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188 Cards in this Set
- Front
- Back
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5 basic densities, in order of blackest to whitest |
air, fat, soft tissue/fluid, calcium, metal
(CT scan expands the gray scale) |
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requisition or x-ray order must include:
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Hx, PE findings, relevant lab findings, clinical diagnosis |
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radiologist report must include:
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demographics, clinical info, descriptive info, diagnostic conclusion
(can give prelim. direct report in emergencies) |
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Yearly background radiation exposure in the US is about...
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6.2 mSv (more at higher elevations) |
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How much radiation exposure assoc. w/ smoking, per year?
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about 2.8 mSv |
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How much radiation exposure assoc w...- PA chest x-ray- head CT- abdominal CT |
PA chest x-ray = 0.02 mSv head CT = 2 mSv abdominal CT = 8 mSv |
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How much radiation exposure to change blood chemistry? To cause nausea?
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blood chemistry = 5-10 rem nausea = 50 rem
(1 rem = 10 mSv) |
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How many bones in the skull?
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22 (8 cranial, 14 facial) |
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vascular indentation vs. fracture line?
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vascular indentations branch & taper; fracture lines do not |
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linear skull fracture
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most common type of skull fracture; usually temporal or parietal (w/ parietal, middle meningeal artery!)
little importance other than looking for other injuries, e.g. epidural hematoma |
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depressed skull fracture
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more likely assoc. w/ brain injury; high-energy blow to small area; often frontoparietal & comminuted;
surgical elevation if fragment is deeper than inner table
may see white lines of overlapping bone |
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basilar skull fracture
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most serious type of skull fx; is linear fx at base of skull
assoc. w/ tears in dura mater w/ CSF leak (rhinorrhea, otorrhea) |
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When should we suspect a basilar skull fracture?
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air in the brain (pneumocephalus), fluid in mastoid air cells, air-fluid level in sphenoid sinus
can't always see basilar fx on x-ray |
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infraorbital canal
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part of orbit floor; carries maxillary branch of trigeminal nerve which can be injured in fx |
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upper McGrigor-Campbell line
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passes though zygomatic-frontal sutures & across upper edge of orbits |
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middle McGrigor-Campbell line
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follows zygomatic arch, zygomatic bone, inf. orbital margins |
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lower McGrigor-Campbell line
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passes through condyle & coronoid process of mandible, & through lat. & med. walls of maxillary antra |
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isolated zygomatic arch fracture
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disruption of middle McGrigor line; typically med. & inf. displacement of fragments |
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tripod fracture
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fx all 3 limbs of the zygomatic bone (orbital process, arch, maxillary process)
seen in OM & OM30 w/ soft tissue swelling & opacification or air-fluid level in maxillary sinus
disrupts all 3 McGrigor lines |
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orbital blowout fracture
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trauma to orbit -> increased IOP -> fx of bone that forms orbit floor
maxillary antrum fat/muscle may herniate downward, forming soft tissue teardrop in roof of maxillary sinus |
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orbital emphysema
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tripod or blowout fx may cause leak of air from maxillary antrum into orbit;
"black eyebrow sign" |
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all LeFort fractures transect... |
the pterygoid process of the sphenoid bone |
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LeFort I |
transverse fx through inf. maxillary antra; separates from alveolar process of maxilla
OM view: fxs seen thru med./lat. walls of maxillary antra & nasal septum
produces a floating palate |
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LeFort II
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pyramidal fx; separates from central face
OM: fxs thru nasal bone/septum, med. orbital walls, infraorbital rim, lat. walls of maxillary antra
produces a floating maxilla (zygomatic arches not included in this fx) |
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LeFort III
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floating face post. aspect of fx extends down post. maxillary sinus walls
OM: fx from med. orbits & nasoethmoid region across the ethmoids posteriorly
Orbits elongated w/ wide zygomatico-frontal sutures (fx of orbital process of zygoma) |
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nasal fracture
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linear & transverse, due to direct frontal impact; usually lower 1/3 of nasal bone;
most are depressed or displaced can cause step-off of nasal bone on lat. view
OM: mediolateral displacement of fx fragments |
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mandible fracture
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considered a "ring" of bone; if one break, look for a 2nd or a TMJ disloc.
has inner & outer cortex; lines may be on both but is only one fx
most common fx: body, angle, condyle, symphysis menti |
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views of the mandible?
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Orthopantomogram (Panorex) PA Mandible & Lateral Obliques
(both needed; fx often only seen in one) |
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Panorex
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shows mandibular fxs, including coronoid & condylar processes; but may miss symphysis menti fx
air in pharynx may overlie condyle & ramus; can be mistaken for a fx follow cortical edge & check TMJ |
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PA mandible view
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supplements panorex;
shows displacement, body, symphysis menti; tangential view of rami/necks of condyles; angulation of condyle |
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cervical vs. thoracic & lumbar vertebrae
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cervical are the smallest & have foramen transversarium in each transverse process (transmits vertebral artery) |
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odontoid (dens)
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part of C2; articulates w/ anterior arch of C1; held in position by transverse ligament |
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NEXUS criteria(Who needs cervical x-rays?)
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post. midline tenderness on palp. intoxication altered mental status neurological signs distracting injury |
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If ant. height of a vertebral body is >= 3 mm less than the post. height...
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suspect a wedge compression fracture
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On a lateral c-spine view, where is the spinal cord?
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between the post. & spinolaminar lines; is not visible |
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soft tissue swelling from fxon lateral c-spine x-ray
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due to hematoma; not always present;
Normal: C1-C4 = 4-7 mm C5-C7 = 16-20 mm (equal to vert. body width)
Above C4 =<1/3 vert. body width Below C4 =<100% vert. body width |
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Harris' ring
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lateral masses of C2 viewed side-on; fx might be seen as disruption of ring outline |
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Distance between post. aspect of C1 arch & anterior aspect of odontoid should be...
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no more than 3 mm in adults |
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AP vs. lateral view of c-spine
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AP is less informative; only shows lat. aspects of vertebral bodies |
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On AP view of c-spine, if distance between spinous processes is 50% wider than one immediately above or below it, suspect..
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an anterior cervical dislocation |
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In order for odontoid (Open Mouth) view to be adequate, it must...
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show alignment of the lateral processes of C1 & C2
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swimmer's view
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oblique image w/ humeral heads projected away from the C-spine;
raise one arm over head while lowering the other |
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flexion injury to c-spine
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up to 80% of all c-spine injuries; max force on bodies of C4-C7 |
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flexion injury to c-spine
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may tear at intervertebral space or margin of vertebral body;
avulsion fx of ant. sup or inf margin of body; post. elements also compressed |
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axial compression injury to c-spine |
initial trauma to vertebral endplates; disc explodes into vertebral body, causing comminuted fx |
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distraction injury to c-spine
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movement of head = tensile forces on c-spine;
if in combo w/ flexion or extension, lessens compression but may injure interspinous ligaments |
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rotation injury to c-spine
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can injure spinal ligaments (which are usually unaffected in compression/distraction); can lead to fx of post. elements |
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anterior column of the spine
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ant. 2/3 of vertebral body/intervertebral disc, & the ant. longitudinal ligament
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middle column of the spine
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post. aspect of vertebral body/intervertebral disc, & the post. longitudinal ligament |
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post. column of the spine
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post. elements (lamina, fect joints, spinous processes, assoc. ligaments) |
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atlanto-occipital dissocation
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caused by hyper-flexion or -extension; malaposition of occipital condyles relative to sup. facets of atlas;
is unstable
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Burst (Jefferson) fracture |
C1 (atlas) fx; from axial compression
misalignment of lat. masses w/ occipital bone (above) & C2 (below); widened space btwn dens & C1 lat. masses
can be stable or unstable |
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When is a Jefferson fx considered stable? |
stable: overhang of C1 on C2 <7mm
unstable: overhand >7mm; indicates transverse ligament distruption |
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odontoid fx
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most common C2 fx; from flexion or extension, usually w/ ligamentous instability
lateral view usually best; look for disrupted Harris' ring, ant. tilt of odontoid;
only sign may be swelling |
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Hangman's fracture |
high force hyperextension injury; (e.g. hitting a dashboard)
fx of C2 pedicles, ant. displacement of body & dens (from disruption of ant. long. ligament) |
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extension teardrop fracture
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hyperextension -> avulsion of ant. inferior corner of vert. body, most commonly C2
ant. long. ligament remains attached to fragment, which is now separate from body |
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flexion teardrop fracture |
any level between C3-C7; from hyperflexion & compression (e.g. dive into shallow water);
post. lig. disruption & ant. compression fx of vertebral body (is unstable) |
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Flexion teardrop fx is best seen on what view? |
lateral view;
prevertebral swelling (ant. long. lig. tear), teardrop fragment from avulsion fx, post. vert. body subluxation, spinal cord compression, fx of spinous process |
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anterior wedge compression fx |
from hyperflexion; height of vert. body decreased anteriorly; post. elements remain intact;
stable injury |
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burst fracture |
from axial compression; disc driven into vert. body -> body bursts;
unstable injury (freq. causes spinal cord inj.)
check post. vertebral cortex for disruption |
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spinous process fracture |
aka clay shoveler's fx; repeated forced flexion assoc. w/ shoveling; avulsion of spinous process (usually C6, C7; caused by supraspinatous ligament);
usually nondisplaced, so only seen on lat. view |
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whiplash |
flexion & extension of c-spine; sprain or disc injury w/o fx or dislocation
straightening (reverse curvature) of c-spine from muscle spasm |
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c-spine dislocation injury |
can be transient w/ spontaneous reduction, or locking of facet joints - prevents reduction;
bilateral or unilateral; prevertebral soft tissue swelling; high risk of cord damage
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MOI: bilateral locked facet |
hyperflexion w/o axial compression; complete ant. dislocation of vertebral body
high risk of cord damage, unstable injury |
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bilateral locked facet on x-ray |
best view: lateral
ant. dislocation of vert. body by half or more of the vert. body AP diameter; disrupted post. lig. & ant. long. lig.;
"bow tie"/"batwing" = overriding locked facets |
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MOI: unilateral locked facet |
from simultaneous flexion & rotation causing facet joint dislocation/ligament rupture |
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unilateral locked facet on x-ray |
best view: lateral & oblique
ant. dislocation of vert. body by less than half of vert. body AP diameter;
discordant rotation above/below level; facet w/i intervertebral foramen on oblique; widened disc space
"bow tie"/"batwing" = overriding locked facets
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spondylosis |
osteoarthritis of the spine; disc space narrowing & osteophytes; may impinge nerve root foramina
fall onto forehead in elderly w/ spondylosis = fx |
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swelling of prevertebral soft tissue w/o history of trauma... |
may have retropharyngeal abscess
(also look for reversal of normal c-lordosis, air-fluid level, gas) |
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epiglottitis |
+ thumbprint sign; loss of valecular airspace, distended hypopharynx, straightening of c-spine |
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Causes of false prevertebral swelling? |
oblique lateral view, neck flexion, crying |
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croup on x-ray |
AP view: subglottic narrowing - steeple sign
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S/Sx of foreign body is esophagus/trachea |
visualization, widened pre-vertebral shadow, loss of lordosis
esophagus = coronal plane trachea = sagittal plane (best on lateral) |
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retrosternal space on lateral CXR |
radiolucent behind sternum, anterior to ascending aorta
anterior mediastinal mass may fill it in |
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major & minor lung fissures |
Major: T5 to diaphragmatic surface behind sternum; not seen well on PA b/c oblique
Minor: divides RML from RUL; horizontal line on right at level of 4th anterior rib
If fluid in fissure, may see density at the lower lateral margin |
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right vs. left hemidiaphragm |
right: entire length visible, slightly higher than left side
left: silhouetted by heart anteriorly, stomach air or splenic flexure below |
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costophrenic angles |
sulcus = lowest point when upright; may be blunted if effusion
post. costophrenic angle = best on lat. CXR; lateral sulcus = best on PA |
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How much pleural effusion is needed for it to be detectable? |
lateral view = 75 cc
frontal view = 250-300 cc |
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spine sign |
spine looks whiter just above the diaphragm; seen on lateral view (e.g. pneumonia) |
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using lateral decubitus to evaluate air trapping? |
dependent lung should increase in density due to atelectasis from wt of mediastinum putting pressure on it;
failure to increase in density = air trapping |
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inspiratory/expiratory views |
x-rays normally shot during inspiration;
expiratory view may better reveal pneumothorax |
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technically adequate penetration on CXR |
spine appears darker as you move caudally; sternum is seen edge on; posteriorly, see 2 sets of ribs |
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technically adequate inspiration on CXR |
want full inspiration; diaphragm at 8-10th post. rib
poor inspiration compresses lung markings -> misdiagnosed lower lobe pneumonia |
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technically adequate rotation on CXR |
assess distance between clavicle heads & spinous process
equidistant = no rotation |
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technically adequate magnification on CXR; PA vs. AP |
PA: x-ray tube 6ft away
AP: x-ray tube 40 inches away (pulm. vasculature looks diff b/c pt is supine) |
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why order a CXR? |
cough, fever, chest pain, SOB, trauma |
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May need CT to better define the location of a chest mass. It can be either.. |
intraparenchymal, pleural, extrapleural |
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SVC on frontal x-ray |
straight soft density within RUL, extending from clavicle to RA
mass or adenopathy may displace it |
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right heart border on frontal x-ray |
disease on RML may obscure right heart border;
in RA enlargement, interface more prominent |
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aortic arch on frontal x-ray |
aortic arch interfaces w/ ULL, forms distinct knob
if aorta is injured/has anerysm, interface will be distorted |
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left heart border could be obscured by... |
a lingular infiltrate |
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widened mediastinum w/ trauma could be... |
an injured aorta; normal contours are obscured, may see air - pneumomediastinum |
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hilum |
junction of lung w/ the mediastinum; L hilum usually projects higher than R
unilateral enlargement = malignancy, TB, pulm. artery enlargment
bilateral enlargement = lymph node or pulm. artery enlargement |
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identifying a pneumothorax |
pleural line parallel to chest wall; lung markings not seen at periphery
expiratory view allows easier identification |
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normal cardiothoracic ratio |
0.5 or less;
only measured accurately on PA view |
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RA & LA enlargement |
RA enlrg. on PA = >5.5 cm from midline
LA enlrg. = displaces esophagus to R & ascending aorta to the L |
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pericardial effusion |
global & globular enlargement of heart |
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causes of air bronchograms |
lung consolidation, pulmonary edema, severe interstitial disease, neoplasm, normal expiration |
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signs that a pulmonary nodule is benign |
unchanged for 2 years, completely calcified or stippled calcium
(irregular calcification or those that are off center = suspicious; need w/u) |
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atelectasis in general |
loss of volume in lung -> increased density; lung becomes whiter
one of most common findings on CXR |
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subsegmental atelectasis |
linear densities at lung bases, usually parallel to diaphragm
in pts who are splinting (no deep breaths),
not due to bronchial obstruction; disappears over days |
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compressive atelectasis |
passive compression of lung due to poor inspiratory effort, large effusion, pneumothorax, or mass
no air bronchograms or shift of trachea/heart |
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obstructive atelectasis |
resorption of air from alveoli distal to an obstructing lesion of bronchial tree
visceral & parietal pleura remain in contact; mobile structures pulled toward atelectasis |
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What causes cardiogenic pulmonary edema? |
from increased hydrostatic pulmonary cap. pressure |
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causes of noncardiogenic pulmonary edema |
increased cap. permeability (ARDS), volume overload, malignancy, heroin, high altitude |
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signs of cardiogenic pulmonary edema |
cephalization of pulm. vessels, Kerly B/septal lines, peribronchial cuffing, fluid in fissures, pleural effusions (bilat), "bat wing" or butterfly pattern, patchy air bronchograms, cardiomegaly |
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What does cephalization of the pulmonary vessels look like? |
upper lobe vessels become distended
seen in cardiogenic pulm. edema |
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What are Kerly B/septal lines? |
fluid in interlobar septa; causes short white lines at lung bases perpendicular to & meeting pleural surface at lat. aspect of lung
seen in cardiogenic pulm. edema |
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What is peribronchial cuffing? |
thick bronchial walls due to fluid; look "ring-like" when seen on end, like little doughnuts |
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Signs of noncardiogenic pulmonary edema (vs. cardiogenic pulm. edema) |
less likely to have effusions, Kerley B lines,
more likely to have normal sized heart |
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pneumonia |
airspace disease & consolidation; airspaces filled w/ bacteria, microbes, pus
not assoc. w/ volume loss (diff. from atelectasis);
caused by bacteria, viruses, mycoplasma, fungi |
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When might pneumonia be sharply defined? |
when against a pleural surface |
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lobar (pneumococcal) pneumonia |
homogenous, in all/most of lobe, air bronchograms centrally, silhouette sign |
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segmental (staph) pneumonia |
multifocal, patchy, no air bronchograms |
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interstitial (viral, pneumocystic, mycoplasma) pneumonia |
involves airways walls, fine reticular pattern in lungs |
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aspiration pneumonia |
in most dependent portion of lung at time of aspiration;
usually lower lobes or post. seg of upper lobes; right more than left |
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primary vs reactivated TB |
primary: lower lobes, airspace disease, unilat. hilar adenopathy, pleural effusions, no cavitation
reactivated: upper lobes, bilateral, cavitation |
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signs present w/ pulmonary embolus (...but CXR most commonly normal) |
Westermark's (oligemia distal to PE);
big hilum (thrombus impaction);
atelectasis, linear/disc-shaped densities, pleural effusion, consolidation
Hampton's hump (rounded opacity) |
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to make a definitive diagnosis of pneumothorax, you must... |
be able to identify the visceral pleural line
(convex curve that parallels chest wall; no lung markings distal to line) |
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pneumomediastinum |
linear, streak-like lucency w/ thin white line paralleling left heart border
may also see air outlining great vessels, or parallel to spine in upper thorax, extending into neck |
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pneumomediastinum vs pneumopericardium |
pneumomediastinum extends higher than root of great vessels (aorta), pneumopericardium does not |
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subcutaneous emphysema |
air in soft tissue of neck, chest, abd walls;
air dissects along muscle bundles -> comblike striated appearance |
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best radiographic predictors of emphysema? |
hyperinflation (diaphragm flattening, etc) & bullae (air lesions w/o vessels)
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hiatal hernia |
stomach slips through esophageal hiatus into chest
see "air-filled mass" behind the heart |
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causes of hilar adenopathy |
inflammation (sarcoidosis, silicosis), neoplasm, infection (TB, histoplasmosis, mono) |
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ideal position for endotracheal tube |
midtrachea, 3-5 cm above carina; about 1/2 distance between medial ends of clavicles and the carina
(min. safe distance from carina is 2 cm) |
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rib fractures: how common? |
ribs 1-3: uncommon; need high force ribs 4-9: common; worry about PTX ribs 10-12: trauma to liver/spleen?
if 2 fxs in 3+ contiguous ribs (flail chest) |
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pulmonary contusion |
hemorrhage into lung, usually w/i 6 hr after trauma;
in periphery at point of max impact;
no air bronchogram b/c blood fills both
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sternum fracture |
due to direct trauma (e.g. MVA, CPR)
usually only visible w/ lat. view; CXR needed to r/o other injuries |
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What is a "coned lumbosacral view"? |
centered at level of lumbosacral junction;
helpful to assess low lumbar spine levels; usually included in an LS spine series |
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What's the exception to disc spaces gradually increasing in height from sup. to inf.? |
L5/S1 space is slightly narrower than L4/L5 |
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thoracolumbar spine injury classification |
1 column: ant. compression or isolated spinous process injury 2 column: burst injury 3 column: flexion-distraction, Chance-type |
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1 column thoracolumbar spine injury |
hyperflexion w/ compression; stable, BUT greater compression = greater risk of middle column involvement
plain x-ray may underestimate extent, consider CT |
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2 column thoracolumbar spine injury |
high force vertical compression; post. displacement of vert. body fragments into spinal canal -> high risk of cord/root damage
best seen on lat view (on AP, sudden widening of distance between pedicles at fx level) |
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3 column thoracolumbar spine injury |
aka Chance-type fx; flexion-distraction (high force deceleration); most common at thoracolumbar junction
unstable; high risk of neuro/organ injury
usually see compression fx of vert. body w/ transverse fxs of post. elements; increased interspinous distance |
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Why might you not see a fracture in the anterior column of a 3 column thoracolumbar spine injury (aka Chance-type fx)? |
the fx line may pass through the disc rather than the vertebral body |
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3 column thoracolumbar spine injury on AP view? |
an "empty" vertebral body (no post. elements);
increase in interspinous distance, break in continuity |
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transverse process fx |
often not visible on x-ray; consider CT
assoc. w/ injury to kidney |
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osteoporotic fx patterns |
"wedge" injuries & "biconcave" fxs
vertebral bodies are blacker |
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osteoporotic wedge compression fx |
lose height anteriorly w/ increased kyphosis |
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osteoporotic biconcave fx |
compression of both sup. & inf. endplates of vertebral body; loss of ht anteriorly |
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spondylolysis |
fx from inf. facet to sup. facet; acute or chronic; on oblique view most common = athletes at L5 ("scotty dog")
if bilat, leads to spondylolisthesis |
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spondylolisthesis on x-ray |
anterior slippage of vert. column (relative to inf. vertebra)
usually from bilat. spondylolysis; most common at L4-5 or L5-S1
Grade I = displacement up to 25% Grade II = displacement 25-50% |
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S/Sx of spondylolisthesis |
may be asymptomatic;
if severe, may cause foraminal stenosis -> nerve root impingement (Tx surgically) |
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manifestations of metastatis to spine |
moth-eaten appearance, ivory vertebra in lumbar spine, destruction of pedicle |
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abdominal aortic aneurysm on xray |
calcified aorta |
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sacral-iliac joints |
wide in adolescents, but only 2-4 mm in adults
increase suggests disruption (diastasis) |
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"Abdominal series" includes... |
supine & upright AP views & upright CXR
main view is KUB (kidney, ureter, bladder) |
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On prone view of abdomen, gas would rise to... |
the rectum & sigmoid
(then, to the ascending & descending colon) |
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examples of pleural effusions due to an intra-abdominal process? |
pancreatitis = left pleural effusion
ovarian tumor = R-sided or bilat. effusions
abscess below hemidiaphragm = ipsilateral effusion |
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define distention vs dilatation of the bowel |
distention: loop w/ enough air to fill the lumen completely; normal
dilatation: loop filled beyond normal size; abnormal |
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Reasons why there might not be air in the stomach... |
recently vomited; nasogastric tube w/ suction; stomach is fluid-filled |
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Air in a normal stomach |
in left upper quadrant (lowest part of stomach crosses midline)
1/2 way between abd wall & spine; could be displaced by splenomegaly |
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normal small bowel |
some air in 2-3 loops, non-dilated (<2.5 cm diameter); central in abdomen; has valvulae conniventes/plicae circularis
(max diam = 5 cm) |
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cecum |
if visible, often widest segment; usually in right iliac fossa |
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large vs small bowel markings |
large: haustra, do not extend to opposite wall, more widely spaced
small: valvulae, narrowly spaced |
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phleboliths |
small rounded calcifications (are calcified venous thrombi);
occur w/ increasing age, most often in pelvic veins of women;
have lucent center (diff. from ureteral calculi) |
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spleen |
usually doesn't go below 12th post. rib; about as large as left kidney
suspect enlargement if visible below this pt, or is displaces stomach bubble toward midline |
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kidney |
visible if there's peri-renal fat; length = ~4 lumber vert. bodies (10-14 cm)
enlargement only seen by displaced bowel gas |
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urinary bladder |
visible if surrounded by fat; distended = small cantaloupe contracted = lemon
enlrg -> displaces bowel out of pelvis (more common in men) |
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psoas muscle |
may be visible if extra-peritoneal fat;
inability to see is NOT reliable indicator of retroperitoneal disease |
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free gas in the peritoneal cavity |
bowel perforation (Dx on upright CXR after being upright for >10 min), surgical emergency
... or gas from laparoscopy |
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visualization of falciform ligament |
runs over ant. free edge of liver, to the right of upper lumbar spine normally not seen
free air w/ pt. supine will make it visible |
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most common causes of small bowel obstruction |
adhesions from abdominal surgery, hernias, tumors, Crohn's disease |
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smell bowel obstruction on xray |
dilatation >3 cm (longer segments more likely);
loops may stack on each other
valvulae conniventes (confirming sm. bowel) |
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ileus |
1+ bowel loops lose ability to propagate peristalsis
usually due to local irritation/inflammation, causes "functional" obstruction |
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localized vs. generalized ileus |
localized (aka sentinel loops): affects only 1 or 2 loops; usually small bowel
generalized: affects all loops of lg & sm. bowel, & freq. the stomach |
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common causes of large bowel obstruction |
colorectal carcinoma, diverticular strictures
less common: hernias, volvulus |
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when is dilatation of large bowel considered abnormal? |
cecum >9 cm rest of colon >6 cm |
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sigmoid volvulus |
more common than cecum; in older men
very large; line points from LLQ to RUQ, looks like coffee bean |
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cecal volvulus |
moves across midline into LUQ, forms line that points from RLQ to LUQ |
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bones as landmarks: how to find ureters? |
they follow the transverse processes |
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bones as landmarks: how to find ureterovesical junction (UVJ)? |
is at level of ischial spine |
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rimlike calcifications |
calcification in wall of hollow viscus
ex: cysts, aneurysms, gallbladder, urinary bladder (saccular organs) |
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linear or tracklike calcifications |
calcification in walls of tubular structure
ex: arteries, tubular structures
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lamellar or laminar calcifications |
calcification around a nidus inside a hollow lumen (e.g. gallbladder, urinary bladder)
usually called stones/calculi
xrays only ~50-60% sensitive for kidneystones |
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cloudlike, amorphous, or popcorn calcification |
formed inside of a solid organ/tumor
ex: body of pancreas (chronic pancreatitis); leiomyomas (fibroids) of uterus; lymph nodes (ex. old TB); soft tissue (prior trauma; crystal salts) |
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bones in the human skeleton |
206 total
long: femur short: carpals, tarsals flat: parietal, frontal sesamoid: patella, great toe irregular: vertebrae, sacrum, coccyx |
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metaphysis |
zone adjacent to growth plate on the diaphyseal side |
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apophysis |
normal outgrowth of bone, fuses in later development
usually doesn't form articulation, but can form insertion point for tendon/ligament |
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bayonet apposition |
overlap of fx fragments causing shortening of the bone length |
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distraction |
longitudinal separation (widening) of fracture fragments |
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impaction |
shortening of bone w/o loss of alignment; bone of one portion is driven into the other |
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most common cause of pathological fractures? |
osteoporosis
(other: tumors) |
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stress fracture |
repetitive low impact trauma; no visible fx line, but see a periosteal reaction (raised calcification of the periosteum) |
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subluxation |
incomplete dislocation; 2 bones still have partial contact w/ each other |
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diastasis |
separation of 2 normally adjacent bone parts, either at ligamentous joint or growth plate
e.g. pubic symphysis, SI joint |
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fracture mimics |
unfused growth plate, unfused apophysis, accessory ossicles, vasculature/nutrient lines, Harris lines (run transverse; developmental) |
