NWHSU Skel Rad 2: Written Midterm
Plain film tomography
-largely replaced by CT/MRI -two x-ray tubes travel around the patient -structures in axis of rotation are "in focus"
How do you draw and measure McGregor's line?
-line from the back of the hard palate to the base of the occiput -drop a line from the top of the dens to the 1st line -8mm is upper end
Radiographic findings of blocked vertebra
-small vertebral bodies -anterior concavity -hypoplastic intervertebral disc -involvement of posterior elements
Meyerding Grading scale Grade 1-5
1: up to 25% slip 2: 25-50% slip 3: 50-75% slip 4: 75-100% slip 5: vertebra fall's off = spondyloptosis can use "high" or low" for border cases
Typical views for imaging of spondylolisthesis of general lumbar region
AP Lateral lumbar (oblique for pars)
A sagittal cleft in a vertebral body (typically midline)
Butterfly vertebra -most common in thoracolumbar junction
Combination of spina bifida occulta of S1 and an elongated spinous process of L5
Clasp Knife syndrome -patient presents with "zingers" in low back during extension
Typically mistaken as fx or pathology, a horizontal channel created by vasculature
Hahn's (venous) clefts -created by the basilar vein
A sign commonly seen with grade 3 or 4 spondylolisthesis
Inverted Napoleon hat sign -seen on A-P lumbar view
Cervical blocks involving three or more vertebral bodies is called _____
Klippel-Feil syndrome
Webbed neck, low hairline, and reduced cervical range describe _____
Klippel-Feil syndrome
A spondylolisthesis is typed with this classification system (what is the cause?)
Newman/Wiltse
Can a DEXA Z-score be used to determine osteoporosis?
No. Having normal bone density for age does not mean the patient is not at risk for osteoporosis.
Non-union of the secondary growth center for the articular process, should be differentiated from acute fx
Oppenheimer's ossicle -most common: inferior articular processes L2, L3
This syndrome due to transitional L5 segment, an increased incidence of low back pain and intervertebral disc herniations at the level immediately superior
Bertolotti syndrome
In an MRI, bone displays as this color
Black
Rib process off the C7 transverse processes
cervical rib can be tiny or fully formed
Describe type 1 spondylolisthesis
congenital, dysplastic, hypoplasia of the arch agenesis of IAP/SAP, SBO can contribute to pars fx (type 2)
Failure of midline ossification of the neural arch. Gap is filled with fibrous tissue.
Posterior Spina Bifida Occulta of the atlas
Appears as one central calcification, may mimic a lung mass, supposedly more common in women
costochondral junction calcification "Wagging tongue" type
Appears as two parallel lines, may mimic a lung mass, supposedly more common in men
costochondral junction calcification "Railroad track" type
What type of scan will help determine if the fracture is "active" and able to heal
SPECT or MRI
-Multiple levels of Schmorl's node formation in mid-thoracic spine -anterior vertebral body wedging -increased thoracic kyphosis -associated back pain
Scheuermann's disease
Herniation of disc material into the vertebral body, most likely occurs during adolescence on immature endplates (thought to be weakened cartilaginous endplates and subchondral bone)
Schmorl's nodes
Describe type 3 spondylolisthesis
degenerative facet arthritis
Partial or complete fusion of the first and second ribs
Srb's anomaly (rib fusion = synostosis, typically unilateral)
DEXA T-scores: -what is a t-score? -what is normal? -ranges for osteopenia? -ranges for osteoporosis?
T-score: the amount of bone compared to a young adult, same gender, with peak bone mass normal: scores about -1 osteopenia: -1 to -2.5 osteoporosis: less than -2.5
T1 or T2 weighted image: The cerebrospinal fluid on the MRI is dark
T1 weighted
T1 or T2 weighted image: The cerebrospinal fluid on the MRI is bright
T2 weighted
Presents as two nerve roots exiting from one large foramen
absent pedicle
In the lumbar region, produced by failure of ossification of the neural arch
agenesis of a lumbar pedicle (may be hypoplastic)
If this is bilateral at L5, this predisposes the patient to a congenital spondylolisthesis
agenesis of the articular process -rare -most often involves L4 or L5
Asymmetrical facets in the lumbar region, typically due to poor remodel from coronal to sagittal orientation
facet tropism (best viewed on CT or MRI)
Symptoms of Arnold-Chiari malformation?
headaches neck pain
Barre-Lieou syndrome
headaches retro-orbital pain facial disturbance visual disturbance difficulty swallowing or talking
Failure of ossification of half of a vertebra
hemivertebra
During an MRI, a magnetic pulse (radiofrequency) is applied to flip the protons of the _________ and into the _______
horizontal plane transverse plan
Describe type 6 spondylolisthesis
iatrogenic: laminectomy intentional surgery
The endplates of the adjacent vertebra are altered to conform to the half of a vertebra
incarcerated hemivertebra
Three uncommon regions to find abnormal ribs
intrathoracic rib sacral rib pelvic rib -DDX: myositis ossificans =post-traumatic hemorrhagic bone formation
Describe type 2 spondylolisthesis
isthmic, lytic, fractures through the pars A: stress fx of pars (adolescence) **most common B: elongated pars (break, slip, heal) C: acute fx (very rare)
Multiple levels of schmorl's node formation in lumbar spine -looks like scheuermann's, but in lumbar
juvenile discogenic disease
Anterior unsegmented bars may produce marked ____
kyphotic deformity
Significant scoliosis may be caused by this type of half of a vertebra
lateral hemivertebra
Occur when the disc material herniates through the growth center of the ring apophysis, isolating the apophysis from the vertebral body
limbus bones -posterior limbus bones can result in compression of the spinal cord/nerve roots
An upper sacral segment with a separate posterior arch and lumbar transverse processes
lumbarization
Lowest lumbar or highest sacral segment demonstrates characteristics of both the lumbar spine and sacrum
lumbosacral transitional vertebra
Herniation of CSF filled sac
meningocele
Positron Emission Tomography (PET)
-patient injected with signal emitting *glucose* -glucose travels to metabolically active areas (cancer, metastasis) -signal detected by computer -> forms an image
How does technetium Tc 99m work?
-radioactive tracer -collects in areas of the body that are metabolically active via increased blood flow -gamma camera used to detect the "signal" emitted from the patient -"metabolic" or "physiologic" study -radiotracer shows areas of increased uptake = "hot spot"
Computed Axial Tomography: CAT or CT scan
-uses ionizing radiation to obtain cross sectional images of the body -patient in tube (gantry), x-ray tube travels around them -axial images created "like a really good x-ray"
When to use PET scans
-very sensitive for detecting cancer -useful for detecting coronary heart disease -useful for brain disorders: Parkinson's, Alzheimer's, seizure disorders -adds anatomical information to physiologic information
Agenesis of the posterior arch of the atlas
-a range of presentations -a cleft in posterior arch to unilateral agenesis to complete agenesis -dense connective tissue present at the site of bone agenesis -posterior arch should achieve union by age 6
Bone scintigraphy
-aka "bone scan" -complement to radiography -helpful for determining areas of metabolic activity in the body -VERY SENSITIVE, NOT SPECIFIC --cancer & stress fx look essentially the same (x-ray is "mediocre" sensitive)
Strengths of DEXA scan?
-more precisely documents small changes in bone mass -spine (Central DEXA) -extremities (peripheral DEXA)
Identify the 6 types of Spondylolisthesis:
1. congential 2. Pars fx 3. Degenerative facet arthritis 4. Fx anywhere but the pars 5. Pathology 6. Iatrogenic
What fraction represents the amount of Hydrogen in our bodies?
2/3
The occipital bone forms from how many somites?
4 or 5
A sac containing CSF and neural elements
myelomenigocele
Symptoms of occipitalization of the atlas?
neck pain begins about 30-40yrs early degenerative changes at C1/2, C2/3
The adjacent endplates are straight, more likely resulting in scoliotic deformity to the half of a vertebra
non-incarcerated hemivertebra
The hemivertebra is fused to an adjacent segment with no separating intervertebral disc
non-segmented hemivertebra
Absent pedicles are best seen on ______ views
oblique
Best x-ray for viewing pars
oblique (break in the neck of the "scotty dog")
A spondylolisthesis is detected with this line
offset of George's line (Ullmann's line may also be useful for subtle slips)
Identify the name of the occipital vertebrae that originates at the jugular process of the occiput and articulates with the TP of C1
paramastoid process
Describe type 5 spondylolisthesis
pathologic: any disease process that enlarges the vertebra or destroys the structures causing forward displacement paget's disease tuberculosis of bone
Anterior bowing of the sternum, seen in patients with Morquio's syndrome
pectus carinatum "pigeon breast deformity"
Anterior thoracic view shows vertical orientation of the anterior ribs as well as a left shift of the heart
pectus excavatum
Lateral thoracic view shows posterior displacement of the sternum
pectus excavatum -most common chest wall deformity (anterior concavity of the sternum)
May resemble a lytic (destructive) lesion of the rib
rib foramen (no clinical significance)
A lumbar segment that appears with large transverse processes
sacralization
How does a DEXA scan work?
scanner rapidly directs x-ray energy from two different sources towards the bone being examined and measures the amount of absorption
Failure of union between the two halves of the posterior arch, resulting in a midline cleft
spina bifida occulta -may cause pain with extension of the spine
Wide bony defect in the posterior arch, typically more than one segment, with protrusion of the spinal cord contents
spina bifida vera
Forward slip of a vertebral body, compared to the level below
spondylolisthesis
a break in the pars region
spondylolysis
degenerative disc disease including early osteophyte formation
spondylosis
Decreased AP dimension of the thorax, producing alteration of cardiac hemodynamics -pancake heart murmurs
straight back syndrome -ejection murmurs that decrease when the patient sits up or inspires -<12cm AP from anterior aspect of the T8 VB and posterior aspect of the sternum
To do a bone scan (bone scintigraphy), a patient must be injected with this radioactive tracer
technetium Tc 99m (half life = 6 hrs)
Best view to see pars of L5
tilt up view through the SI joint
Describe type 4 spondylolisthesis
traumatic fx of arch anywhere except the pars
On a CT scan, bone displays as this color
white
Occipitalization of the atlas is often associated with the following neurologic abnormalities:
Arnold-Chiari malformation syringomyelia hydrocephalus infarction (need MRI to view soft tissue anomalies)
Fusion of two or more verebrae from failure of somite segmentation in the 3rd through 8th week of development
Block vertebrae (non-segmentation)
Most common locations for block vertebrae
C2/3 C5/6 T12/L1 L4/5
Costal processes articulating with the transverse processes of C7
Cervical rib -may be fully formed or hypoplastic rib processes
In an MRI, the time between RF pulse and measurement of energy released is called ______
Echo time (when does the computer listen?) "TE" T1 weighted images = short (<20msec) T2 weighted images = long (>100msec)
This abnormality may alter biomechanics (focally), necessitate alteration of SMT, and is most commonly found at C5/6.
Elongated anterior tubercles with accessory joint
Basilar impression on lateral skull radiographs will present abnormal ______ and ______
McGregor's line Chamberlain's line
Failure of descent of the scapula during fetal development
Sprengel's deformity "pringles" - scapula too high, popped up (usually unilateral)
Associated anomalies of omovertebral bone:
Sprengel's deformity elevation of the scapula scoliosis hemivertebrae block vertebrae spina bifida occulta cervical ribs
This abnormality may be associated with dysphagia, feeling of fullness in the throat, or facial pain.
Stylohyoid ligament ossification
Hypoplastic/Agenetic odontoid process is associated with:
down syndrome occipitalization Klippel-Feil syndrome skeletal dysplasias atlanto-axial instability (& neurological symptoms)
How is Arnold-Chiari malformation treated?
enlargement of the posterior fossa
Identify the name of the of the occipital verebrae that originates from the TP of C1, projects superiorly, and articulates with the occiput
epitransverse "stalagmite" - from below reaching up lucency near occiput
How does an occipital or pro-atlas vertebrae form?
failure to unite of the most inferior somite
Hypoplastic ribs may have ____ extending from them which may produce compression fractures
fibrous bands
Hard to see, may see a vertical lucency superimposed over the odontoid on the APOM view. Lateral cervical view displays a bulbous/indistinct anterior tubercle.
anterior spina bifida occulta of the atlas
During an MRI, after the magnetic pulse (radiofrequency), protons relax __________
giving up their energy as RF signal
Superior position of the upper cervical vertebrae with relation to the skull is called
basilar impression
Associated anomalies of Platybasia
basilar invagination occipitalization block vertebrae Klippel-Feil syndrome
fusion of two or more vertebrae due to failure of segmentation of somites
block vertebra
The odontoid is considered _____ when it measures less than 12mm in height
hypoplastic
Which scan, other than MRI, will show associated conditions of Arnold-Chiari malformation (type I)?
X-rays -show occipitalization
Is occipitalization of the atlas a contraindication for adjustment?
Yes! rotation and extension moves may compromise the spinal cord and vertebral arteries
DEXA Z-score: -what is it?
Z-score: the amount of bone compared with other people in the same age group, size and gender
A short posterior arch may produce _____
central stenosis -closing off of space, not a lot of room for spinal cord
Occipitalization of the atlas is often associated with the following anomalies of the jaw/nose/ear and palate:
cervical ribs platybasia cervical block vertebrae odontoid anomalies Klippel-Feil syndrome laxity of the transverse ligament atlanto-axial instability
The following radiographic findings describe what anomaly? -defect in the posterior arch -spina bifida occulta of the involved segment -anterior displacement of the involved segment
cervical spondylolisthesis
The following typically results from a cleft in the posterior arch, most commonly at C6, but also seen at C2 and C4.
cervical spondylolisthesis
This radiographic finding is representative of which abnormality? -anterior concavity at the disc space
congenital block vertebrae
This radiographic finding is representative of which abnormality? -hypoplasia of the involved vertebral bodies in the A-P dimension?
congenital block vertebrae
This radiographic finding is representative of which abnormality? -thin intervertebral disc (w/ or w/o calcification)
congenital block vertebrae
This radiographic finding is representative of which abnormality? -variable fusion of the posterior elements
congenital block vertebrae
Complications of Platybasia
impingement of neural and vascular structures syringomyelia of the cord infarction of the brainstem or cerebellum Arnold-chiari malformation
Which views are appropriate to assess for os terminale/increased ADI?
lateral cervical flexion and extension
The reason an MRI works is because when placed in an external magnetic field, the protons will __________.
line up in the horizontal plane
Physical presentation of occipitalization of the Atlas
low hairline short neck restricted range of motion
What does a DEXA scan measure?
most widely used method to measure bone material density
Chronic upper cervical syndrome
neck pain occipital headaches vertigo
The following x-ray findings are indicative of what abnormality? -close approximation of C1 to the occiput -bony or fibrous fusion of C1 to the occiput -lateral cervical flexion/extension show lack of motion between C1/occiput
occipitalization of the atlas
Primary, or congenital, basilar impression is often associated with
occipitalization of the atlas spina bifida occulta of the atlas odontoid abnormalities cervical block vertebrae bone softening conditions (paget's, osteomalacia, RA, fibrous dysplasia)
Cartilaginous or fibrous band that runs from the C5/6 SP to the superior angle of the scapula
omovertebral bone -commonly associated with sprengel's deformity
Failure of the apical ossification center of the dens to unite to the body of the dens
os terminale (should unite by age 12-13) may produce atlanto-axial instability
Identify the name of the occipital vertebrae that originates slightly medial and anterior to the paramastoid process and articulates with the TP of C1
paracondylar process "stalactite" - from above going down lucency near edge of TP
Flattening of the skull base _______
platybasia
"Mega-spinous"
posterior arch of C1 joins the spinous of C2
Name for the ossification of the oblique portion of the atlanto-occipital membrane
posterior ponticle of the atlas
Radiographs show an absence of the spinolaminar junction line or the anterior tubercle of the atlas may appear sclerotic
posterior spina bifida occulta of the atlas
MRI uses what kind of waves?
radio waves
Condition known as Eagle's syndrome
stylohyoid ligament ossification
This abnormality may put pressure on the external carotid artery and surgical removal may be necessary
stylohyoid ligament ossification
Fusion of two or more vertebrae that demonstrate pertinent negatives implies _____
surgically blocked vertebrae
A midline bony projection bridging the anterior aspect of the foramen magnum with the apex of the odontoid process OR anterior arch of the atlas
third condyle
Occipital vertebrae may take the form of ____ (4)
third condyle paramastoid process epitransverse process occipital ossicle
Which ligament should you be concerned about if your patient has an os odontoideum abnormality?
transverse ligament
This term refers to less than 80% of the discovertebral junction fused between two levels
unsegmented bar
VBI
vertebral artery is firmly adherent to the ponticle -atlanto-axial movements may create traction on the artery, resulting in intimal tears
MRI detects which atom?
Hydrogen atoms
True or false: hydrogen is highly magnetic
True
A forked rib, may resemble a cavity in the lung
Luschka's bifurcated rib (most common rib anomaly, no clinical significance)
A spondylolisthesis is graded with this classification system (how severe is it?)
Meyerding
A common variation in the appearance of the vertebral body endplate, aka "cupid's bow"
Nuclear impression
Bone scans are useful for determining the presence/extent of:
Acute fx Stress fx Metastasis (exception: multiple myeloma) Infection Paget's disease Child abuse (physiologic activity & clinical picture)
CT scans excel at ______
Chest and Abdomen scans: -thorax -liver -urinary tract -GI tract -head trauma (acute brain bleeds: 0-3 days = CT, 4+ days = MRI)
What is a DEXA scan?
Dual Energy X-ray Absorptiometry
CT is useful for...
Imaging: -fine bony detail -cortical bone
If a patient presents with Platybasia, the best scan to evaluate neurologic structures is ________
MRI
If a patient presents with basilar impression, which scan technology should be used to asses their brainstem and cerebullum?
MRI
Which scan is best used to determine if your patient has an Arnold-Chiari malformation (type I)?
MRI or CT -low-lying cerebellar tonsils -triangular shaped cerebellar tonsils -"kinking" of the 4th ventricle
Non-union of the odontoid process with the body of C2.
Os odontoideum (should fuse by age 5-7)
In an MRI, the time between radiofrequency pulses is called ______
Repetition time "TR" -T1 weighted images = short (<1000 msec) -T2 weighted images = long (>1000 msec)
Basilar impression symptoms
occipital headaches visual disturbances dysphagia facial pain unsteady gait
Failure of separation of the most inferior occipital sclerotome results in
occipitalization of the atlas
