus
- Spinous process
- Body
- Pedical
- Transverse process
- Superior articular process
- Inferior articular process
- Facet joint
- Transverse process T1
- 1st rib
What are the structures seen in the lateral view of the c-spine?
- Anterior arch C1
- Dens of C2
- Posterior arch C1
- Spinous process C2
- Vertebral body C3
- Intervertebral disc
space C3-4 - Lamina C5
- Articular pillar C6
What are the structures seen in the oblique view of the c-spine?
- Posterior arch C1
- Lamina C2
- Pedicle C4
- Intervertebral foramen C4-5
- Inferior articular process C5
- Vertebral body C6
- Superior articular process C7
What are the structures seen in the odontoid/open mouth view of the c-spine?
- Dens of C2
- Lateral mass C1
- Inferior articular facet C1
- Superior articular facet C2
- Lateral C1-C2 joint
- Spinous process C2
- Teeth
What are the structures seen in the swimmer’s view of the c-spine?
- Right humerus
- Right clavicle
- Left clavicle
- Left humerus
- Body C7
What are the things that should be seen/done on an x-ray in order to determine whether or not it is normal?
- Count the vertebrae
- Alignment of the ALL, PLL, posterior spinal canal and spinous processes on AP and lateral views
- All 7 vertebral bodies and C7-T1 joint space should be seen
What more than anything will key you into degenerative changes in the c-spine?
• Vertebral body irregularity looking at possible: - compression fracture - Schmoral nodes - osteoporosis - osteophytes • Disk space
What is the chamberlain line?
A line that we look at in terms of looking for alignment in the upper c-spine and is the line between the posterior margin
of the hard palate and the posterior aspect of the foramen
magnum.
True or False
The Odontoid process should not project above the chamberlain line for > 3mm
True, The Odontoid process should not project above the chamberlain line for > 3mm
What does it mean when the odontoid is >7 mm above the chamberlain line?
Indicative of cranial setting, which is often associated it neurologic issues
What are the common causes of the odontoid being >7 mm above the chamberlain line?
Bone softening diseases such as Paget’s, osteomalacia, and RA
What is McGregor’s Line?
A line associated with the upper c-spine and is drawn from the
posterosuperior margin of the hard palate to the most inferior surface of the occipital bone.
True or false
The Odontoid process should not project above the McGregor’s line for > 3mm
False, The Odontoid process should not project above the McGregor’s line for > 4.5mm
When does cranial setting exist when looking at the McGregor’s line?
Cranial setting exists if the apex of the dens is > 8mm above this line in males or >10mm in females
What is the Anterior Atlantodental Interval (AADI)?
On lateral views, measure the distance between the posterior margin of the anterior tubercle and the anterior surface of the dens.
What is indicative of instability when looking at the Anterior Atlantodental Interval (AADI)?
Distance >2.5mm difference is indicative of instability
Why are flexion and extension lateral views needed when visualizing the Anterior Atlantodental Interval (AADI)?
To see how dynamic the instability might be, because radiographs in neutral may miss 48% of cases of anterior atlantoaxial subluxation, and extension view may reduce
subluxation.
What is the most frequent cause of an increase in the Anterior Atlantodental Interval (AADI)?
Most frequent causes of increase AADI include trauma, Down syndrome, AS, RA,
psoriatic arthritis, and Reiter syndrome.
What are the factors for the elevated risk of instability?
• Trauma Patient with connective tissue disorders such as: • RA • Down’s Syndrome • Ankylosing Spondylitis • Os Odontoideum • Klippel-Feil Syndrome • Morquios Syndrome • Ehler-Danlos (Type 3) • Marfans Syndrome • Post-fusion
What are the clinical indicators of a cervical subluxation?
• Neck pain most common complaint • Feeling o head falling forward with flexion • Occipital headaches • Ear & facial pain • Weakness • Loss of endurance • Loss of dexterity • Parasthesias • Ataxia • Tinnitus/ringing of the ears • Vertigo • Visual disturbances • Dysphagia
What are the physical examination findings that are indicative of a cervical subluxation?
- Lhermitte’s sign
- Modified Sharp-Purser test
- Tone changes
- Gait disturbances
- UMN signs like hoffmans or babinski
What is a george line?
A smooth curve found on the lateral view, which connects the
posterior vertebral bodies
What are the characteristics of the george line?
• There should be a smooth curve. • Flexion & extension views my be useful for appreciating disruption. • Anterolisthesis(slipping forward of a vertebral body) or retrolisthesis (slipping backward of a vertebral body) may be evidence of instability due to fracture, dislocation, ligamentous laxity, or DJD
What is the cervical gravity line?
A vertical line drawn from
the apex of the dens, which should pass through the 7th cervical body.
What is the function of the cervical gravity line?
Allows gross assessment of where the gravitational stresses are acting at the cervicothoracic junction.
What is a prevertebral soft tissue?
A measure of the soft tissue in front of the vertebral bodies and behind the air shadow of the pharynx, larynx, and trachea
What is the measurement of the prevertebral soft tissue from C2-4?
Distance should not be >
7mm in the neutral position
What is the measurement of the prevertebral soft tissue from C5-7?
This distance should not be >
20mm.
What causes an increase in the prevertebral soft tissue?
Any soft tissue mass, post-traumatic hematoma, or neoplasm from adjacent structures will cause an increase.
What does a whiplash injury result in?
Results in sprain or intervertebral disc injury without fracture or dislocation
What is the typical radiographic appearance of a whiplash injury?
Straightening of the cervical spine due to severe muscle spasm, with the normal curvature reduced or reversed. Some anterolisthesis can be seen in the middle c-spine, but mostly shows the loss of lordosis
What are the most common sites of spinal fractures?
C1-C2, C5-C7 and T9-L2.
What is the cause of most spinal fractures?
Trauma due to:
• MVA – 50%
• Falls – 25%
• Sports injuries – 10%
What are the indications for imaging a spinal trauma?
Canadian C-spine rules.
If a head CT is indicated, when should it be performed?
C-spine CT also done at the
same time of an image.
What are the radiographic signs of instability?
• Displacement of vertebrae
• Widening of interspinous or interlaminar spaces
• Widening of facet joints
• Widening and elongation of the vertebral canal (seen
by a widening of interpedicular distances)
• Disruption of posterior vertebral line
What is a jefferson fx?
Burst fx of C1.
What is an Odontoid fx?
Fx of odontoid process of C2
What is a hangman’s fx?
Fx of posterior aspects of C2
What is a teardrop fx?
Avulsion of anterior vertebral
body with posterior subluxation
What is a clay-shoveler’s fx?
Fx of the spinous process
of either C6, C7, T1 or T2.
What is the usual MOI of a jefferson fx?
Blow to vertex of head
What happens in a jefferson fx?
Axial load transmitted through the cranium and occipital condyles into the atlas drives lateral masses of atlas outward
What does a jefferson fx result in?
Bilateral, symmetrical fractures of the anterior and posterior arches of C1 and disruption of
transverse ligaments
What is the MOI of an Odontoid Process Fracture?
Typically hyperflexion injuries or a congenital abnormality. Usually a high impact injury in younger people and is usually associated with low energy falls in adults
What is the usual direction of an Odontoid Process Fracture?
Odontoid process is usually displaced anteriorly, with associated forward subluxation of C1 or C2
What is an odontoid fracture classification based on?
Stability
What is a type 1 odontoid fracture classification?
A fx of upper part of
odontoid. It is a stable fx
What is a type 2 odontoid fracture classification?
A transverse fx through
the odontoid base, regardless of whether or not the tranverse ligament is intact. It is an unstable fx
What is a type 3 odontoid fracture classification?
A fx through the odontoid
base and extending into
body of axis. It is a stable fx
What is the MOI of a hangman’s fracture?
• Hanging described as a hyperextension and distraction
injury
• Hyperextension (face striking windshield during MVA) is
more common mechanism
What happens in a hangman’s fx?
Bilateral fractures through the pedicles of C2, with anterior dislocation / subluxation of the C2 body over C3. It is often with spinal cord compromise/tearing
What is a type 1 hangman’s fracture classification?
Fx through C2 pedicle,
extend between superior and inferior facets
What is a type 2 hangman’s fracture classification?
Type I fracture with concomitant disruption of C2-3 IVD
What is a type 3 hangman’s fracture classification?
Type II injury with C2-3 dislocation, usually in an anterior direction
___ is the most severe and most unstable cervical injury
A teardrop fx is the most severe and most unstable cervical injury
What causes odontoid process fxs?
Lower c-spine stiffness and osteoporotic changes in the upper c-spine, including missing trabeculae or thinning of the cortical bone
What is a teardrop fx?
A posterior displacement of the involved vertebra into the spinal canal, fracture of posterior elements, and disruption of soft tissues (ALL, PLL, ligamentum
flavum, etc.)
What happens in a teardrop fx?
As ALL tears, it avulses from the anterior vertebral body (leaves a small triangular “teardrop-shaped” fragment) and displaces anteriorly and inferiorly
What is the MOI of a Clay-Shoveler’s fx?
• Initially described as an acute powerful flexion injury, as
produced by shoveling in Australian clayminers
• Direct blow or indirect trauma from MVA may produce similar injury (hyperflexion)
What are the characteristics of a Clay-Shoveler’s fx?
- Fracture of posterior spinous process.
- Stable fx as posterior ligaments remain intact
- Occurs at C6, C7, T1 or T2.
What is the psychometrics of a CT of the c-spine?
Highly sensitive and fairly specific
___ may be indicated in instances where a fx is suspected, but is not seen on a x-ray
CT scan may be indicated in instances where a fx is suspected, but is not seen on a x-ray
___ are common areas in which degenerative changes occur – appear by age 30-40.
C4 – C7 are common areas in which degenerative changes occur – appear by age 30-40.
What are the signs of degenerative changes in the c-spine?
Decreased disk space, sclerosis and spurring of the
margins of the vertebral bodies
In patients with arm pain, an ___ plain film can often show narrowing of the foramina
In patients with arm pain, an oblique plain film can
often show narrowing of the foramina
A ___ is indicated for evaluation of a suspected herniated disk or neuological deficit.
A MRI is indicated for evaluation of a suspected herniated disk or neuological deficit.
How much bony destruction has to occur before metastatic lesions can be seen on a x-ray?
Upwards of 70-80%
True or False
Radiographs are highly specific, but not sensitive for metastatic lesions of the spine
True, Radiographs are highly specific, but not sensitive for metastatic lesions of the spine
What are the characteristics of metastatic lesions and radiographs?
- Low signal intensity relative to marrow signal.
- C3 lesion causing compression of the cord.
- Presented with rapidly worsening weakness of arms and legs.
What is normal on a T1 weighted MRI of the c-spine?
- High signal bodies
- Low signal cortical bone
- Intervertebral disks are well visualized
- Spinal cord with dark or low intensity
- CSF
What is normal on a T2 weighted MRI of the c-spine?
• Low signal bodies • Low signal cortical bone • Intervertebral disks appear with a lower signal • Spinal cord is a shade of grey • CSF is bright white
What does a decrease hydration & proteoglycan content, increased collagen & fibrosis appear like when looking at a MRI?
Decreased T2 signal and disk height.
What does annular tears appear like when looking at a MRI?
Focal increase T2 and diffuse disk bulge
What does a nuclear herniation thru annular tears appear like when looking at a MRI?
Focal disk contour abnormalities.
What does a nitrogen-filled nuclear clefts (vacuum disk) appear like when looking at a MRI?
Horizontal signal void T1 & T2. May fill with fluid (increase T2) when supine or flexed.
What does a calcified disk appear like when looking at a MRI?
Increase T1 when small amounts. Decrease T1 & T2 with more calcification.
What is a diffuse disc bulge?
When there is greater than a 50% increase in the circumference from normal
What is a broad based protusion of a disc?
When there is a 25-50% circumference increase
What is a focal protrusion of a disc?
A less than increase of 25% of the circumference
What is a disc extrusion?
The diameter of the actual projection is larger than its attachment point with the rest of the disc
What is a disc sequestration?
When a piece of the disc is no longer attached to the larger mass
What is a disc focal protrusion from the sagittal view?
The overall disc height is larger than the disc height of the projection
What is a disc extrusion from the sagittal view?
When the posterior aspect of herniation is larger than the normal disc height
What is a disc sequestration from the sagittal view?
When a piece of the disc is free floating and no longer attached to the disc itself
What is a cervical myelopathy?
When the actual changes of the disc essentially pinch the spinal cord, and is usually around when the spinal canal is less than 12-14mm or when the spinal cord is under 10mm
When is the spinal canal considered normal?
17-18mm across
What are the components of the cluster clinical findings in patients with a cervical myelopathy?
- Gait deviation
- Hoffman’s reflex
- Inverted supinator sign
- Babinski reflex/ up-going plantar response
- Age >45
What are the psychometrics of the clinical findings of cervical myelopathy?
1 out of 5 positive = 94% sensitive
3 out 5 positive: 99% specific
4 or 5 positive: Dx of cervical myelopathy
What are some other functional measures for cord compression?
- 6m walking time usual and max pace
- Shorter step length at usual and max pace
- Chair to stand time (5 reps)
- One leg standing time
- Step test
What is Myelomalacia?
An imaging finding that demonstrates cord damage. Easier to see on MRIs
What does it mean when you see small areas of high intensity, both in the sagittal and transverse view of the spine as seen in cases of Myelomalacia?
This shows cord bleeding and is highly indicative of poor recovery and doesn’t recover the same way
True or False
Fatty infiltrates that are seen in the multifidus on MRIs are reversible
True, Fatty infiltrates that are seen in the multifidus on MRIs are reversible
What are the views included in the typical plain film series of the thoracic spine?
AP and Lateral views
Why are the upper thoracic vertebrae are often difficult to
see on the lateral view?
Due to the shoulders.
What is the patient position for an AP view of the T-spine?
Patient supine or upright
• Hips and knees flexed in supine position to reduce
kyphosis
What are the structures seen in the AP view of the T-spine?
- Thoracic vertebral bodies
- Intervertebral disc spaces
- Transverse processes
- Costovertebral joints
What types of conditions can be seen in an AP projection of the T-spine?
• Fractures including: - Vertebral bodies - Vertebral end plates - Pedicles - Transverse processes • Fracture - dislocations • IVD space abnormalities
What is the patient position for a lateral view of the T-spine?
• Patient sidelying on affected side • Hips and knees slightly flexed (pad support to prevent lateral bending) • Pad support under lower thorax to keep spine horizontal • Central ray centered on T7
What are the structures seen in the lateral view of the T-spine?
• Thoracic vertebral bodies
and interspaces
• Intervertebral foramina
• Spinous processes
____ view may be needed to visualize the upper thoracic vertebrae
Swimmer’s view may be
needed to visualize the
upper thoracic vertebrae
What types of conditions can be seen in a lateral projection of the T-spine?
• Fractures including: - Vertebral bodies - Vertebral end plates - Pedicles - Spinous processes - Chance fractures • Fracture - dislocations • IVD space abnormalities • IV Foramina abnormalities • Schmorl nodes of the vertebral body
In a normal T-spine AP view, what are the structures that can be seen?
- Vertebral body
- Cardiac shadow
- Pedicle
- Spinous process
- Rib
- Intervertebral disc
- Costovertebral joint
- Transverse process
In a normal T-spine lateral view, what are the structures that can be seen?
- Vertebral body
- Intervertebral disc
- Pedicle
- Intervertebral foramen
- Rib
- Spinous process
- Inferior articular process
- Superior articular process
- Facet joint
____ gives good visibility to the entire health of a vertebral body
The pedicles gives good visibility to the entire health of a vertebral body
___ is highly specific finding for metastatic cancer in the thoracic vertebrae
A winking owl sign, where there is only one owl eye is highly specific finding for metastatic cancer in the thoracic vertebrae
When looking at a normal radiograph of the T-spine, we see something called the blockhead or the winking owl. What are the components of this?
- Head is body
- Eyes are pedicles
- Nose is spinous process
- Ears are trans process
What can be seen between the blockhead of a T-spine radiograph?
The disk space
What are the vertebral body irregularities that can be seen in a radiograph of the T-spine?
- Compression fracture: if the block is smushed or irregular
- Schmoral nodes: if there are defects in the IV endplate
- Osteoporosis: there will be changes in terms of the radiolucency and opaquity of a specific vertebral body
- Osteophytes formation along the IVD space, looking at zones of high intensity, where there has been bony growth
What are the characteristics of pedicle irregularity that we can see in a radiograph of the T-spine?
• Should be 2. If only 1 called the “winking owl sign”. • Metastatic disease selectively attacks pedicle and will cause anterior and posterior body fracture.
In order to determine what is normal, what are the key points to to when looking at a radiograph of the T-spine?
• Count the vertebrae
• Alignment on AP and
lateral views of the ALL, PLL, posterior spinal canal and spinous processes
What does a misalignment of the ALL and PLL indicate?
An anterolisthesis or retrolisthesis
What are the forms of vertebral body abnormalities that can be seen in a radiograph of the T-spine?
- Congenital changes in form of hemivertebras
- Fractures
- Scheuermann’s disease
What is the cause of scheuermann’s disease and what does it usually involve?
Can be caused from AVN or steroid use and involves both inferior and superior end plates that increase the thoracic kyphosis
How do we measure the thoracic kyphosis of the T-spine on a lateral radiograph view?
- On a lateral film draw a line parallel to the superior end plate of T1 and another line parallel to the inferior end plate of T12.
- Draw right angle to theses lines until they intersect.
True or False
The angle that indicates the measure of a thoracic kyphosis increases with age
True, The angle that indicates the measure of a thoracic kyphosis increases with age
What are the normal ranges for a person’s thoracic kyphosis?
- Young adult male 7-40°
- Older male 30-56°
- Young adult female 13-48°
- Older female 32-66°
What are the causes of some of the common abnormalities of the T-spine?
- Infection
- Metastasis
- Trauma
- Disk
- DJD
What is the usual cause of trauma in the T-spine?
Usually the result of an MVA or osteoporosis
In the case of a trauma, what should the AP and lateral view of the T-spine be evaluated for?
The AP view should be evaluated for alignment and
the lateral view evaluated for subluxation
In the T-spine, what can hyperflexion injuries result in?
Hyperflexion injuries can result in compression burst fractures with bony fragments projecting into the spinal canal.
Why are compression fractures of the middle and lower thoracic spine are common?
Due to osteoporosis.
What are the most common degenerative changes in the
thoracic spine?
• Spurs (hypertrophic osteophytes) – usually of no clinical significance
• Calcification of the anterior spinal ligament (diffuse idiopathic skeletal hyperostosis – DISH) – no clinical
significance
• Calcification of an intervertebral disk – usually seen in mid-thoracic region – a single disk is usually the result of trauma but multiple disk involvement may be due to
hypercalcemia or other causes.
Where is osteophyte formation (spurring) most common?
T10 and L1
What are the characteristics of osteophyte formation (spurring) in the spine?
- Common throughout the spine.
* Not usually clinically significant.
What is the cause of diffuse idiopathic skeletal hyperostosis
(DISH)?
Due to excessive bone formation at skeletal sites subject to normal or abnormal stresses, generally where tendons and ligaments attach to bone
Plain X-rays are not recommended for routine
evaluation of acute LBP within the first month of symptoms unless any which red flags are present?
- Recent significant trauma (any age)
- Recent mild trauma (age 50 or greater)
- Patient over 70
- History of prolonged steroid use or osteoporosis
___ conditions of the L-spine persisting beyond four to six weeks of conservative intervention can be diagnosed
with X-rays, bone scans, or laboratory findings
Chronic conditions of the L-spine persisting beyond four to six weeks of conservative intervention can be diagnosed
with X-rays, bone scans, or laboratory findings
What are the characteristics of the radiographs that should be ordered for the L- spine?
- AP and lateral plain X-ray views may be ordered.
- Routine use of oblique views is not recommended due to increased radiation exposure.
- Oblique views are warranted in cases where medical history, physical exam, or AP and lateral X-rays, suggest a spondylolisthesis or spondylolysis.
- Bone scan can detect physiologic reactions to suspected spinal tumor, infection, or occult fracture.
In the study on the cost effectiveness of L-spine radiography, what were the results of the study?
- No group difference in all health outcomes
- Higher patient satisfaction in x-ray group
- Higher direct costs in x-ray group
- Patient satisfaction can be increased using lumbar radiography but at an additional cost
What are the typical plain films in the L-spine?
- AP
- Lateral
- Oblique (special)
- L5-S1
What is the patient position for a AP view of the L-spine?
• Patient supine
• Knees flexed to reduce
lordosis and improve visualization of disc spaces
• The beam projects at the L3 level
In a normal L-spine AP view, what are the structures that can be seen?
- Lumbar vertebral bodies
- Intervertebral disc spaces
- Laminae
- Spinous processes
- Transverse processes
What types of conditions can be seen in an AP projection of the L-spine?
• Fractures including: - Vertebral bodies - Vertebral end plates - Pedicles - Transverse processes • Fracture - dislocations • IVD space abnormalities • Spondylolisthesis (inverted Napoleon’s Hat sign)
What is the patient position for a lateral view of the L-spine?
• Patient sidelying on affected side • Hips and knees slightly flexed (pad support) • Pad support under lower thorax to keep spine horizontal • Beam projection goes through the L3 space
In a normal L-spine lateral view, what are the structures that can be seen?
• Lumbar vertebral bodies and interspaces • Spinous processes • Pedicles • Lumbosacral junction • Profile of IV foramen (except L5-S1)
What types of conditions can be seen in a lateral projection of the L-spine?
• Fractures including: - Vertebral bodies - Vertebral end plates - Pedicles - Spinous processes - Chance fractures • Fracture - dislocations • IVD space abnormalities • IV Foramina abnormalities • Schmorl nodes • Spondylolisthesis (spinous process or step-off sign)
What is the patient position for a L5-S1 view of the L-spine?
• Patient sidelying on affected side • Hips and knees slightly flexed (pad support) • Pad support under lower thorax to keep spine horizontal • Beam projection goes through the L3 space
What part of the spine does the L5-S1 projection of the L-spine allow visualization of?
• Lumbosacral junction
• Lower one or two lumbar
vertebral bodies (Joints between L4-L5 and L5-S1)
• Upper sacrum
What is the patient position for an oblique view of the L-spine?
- Patient lying 45-60° oblique angle with affected side down
* Position places the zygopophysial joints on affected side into the plane of the central ray
What part of the spine does the oblique projection of the L-spine allow visualization of?
- Lumbar vertebral bodies and interspaces (neural foramen)
- Articular processes on side closest to table
- Zygapophysial joints on side closest to table
- The combination of all three structures make up the “Scottie Dog”
What types of conditions can be seen in an oblique projection of the L-spine?
- Articular process / facet abnormalities
- Pars interarticularis abnormalities
- Scottie Dog configuration
- Spondylolysis
In the scottie dog, what are somethings/lesions that will be of importance?
- Any cracks to the neck which is pars interarticularis
- Any posterior translation of the body and tail of the dog(which will be of the posterior aspects of the vertebra, specifically, the transverse of the spinous process.)
What system must we always be aware of when looking at radiographs?
Alignment: is there good frontal plane alignment
Bone
Cartilage
Soft tissue
The thoracolumbar spine is split into 3 columns, anterior, middle, and posterior. What is encased in the anterior column and what is its stability?
• Ant 2/3 vertebral bodies and
Ant. annulous fibrosis(AF), ALL
• Usually stable
The thoracolumbar spine is split into 3 columns, anterior, middle, and posterior. What is encased in the middle column and what is its stability?
• Post 1/3 vertebral bodies and
post. annulous fibrosis(AF), PLL
• Potentially unstable
The thoracolumbar spine is split into 3 columns, anterior, middle, and posterior. What is encased in the posterior column and what is its stability?
• Post arch, posterior facet joint and capsule, post ligament
complex, and Lig Flavum
• Unstable
What are the most common fractures of the lumbar spine?
• Wedge compression fractures affecting the anterior column
• Compression burst fractures with fragments that are retropulsed generally seen in the anterior and middle column
• Fracture of the pars interarticularis (spondylolysis) which if bilateral may cause a subluxation of the vertebral body
(spondylolisthesis). These occur in the posterior column
What spinal lumbar column is affected in a burst fracture?
The anterior and the middle columns will be compressed. The posteior column will either have none or there will be distraction
What spinal lumbar columns is affected by a seated belt (chance) fracture and what type of fracture would it be?
There will be none or compression at the anterior column, and the middle and posterior column will be distracted
What spinal lumbar columns is affected by a fracture-dislocation and what type of fracture would it be?
There will be either compression and/or rotation,
shear in the anterior column, or distraction and/or rotation, shear in the middle and posterior columns
What happens in a wedge compression fracture?
Failure of anterior column under compression forces (anterior or lateral flexion)
What do we see in an AP radiograph view of a wedge compression fracture?
- Buckling of lateral cortices
* Decreased anterior body height
What do we see in a lateral radiograph view of a wedge compression fracture?
- Decrease anterior body height
* Posterior body height maintained
What is a compression burst fracture?
Failure of anterior and middle
columns due to axial compression forces
What do we see in an AP radiograph view of a compression burst fracture?
- Vertical laminar fracture
- Increase distance between pedicles
- Splaying of posterior facet joints
What do we see in a lateral radiograph view of a compression burst fracture?
- Decreased anterior and posterior body height
- Comminution of vertebral body
- Fragments may be retropulsed into spinal canal
Why are CT scans and MRIs essential for visualizing a compression burst fx?
They give a much better view of how much osseous deformity there is
What causes a chance fx and where does it commonly occur?
Due to a flexion distraction injury, most commonly occurring at L1-L2
What is a chance fracture also known as and why is it known as that?
AKA Seat belt fracture
• Usually occur in rear seat passengers who only have lap belts, not shoulder belts
What is a chance fx?
Horizontal fracture with splitting of the spinous process, lamina, pedicles, and vertebral body
Up to 50% of patients that have chance fx’s are usually associated with what types of injuries?
Up to 50% have associated blunt trauma injuries (bowel, pancreas, kidney, liver )
For a chance fx, what form of imaging is more sensitive?
CT more sensitive than X-ray
A chance fx has 2 levels that is used to categorize it, one level and 2 level. What are the components of each level?
One level
- Chance fx: horizontal splitting of vertebra; no ligament disruption
- Rupture of ligaments and IVD
Two level
- Fracture of posterior column; rupture of ligaments and IVD
- Fracture of posterior and middle columns; rupture of ligaments and IVD
What is spondylolysis?
A fracture of the pars articularis without separation
What is spondylolisthesis?
A fracture of the pars articularis without separation, but it is less stable and there is translation or the columns anteriorly or posteriorly
When slipping/reduced stability of a spondylolysis fx, it becomes a spondylolisthesis, and is split into grades. How many percent slip/translation is there in grade 1?
If there is a 0-25% slip
When slipping/reduced stability of a spondylolysis fx, it becomes a spondylolisthesis, and is split into grades. How many percent slip/translation is there in grade 2?
26-50%
When slipping/reduced stability of a spondylolysis fx, it becomes a spondylolisthesis, and is split into grades. How many percent slip/translation is there in grade 3?
51-75%
When slipping/reduced stability of a spondylolysis fx, it becomes a spondylolisthesis, and is split into grades. How many percent slip/translation is there in grade 4?
76-100%
When slipping/reduced stability of a spondylolysis fx, it becomes a spondylolisthesis, and is split into grades. How many percent slip/translation is there in grade 5?
More than 100%, at which point it is spondyloptosis
What does the 2nd classification from wiltse-newman use to classify spondylolisthesis?
Etiology, such as:
- Dysplastic/congenital
- Ischemic
- Degenerative
What is the spinous process sign or step-off deformity?
There is loss of alignment of the posterior and anterior elements within the columns
What can an isthmic spondylolisthesis and a degenerative spondylolisthesis be caused from?
Either failures at the joint oe failures at the pars interarticularis
True or false
All spondylolisthesis in the spine come from a breakage of the pars interarticularis
False, All spondylolisthesis in the spine DO NOT come from a breakage of the pars interarticularis
In the frontal view of a x-ray with spondylolisthesis, wha do we see as the vertebral body slips forward?
The napoleon inverted hat sign
True or False
Lumbar spine degenerative changes are common
True, Lumbar spine degenerative changes are common. “wrinkles on the inside”
What do we generally see in the x-ray of a lumbar spine with degenerative changes?
- Disk space narrowing
- Osteophyte formation
- Stenosis of the neural foramina
- Facet narrowing
- Stenosis of the spinal canal
Another pathology that we look at when visualizing lumbar radiographs, is the presence of ankylosing spondylitis(AS) joint morphology. What is this disorder?
A rheumatic disorder associated with the presence of HLA-B27 biome markers.
What do we see in an ankylosing spondylitis(AS) joint morphology?
- A squaring of the vertebral bodies
- Thinning of the syndesmophytes sites
- Preservation of disc space
- Fusion of the hypophyseal joints
- Ossifications of the paravertebral ligaments
- “Bamboo” spine
What are the indications for someone with ankylosing spondylitis(AS) joint morphology?
- Morning stiffness of >30mins duration
- Improved with exercise and activity
- Not better with rest
- Waking because of LBP during 2nd half of the night
- Alternating buttock pain
- Pain duration >/= 3 months
When is there increased suspicion of a person that has ankylosing spondylitis(AS) joint morphology?
- Younger age (<45, usually between 25-32)
- Family history of ankylosing spondylitis
- History of psoriasis
- Uveitis: changes in kind of eye
- Dactylitis:
- Enthesitis(bony bilateral rheumatic complaints), esp heel pain
- Anterior chest wall pain, including decreased chest expansion
- Crohn’s dz/ulcerative colitis
- Good response to NSAIDS (76% in 48 hrs)
What is the physical presentation of a spine with ankylosing spondylitis(AS) joint morphology on a radiograph?
- ## Blocked formation of the vertebra, where you see the increased sclerosis at the articulating surface and the syndesmophytes changes anteriorly
What is spondylosis?
Essentially arthritis
____ is a fx that could be unilateral or undisplaced of the lamina, Spottie dog with a broken neck
Spondylolysis is a fx that could be unilateral or undisplaced of the lamina, Spottie dog with a broken neck
____ is a spottie dog with a head that has moved away
Spondylolisthesis is a spottie dog with a head that has moved away
What is primary osteoporosis?
Age related disorder in which
the density of bone mass is reduced leading to an increased risk of fractures. Caused by aging, changes in calcium and estrogen deficiency.
What is secondary osteoporosis?
A reduction in bone density resulting from other causes such as hyperparathyroidism, excess glucocorticoids (steroids),
malabsorption, multiple myeloma and others
When does a plain film show osteopenia(bone loss)?
Until bone loss is more than 30%. (not very sensitive)
What is the preferred method to measure bone density?
DEXA (dual energy x-ray absorptiometry)
How are results of the DEXA (dual energy x-ray absorptiometry) given?
Results are given as a deviation from the mean.
What is normal bone density according to the DEXA (dual energy x-ray absorptiometry)?
Normal bone density is within 1 standard deviation from the
young adult mean
According to the DEXA (dual energy x-ray absorptiometry), what is osteopenia?
1 – 2.5 SD below the mean
According to the DEXA (dual energy x-ray absorptiometry), what is osteoporosis?
> 2.5 SD below the mean
Osteoporosis occurs with longe term ___ use. What does it cause to the bones?
Osteoporosis occurs with longe term steroid use. There will be radiolucency of the vertebral body, as well as some sclerotic changes from increased strain
Sclerosis is classified based on curve angle, also known as the cobb angle. How is this angle calculated?
By looking at the upper margins of the vertebral body of the superior aspect of the curve and the lower aspect of the vertebral body on the lower aspect of the curve, with associated angle measured
True or False
Idiopathic scoliosis is very prevalent, and the vast majority of these presentation requires no treatment.
True, Idiopathic scoliosis is very prevalent, and the vast majority of these presentation requires no treatment.
True or False
The importance of prevalence studies in scoliosis is that
small degrees of scoliosis are common but larger curves occur much less frequently. Fewer than 10% of children with curves of 10 degrees or more require treatment.
True, The importance of prevalence studies in scoliosis is that small degrees of scoliosis are common but larger curves occur much less frequently. Fewer than 10% of children with curves of 10 degrees or more require treatment.
At what degree of scoliosis do we start to see cardiopulmonary impairments?
Around 30 degs
What are the congenital causes of scoliosis?
- The failure of the formation of an entire vertebra(hemivertebra)
- Failure of a formed segment
What are the indications for operative treatment of idiopathic scoliosis?
• Increasing curve in growing child • Severe deformity (>50 degrees) with asymmetry of trunk in adolescent • Pain uncontrolled by nonoperative treatment • Thoracic lordosis • Significant cosmetic deformity
For the diagnostic evaluation of LBP in patients with cancer, what advanced imaging modalities has a high sensitivity?
- MRI (0.83-0.93)
* Bone Scan (0.74-0.98)
For the diagnostic evaluation of LBP in patients with cancer, what advanced imaging modalities has a high specificity?
- MRI (0.90-0.97)
* Radiography (0.95-0.99)
For the diagnostic evaluation of LBP in patients with a herniated disc, what advanced imaging modalities has a high sensitivity?
- MRI (0.60-1.0)
* CT (0.62- 0.90)
For the diagnostic evaluation of LBP in patients with a herniated disc, what advanced imaging modalities has a high specificity?
- MRI (0.43-0.97)
* CT (0.70-0.87)
For the diagnostic evaluation of LBP in patients with an infection, what advanced imaging modalities has a high sensitivity?
• MRI (0.96)
For the diagnostic evaluation of LBP in patients with an infection, what advanced imaging modalities has a high specificity?
• MRI (0.92)
What are the parameters for a CT and MRI in a patient with LBP?
• Considered for sciatica or symptoms of spinal stenosis not
improved in 6 weeks
• Equally accurate for diagnosing herniated discs or spinal stenosis.
• Done immediately (with surgical evaluation) in patients
with symptoms of the cauda equina syndrome
For what condition is a MRI more sensitive and specific for compared to other imaging tests?
MRI is probably more sensitive and specific than other imaging tests for detecting infections or
malignancies causing back pain.
What were the results of a study that compared the use of a rapid MRI vs radiographs?
- Nearly identical outcomes (pain & disability)
- Patients and physicians preferred MRI over radiography
- Little or no additional benefit
- Increased costs ($2059 vs. $2380)
- More likely to have surgery with MRI group (4 vs.10)
What does a younger disc with less degeneration (Grade 1) look like on a MRI?
They have a high signal intensity in the nucleus pulposus, so there will be a stark contrast, between the darker annulus fibrosis and the high signal intensity nucleus pulposes. The white will be bright and homogenous
What does the 1st stage of degenerative joint changes (Grade 2) look like on a MRI?
Inhomogenous white with horizontal band
What does grade 3 degenerative joint changes (Grade 2) look like on a MRI?
Loss of clear distinction between the annulus fibrosis and the nucleus pulposes
What does grade 4 degenerative joint changes (Grade 2) look like on a MRI?
A collapsed disc space, where you lose the uniformity of the intervertebral endplate
What does grade 5 degenerative joint changes (Grade 2) look like on a MRI?
A full collapse of the IVD
What do areas of annular tearing look like on an MRI?
They are areas of higher intensity that demonstrate disruption and small elements of inflammation in the annulus fibrosis. These are a common finding
Why has the importance of an annular tear being increased?
They contribute to severity in back pain over a period of time
In what type of patient population does spinal infections occur?
Usually occur in diabetic or post-operative patients, and IV drug abusers
What does infections appear like?
Appears as a destructive process that involves or
crosses a disk space.
• As opposed to a tumor which does not involve the disk
space.
What type of imaging modality is preferred for the visualization of a spinal infection?
MRI preferred over a CT scan if possible
What are the indications for a MRI in cases of a suspected spinal infection?
- Localized pain
- Elevated ESR
- Fever
- Elevated WBC’s, or
- Blood culture.
What is the most common neoplasm in the spine?
Metastatic disease from cancer somewhere else in the body.
What are the primary cancers most likely to metastasize in the spine?
Lead kettle, prostate, kidney, thyroid, lung, and lymphoma
Spinal neoplasm lesions may be lytic or sclerotic. What do these mean?
A lytic lesion will cause radiolucency, while a sclerotic lesion may cause radio-opaquity
What are some examples of a lytic lesion?
Lung, kidney, breast, thyroid, colon cancer, or multiple
myeloma
What are some examples of a sclerotic lesion?
- Prostate CA (men)
* Breast, uterine, ovarian CA (women)
Since metastases arise in the red marrow, where do they most frequently occur?
They occur most frequently in the skull, ribs, spine, pelvis and
proximal humerus and femur
What is the best modality to loo for bone metastases?
A bone scan
What are the indications for a bone scan?
- Initial staging of lung, breast or prostate CA
- Bone pain
- Elevated alkaline phosphatate
- To evaluate the response to chemotherapy