imaging final Flashcards
indications for imaging lumbar spine
trauma
pain radiating to legs
limitation in motion
planned or prior surgery
eval of primary/secondary malignancies
arthritis
osteoporosis
compression fractures
eval of kyphosis and scoliosis
suspected congenital anomalies and syndromes
eval of spinal abnormality seen on other imaging
follow-up of known abnormality
suspected spinal instability
lumbar spine projections
AP
lateral
right and left oblique
coned lateral view of lumbosacral articulation
right and left posterior oblique (Lspine)
right side structures on RPO
left side on LPO
posterior shows downside facet joints closest to image receptor
anterior oblique (Lspine)
shows upside facet joints farther from image receptor
R and L obliques need what to distinguish them
marker to determine left or right
scottie dog of oblique L-spine
nose - transverse process
eye - pedicle
ear - superior articular facet
foreleg - inferior articular facet
body - lamina and spinous process
tail - superior articular facet of opposite side
hind leg - inferior articular process of opposite side
what is best choice for imaging trauma at lumbar?
CT
TAP body scan
when is MRI indicated/not indicated in trauma at Lspine
in - if neural compromise
not - if CT is normal
predominate site for L spine vertebral fractures
thoracolumbar junction (T11-L2)
because they are transitional from fixed thoracic to mobile lumbar
spondylosis: definition and 3 causes
defect at pars interarticularis
congenial
traumatic
stress fracture by chronic strain (most common)
spondylolisthesis
forward displacement of vertebra on the one beneath it
retrolisthesis
posterior displacement on the one beneath it
incidence of spondylolisthesis
~5-10% of people
children and adolescents typically affected
lower lumbar levels most often involved - L4-L5 L5-S1
spondlylolisthesis can be the consequence of:
spondylolysis
spondlylolisthesis can result from:
congenital or developmental aberrations
pathological processes
degenerative changes
clinical presentation of spondlylolisthesis
pain after athletic activities
lumbar flexion reduces pain
palpation of SPs can reveal rotation of depression
SP sign correlated with radiologic findings to determine type
degenerative spondlylolisthesis
entire vertebra slips forward as a unit
~step off of Sp is below level of slip
fracture spondlylolisthesis
forward slip of vertebral body, pedicles, and superior articular processes
inferior processes, laminae and SPs remain in normal position
~step off is above level of slip
treatment of spondlylolisthesis
restriction of extension loads
flexion can be self-reducing and relieve pain
bracing
surgical fusion in cases of neurological compromise or persistent pain that does not respond to conservative
degenerative pathologies associated with lumbar spine
spinal stenosis
IVD herniations
DDD radiologic findings
decres disk space height
osteophytes at vertebral endplates
schmorl’s nodes
vacuum phenomenon
DJD radiologic findings
decres z joint space
sclerosis
osteophytosis at joint margins
spondylosis radiologic findings
osteophytes visible as readiodense irregularities at vertebral joint margins
spondylosis deformans radiologic findings
claw like spurs cupping towards IVD at more than one level
DISH radiologic findings
flowing ossification of at least four contiguous vertebrae
preservation of disk height and absence of DDD
absence of sacroiliitis or z joint DJD
lumbar stenosis
narrowing of spinal canal secondary to ST or bone enlargement
classification of lumbar stenosis
congenital
acquired
by anatomic region involved
congenital lumbar stenosis
achondroplasia
morquio’s syndrome
down’s
idiopathic stenosis
acquired lumbar stenosis
prior surgery
spondylolisthesis
infection
tumor
spinal deformity secondary to trauma
bulging og annulus
herniation of IVD posteriolaterally
PLL thickening
PLL ossification
hypertrophy of z joints
DJD of z joints
hypertrophy of ligamentum flavum
epidural fat deposition
spondylosis of vertebral joint margins
uncovertebral joint hypertrophy
metabolic/endocrine disorders
3 anatomical classifications of lumbar stenosis
central spinal canal
invertebral foramen
subarticular or lateral recesses
incidence of lumbar stenosis
1/4 of asymptomatic population under 40
most over 60 have some degree
symptomatic affects men > women 40-50 yo
central canal narrowing most prevalent at L4
etiology of degenerative stenosis
osteophytes at joint margins
bony hypertrophy of pedicles, laminae and z joints
IVD bulging
displacement of entire vertebra
thickening of ligamenta flava
normal AP diameter of spinal canal in adult men
cervical spine C3-C5: 17-18 mm
c-spine C5-C5: 12-14mm
T-spine: 12-14mm
L-spine: 15-27mm
clinical presentation of spinal stenosis
severe cases result in disability
most serious complication is central cord syndrome
central cord syndrome
incomplete spinal cord lesion associated with hyperextension injuries and results in proportionately greater loss of motor function to upper extremities than lower extremities with variable sensory sparing
cervical spine stenosis presents with
long tract and radicular signs
headaches
pain
radiating electric-like shock sensations elicited with cervical spine flexion
concurrent cervical and lumbar spinal stenosis can present with
gait disturbance
myelopathy
radiculopathy
lumbar spine stenosis presents with
diffuse unilateral or bilateral LBP and/or LE pain
numbness
weakness
simian stance
posture of trunk, hip and knee flexion
neurogenic claudication:
congestion of blood vessels at stenotic level
exacerbated by standing and spinal extension
vascular claudication
exacerbated by exercise and improved with standing
disk herniation differentiated clinically by aggravating factors:
pain by sitting, flexion, lifting, valsalva
relieved by walking
pain from spinal stenosis not affected by any of those maneuvers and aggravated with walking
diagnosis of pts with lumbar spinal stenosis
age 60-70 - 2
> 70 - 3
symptoms present > 6 months - 1
symptoms improve when bending forward - 2
symptoms improve when bending backward - -2
symptoms exacerbated while standing up - 2
intermittent claudication (+) - 1
urinary incontinence - 1
clinical bottom line for LSS
> 7 indicates a small meaningful shift in probability
< 2 indicated moderate shift that does not have LSS
what images significant for finding spinal stenosis?
conventional radiographs significant for exclusion or assessment
advanced imaging in lumbar spine
CT - spinal stenosis
myelography - constriction of thecal sac
MRI - assessment of thecal sac and contents
SPECT - discriminating stenosis from medical disease, infections, tumors
treatment of stenosis
analgesic medications
NSAIDs
epidural steroid injections
PT for strengthening and flexibility exercises
IVD herniations
defined as extension of NP through AF and beyond adjacent vertebral margins
incidence of IVDH
most common in 25-45 yo
men > women
predominance in smokers, obsese, exposure to vehicular vibration
most common at lumbar spine - 90% at L4-L5
rare in thoracic spine
cervical IVDH occur at 90% frequency at C5-C6
clinical presentation of IVDH
cause LBP and referred or radicular pain
exacerbated with flexion, sitting and valsalva
nerve root pressure = loss of muscle strength
rarely cauda equina syndrome can develop - emergency
history and physical examination data of cauda equina syndrome
urine retention
fecal incontinence
saddle anesthesia
sensory or motor deficits in the feet
radiologic findings of IVDH
unnecessary in first 4-6 weeks
20-30% are asymptomatic
many improve with conservative treatment in 4-6 weeks
imaging when conservative treatment fails
exceptions are CES
advanced imaging for IVDH
myelography
CT myelography
diskography
CT
MRI
treatment for IVDH
conservative measures
~PT
~analgesics
~short term bedrest
~restricted activities
only small percentage require surgery
radiographic hallmarks at DJD at SI joint
decreased joint space
subchondral sclerosis
osteophyte formation at joint margins
only lower halves of joint space image represent synovial portion of joints
thus evaluation of DJD confined to lower half of joint space
ankylosing spondylitis
inflammatory arthritis characterized by joint sclerosis and ligamentous ossification
manifests first in stiffness of SIJ and extends to L and T
prevalence of ank spon
men affected seven times more than women
onset in 20s
early diag by blood work
radiologic findings of ank spon
abnormal narrowing of upper half of SIJs
squaring-off of anterior borders of vertebral bodies
later, syndesmophytes form bridging vertebral bodies
known as bamboo spine
indications of hip radiologic examination
trauma
osseous changes secondary to metabolic disease
systemic disease or nutritional deficiencies
neoplasms
infections
arthropathies
preoperative, postoperative, follow up studies
congenital syndromes and developmental disorders
vascular lesions
evaluation of soft tissue
pain
correlation of abnormal skeletal findings on other imaging
recommended projections of hip
AP and lateral
what is osseous pelvis evaluated with?
AP projection
iliopectineal/iliopubic line
represents anterior column
line from sciatic notch to pubic tubercle
ilioischial line
represents posterior column
line from iliac notch to inner surface of ischium representing posteromedial margin of quadrilateral surface of iliac bone
intersects teardrop
anterior lip of ace
represents anterior wall of ace
posterior lip of ace
represents posterior wall of ace
acetabular roof
represents superior cortical aspect of ace cup
corresponds to major weight-bearing portion of ace
anterior ace rim
represents anterior margins of ace cup
posterior ace rim
represents posterior cortical rim of ace cup
radiographic teardrop
seem on medial ace formed by cortical surfaces of pubic bone and ischium representing anteroinferior ace
klein’s line
drawn along lateral femoral neck intersecting the femoral head bilaterally
shenton’s hip line
should be possible to draw smooth curve along medial and superior surface of ob foramen to medial aspect of femoral neck
iliofemoral line
smooth curve along outer surface of ilium that extends inferiorly along femoral neck
femoral neck angle (angle of inclination)
intersection of line drawn through center of femoral shaft and line drawn through center of femoral neck
normal 130
coxa vara <130
coxa valga >130
DJD of hip
aka osteoarthritis
most common disease in the hip
primary and secondary of DJD at hip
pri: developing without a clear precursor
sec: directly related to trauma or pathology
secondary DJD caused by:
fracture
paget’s disease
epiphyseal disorders
congenital dislocation
AVN
other inflammatory arthritides
clinical presentation of DJD in hip
progressive pain and loss of ROM
impaired ambulation
radiologic findings of DJD at hip
joint space narrowing
sclerotic subchondral bone
osteophyte formation at joint margins
cyst or pseudocyst formation
migration of femoral head
what do cysts result from
degeneration of articular cartilage
loss of buffering effect results in microfractures
intrusion of synovial fluid into bone
show up as radiolucent lesions
what are cysts in acetabulum called?
egger’s cysts
most common pattern of altered surface when femoral head migrates in DJD
superomedial to normal position
treatment of DJD is designed with goals of:
decres pain
restoring flexibility and strength
reserving functional activities and amb with ADs to unload joint from full weight-bearing stresses
surgical treatment of DJD
wedge osteotomy
femoral head and neck resection
hemiarthroplasty to replace fem head
total arthroplasty
hip resurfacing - young with goo bone density
hip resurfacing
metal coating cemented over femoral head and metal liner impacted into ace
liner has coating to promote ingrowth of bone too further stabilize it
rheumatoid arthritis of hip
progressive, systemic, autoimmune disease
3X more in women
onset most common in young adulthood
clinical presentation of RA in hip
morning joint stiffness
bilateral and symmetrical swelling of joints
pain and functional disability
rheumatoid nodules
positive rheumatoid factor test
radiographic changes consistent with RA
radiologic findings of RA in hip
osteoporosis of periarticular areas
symmetrical and concentric joint space narrowing
articular erosions
synovial cysts
periarticular swelling and joint effusions
axial migration of femoral head
acetabular protrusion
where is osteoporosis first seen in hip?
femoral head
what causes acetabular protrusion
concentric joint space narrowing promotes axial migration of femoral head into acetabulum
best projection for synovial cysts
MRI
distinct difference between DJD and RA in hip
RA has minimal or absent reparative process
sclerotic subcondral bone and osteophyte formation are not features of RA
RA deformities
boutonniere deformity
swan neck deformity
OA deformities
heberden’s node
bouchard’s node
pharmacological treatments for RA
NSAIDs
coricosteroids
gold salts
immunosuppressive drugs
conservative treatment for pain and disability for RA
rehab focuses on pain modalities, splinting, adaptive functional and amb devices, and exercise to promote strength/ROM to minimize deformity
surgical treatment for RA
total arthroplasty
AVN of femur
interruption of blood supply to femoral head causing bone tissue death
osteochondritis dissecans: local segment of bone
epiphyseal ischemic necrosis: affects entire epiphysis in growing child
where is most common location for epiphyseal ischemic necrosis?
proximal femur
three categories of AVN
compression or disruption
blood vessel occlusion
blood vessel blockage
causes of epiphyseal ischemic necrosis at femoral head
called legg-calve-perthes disease
seen in young boys around 6 yo
idiopathic AVN
clinical presentation of LCP
synovitis or inflammatory response of hip joint
non-specific dull pain in joint, thigh, leg
adults exhibit limited joint motion and progressive painful limp
children exhibit painless, slowly evolving limp
~waddling type gait
radiologic findings of LCP
appear normal for several weeks
one of first signs: radiolucent crescent
crescent parallel to superior rim of femoral head subjacent to articular surface
what are characteristic signs of initial necrotic processes?
sclerosis and cyst formation at femoral head
radiographic findings of advanced AVN?
femoral head collapses or appears flattened
entire femoral head becomes more radio-dense
at advanced stage, joint is compromised
what do radionuclide bone scans identify?
increased uptake at sit of lesion soon after injury
what is the most appropriate study for early diagnosing AVN?
MRI
when is conservative treatment of AVN most successful? (hip)
in younger pts.
they possess healthier, more adaptable blood supply
how to revascularize AVN with conservative treatment? (hip)
prolonged avoidance of weight bearing
traction
bracing
casting
exercise
surgical treatment of AVN at hip
drilling into femoral head to quicken revas
grafting healthy bone into drill hole to assist repair
varus derotation osetotomy
last resort - joint replacement
ottawa knee rules
age greater than or equal to 55
isolated patella tenderness
tenderness at head of fibula
inability to bear weight immediately after
pittsburgh knee rules
fall or blunt trauma
age <12 or >50 - immediate yes
not able to walk four weight bearing steps
which knee rules more specific
pittsburgh
images ordered at knee if
joint effusion after blow
inability to walk without limping
palpable tenderness over patella or fibular head
inability to flex to 90
isolated meniscal tears present with
intermittent clicking and eventually blocking of motion
effusion
pain
how are menisci seen on MRI?
low intensity
tears are high intensty
most common meniscal tear
vertical
bucket tear (meniscus)
longitudinal extension of vertical tear
meniscal tears in older pop
usually horizontally oriented
clinical presentation of tear of collateral ligs
pain
joint effusion
instability
LCL MOI
varus force
MCL MOI
valgus force
associated with medial meniscus tear
O’Donoghue’s terrible triad
MCL
med meniscus
ACL
most revealing image for knee ligaments
T2 MRI
how do ligs look on T2 MRI
low intensity
abrupt discontinuity would show lig tear
tears of cruciate ligs (women vs men)
women affected 8x more than men in same activities
PCL MOI
external forces that strike anterior aspect of knee
ACL MOI
non-contact forces that place great valgus and rotary stresses on knee
hears pop of rupture
best image for cruciate ligs
sagittal MRI
what is the most frequently injured joint?
ankle
only small percentage actually have a fracture
ottawa ankle rules
unable to bear weight
point tenderness in malleolar zone, mid-foot, base of fifth MT, or navicular
100% sensitive
adavanced imaging for ankle when:
plain insufficient to guide treatment
after radio findings are neg when further injury suspected
what percentage of all ankle sprains are inversion?
85%
larger mag inversion sprains associated with:
lig rupture or avulsion
ankle instability
functional impairment
what ligs do inversion stresses sprain?
LCL
anterior tibfib
calcaneofib
without bony involvement
spectrum of injuries from inversion stresses
LCL sprain
LCL rupture
transverse fracture of lateral malleolus
fracture of med mall with rupture of LCL
eversion sprains
stress MCL
associated with bony damage
spectrum of injuries from eversion stresses
MCL sprain
MCL rupture
med mall fracture
lat mal fracture with MCL rupture
other structures that sever sprains can disrupt
avulsion fractures pull ligs at attachments
tearing of dis tibfib syndesmotic complex
instability- tearing ligs
when is radio image needed in ankle
fracture is suspected
maisonneuve fracture
insterosseous membrane involved and sprial fracture at prox fib
treatment of ankle sprain
restore stability
ankle fractures are in combo with:
lig rupture
avulsions
other fractures
ankel fracture MOI
axial or rotational loading
factors determining injury pattern in ankle fracture
instability
age
bone density
comorbidity to ST
position of foot at time of loading
mag, direction, rate of loading
unimalleolar
indicating fracture of either lat or mad malleolus
bimalleolar
fracture of both lat and med mall
trimalleolar
both malleoli and post tib
how to image stress fractures
MRI
treatment of ankle fractures
stabilize
immobilize or surgery
complications of ankle fractures
non-union or degen joint changes
frequency of talar fractures
second to calcaneal
MOI of talar fractures
dorsiflexed foot
ex. slam on breaks in collision
interarticular fractures
almost all because 3/5 of talus covered art cart
radio eval of talus fracture
plain films good most of the time
CT or MRI with plain neg or pre-op
treatment of talus fracture
non-op - short leg cast for 8-12 weeks, NWB 6 weeks
op - often ORIF
complications of talus fracture
post traumatic arthritis of ankle and subtalar
bad blood supply because no muscle attach to it
predisposed to AVN
osteochondral defect
focal areas of articular damage and injury of adjacent subchondral bone
osteochondritis dissecans
dur to repeated microtrauma
result of aseptic separation of osetochondral fragment
2:1 male to female ratio
location of osteochondral defect
femoral condyle
humeral head
talus
capitulum of humerus
clinical presentation osteochondritis dissecans
asymptomatic to sig pain and locking
joint effusion and synovitis present
treatment of osteochondritis dissecans
spontaneous healing unless there is an unstable fragment
results are only fair
accessory bones in foot
form due to failure of ossification centers
30% of adults
not always symmetrical
increased density
describe protection and stability of shoulder
less mechanical protection and less bony stability than any other large joint
MRI for acute shoulder pain when?
initial radiographs normal
RC pathology, instability or labral tears suspected
when is shoulder CT recommended?
if MRI unavailable or contraindicated
RC MOI
GH dislocation
FOOSH
forceful abduction of arm
impingement
most common RC tear
involves hypovascular critical zone in supraspinatus 1 cm above insertion
predictor variables for impingement syndrome
positive hawkins-kennedy impingement sign
positive painful arc sign
positive infraspinatus muscle strength test
predictor variables for full thickness RC tear
positive painful arc sign
positive infraspinatus muscle strength test
positive drop arm test
past radio eval of RC tears
arthrography
intact- contrast confined to joint capsule
complete tear- contrast travels up to bursa
present radio eval of RC tears
MRI - more info and noninvasive
US
changes secondary to RC tears
irregularity of greater tuberosity
narrowing of distance between acromion and hum head
erosion of inferior aspect of acromion
conservative treatment if RC tears
rest
NSAIDs
cortison injections
most need surgery
complications of RC tear
degen changes at GH and AC
failure to regain full ROM and strength following surgery
SICK scapula
scapular malposition
inferior medial border
coracoid pain and malposition
dyskinesis of scapula
SICK scapula symptoms
postero-superior scapular pain
anterior shoulder pain
proximal shoulder pain
c spine pain
TOS
three types of dyskinesis
1: inferior medial scapular prominence
2: medial scapular border prominence
3: superomedial border prominence
which types of dyskinesis associated with SLAP lesions
1 and 2
which type of dyskinesis associated with impingement and RC lesions
3
two basic functions of labrum
deepen glenoid fossa
attachment points for ligaments and biceps tendon
symptoms of labral tear
pain with overhead movements
clicking or catching
instability
MOI of labral tear
dislocation
forceful lifting
FOOSH
repetitive movements
most appropriate procedure to assess instability and labral tears
MR arthrography
CT arthrogrphy is second choice
treatment of labral tears
most heal conservatively because of rich oxygen supply
what labral tears require surgery
avulsions to glenoid rim
debride minor tears
biceps tenodesis - changes insertion of biceps
silhouette sign
loss of normal interference between air and ST
can localize lesion to a specific lobe of lung
cardiothoracic ratio
estimate of heart size
in adults, width of heart should be less than half of width of chest at level of diaphragm
mediastinum
space between lungs
hilum (lung root)
where bronchi, arteries, veins, and nerves enter and exit lungs
diaphragm
separates abdominal cavity from thoracic cavity
seen at 10th intercostal space
costophrenic angles
sharply pointed downward indentations between each hemidiaphragm and adjacent chest wall
routine chest exam
erect PA
erect left lateral during full inspiration
PA chest
view from apices down to costophrenic angles
lateral chest
from sternum anteriorly to posterior ribs
diagnostic categories
lung field abnormally white
lung field abnormally black
mediastinum abnormally wide
heart abnormally shaped
when is lung field abnormally white
pneumonia
water density consolidation
silhouette sign
air bronchogram signs
when is lung field abnormally black
pneumothorax
common following penetrating chest wounds
affected lung field appear black
deep sulcus sign
mediastinal shift from radiolucent lung field
when is mediastinum abnormally wide
aortic dissection - tear in inner layer of aorta
most common site in ascending aorta
other signs of aortic dissection
obliteration of normal arch shape
downward slant of left main bronchus
tracheal deviation to right
when is heart abnormally shaped
congestive heart failure
vascular redistribution
kerley b lines
peribronchial cuffing
pleural effusion
bat wing or butterfly pattern
