Midterm Flashcards
What is the relationship between occipitalization and basilar invagination?
Occipitalization (non-segmentation of the occiput from C1) can coexist with basilar invagination (odontoid encroachment into foramen magnum, potentially causing narrowing of the foramen magnum)
Where is the posterior ponticle?
Common variant found on the oblique portion of C1 d/t ossification of posterior atlanto-occipital ligament
Contains the vertebral artery and 1st cervical nerve
During neck manipulations, this variant leads to compression and traction of the vertebral artery
What is the significance of George’s line?
Helps to evaluate vertical body displacement (anterolisthesis or retrolisthesis)
It is an imaginary, curved line that can be drawn at each of the three levels of vertebrae which touches the posterior aspects of the vertebral bodies in that section.
Why is an os odontoideum clinically significant?
An os odontoideum (separation of the dens from C2) is clinically significant because cervical adjustments are particularly dangerous in those with this condition.
What are the radiographic differences between an anomalous block vertebra and an acquired fusion of the spine?
block vertebra - “wasp waist” appearance (anteroposterior diameter at level of joint space smaller than diameter at superior and inferior limits of involved vertebrae) - leads to DJD
acquired fusion - hardware may be visible, disc removed
What is the significance of the spinolaminar junction and spina bifida occulta in the lateral view?
In spina bifida occulta, there is a lack of a spinolaminar junction in the lateral view
On AP view, this appears as a cleft spinous process
Why is it common to see disc space narrowing adjacent to a limbus vertebra and/or Schmorl’s node?
Both anomalies are due to a herniation of the nucleus pulposus through the vertebral endplate, reducing the disc space
How can you tell whether a rib at the cervicothoracic junction is a cervical rib or first rib?
Cervical rib is an extra rib arising from C7
Orientation of the TVP (T1 point up, C7 points down)
Cervical ribs only b/l 2/3rds of the time
Cervical ribs usually isolated to C7
Cervical ribs may lead to TOS
What is a transitional lumbosacral vertebra?
It can be either a sacralized L5 or a lumbarized S1.
They are undifferentiated and may be partially fused.
Hypoplastic disc, degeneration may be present
TP is spatulated (extended) further than it normally would be
Associated with Bertolotti’s syndrome
Name a dysplasia that may be present with tall stature and hyperbole joints?
Marfan’s syndrome (disease of CT w/ abnormal collagen formation)
What complications may be caused by Marfan’s syndrome?
CV (aortic aneurysm / dissection, valve malformations)
Eye (lens dislocation, retinal problems, early-onset glaucoma / cataracts, myopia)
Skeletal (scoliosis, pes excavatum, hip dislocations, gen recurvatum - knees bend backwards, patellar dislocations, pes planus - flat feet)
What is the most common cause of dwarfism?
Achondroplasia (bone growth d/o)
What neurologic condition may those with dwarfism have that affects the legs?
Infant - small foramen magnum, hydrocephalus leading to cord compression
Adult - spinal stenosis leading to paraplegia
Fragile osteopenia bones are associated with which dysplasia?
Osteogenesis imperfecta (brittle bone dz, blue sclera)
What are the radiographic findings of new vs. old fractures?
Hemorrhage, hematoma, step defect, and zone of impaction/condensation all indicate a fracture less than 2 months old
Old fractures show contiguous disc degeneration, osteophytes
