skills Flashcards
what makes up the concentric arcs on a lateral elbow?
- medial trochlea
- trochlear sulcus
- capitulum
is the radial tuberosity in profile on a lateral elbow?
no
how do you know when the wrist has been pronated on a lateral elbow
when the radial tuberosity is in profile posteriorly.
how do you know when the wrist has been externally rotated on a lateral elbow?
the radial tuberosity is in profile anteriorly
how could you tell if the proximal humerus was too elevated on a lateral elbow?
the radial head would be too posterior to the coronoid process and therefore the capitulum would be too distal to the trochlea
how could you tell if the proximal humerus was too depressed on a lateral elbow?
the radial head would be anterior to the coronoid process and the capitulum would be too proximal to the trochlea.
if the radial head is too distal to the coronoid on the lateral elbow, what is the positioning error?
the forearm was depressed, you have to raise the forearm.
if the radial head is too proximal to the coronoid process on a lateral elbow, what was the positioning error?
the forearm was too elevated, depress the forearm.
where is the greater tubercle and the humeral head seen on the humerus when the hand is supinated?
greater tubercle seen laterally, and humeral head medially
where will the lesser tubercle be demonstrated on a lateral humerus?
medially
will the anterior capitulum and medial trochlea be aligned on a lateral humerus?
no, nearly aligned.
where is the radial tuberosity seen when the hand has been externally rotated on a lateral elbow?
anteriorly
where is the radial tuberosity seen when the hand has been internally rotated on a lateral elbow?
posteriorly adjacent to the ulna.
how does a dislocated shoulder appear on an AP shoulder?
glenoid cavity is partially demonstrated with the humeral head inferior to the cavity.
where is the greater tubercle and humeral head seen when the arm is in neutral rotation?
partially in profile laterally and humeral head partially in profile medially.
what tubercle of the humerus is visualized when it is internally rotated, and where?
lesser tubercle visualized medially and humeral head superimposed by the greater tubercle.
how much should the body be obliqued for a grashey method shoulder?
35-45 degrees towards the affected shoulder
where will the coracoid process appear on a grashey method shoulder if there was anterior tilt?
inferior to the glenoid.
where will the coracoid process appear on a grashey method shoulder if there was posterior tilt?
superior to the glenoid.
how can you tell if the body has been over rotated on a grashey method shoulder vs underrotated?
the joint will be closed for both but:
overrotation = coracoid process more than 0.25” superimposed on humeral head
under rotation = corocoid process less than 0.25” superimposed over humeral head
where should the superior scapular angle be in relation to the clavicle on a PA scapular Y shoulder?
at the same transverse angle.
where do you center for an AP shoulder vs a AP scapula?
shoulder: 1” inferior to the coracoid process
scapula: 2” inferior to coracoid process
what makes a good foot AP oblique?
- tarsi sinus open
- 5th MT tuberosity in profile
- cuboid cuneiform joint open
- open 2-5 intermetatarsal joint spaces open
what tarsal bones joints should be open on an AP axial foot?
navicular cuneiform
should the tarsi sinus be visualized on a 45 degree oblique ankle?
yes
what happens when the distal lower leg is elevated on an AP ankle?
the talo-tibial joint is closed
are the knee and ankle joints closed in a tibfib AP and lateral?
yes sir
are the wrist and elbow joints closed in a forearm ap and lateral?
no
will the inferior sacrum be free of superimposition on an AP axial SI joints?
no, it will be superimposed by the symph pub.
what is the angling error if the inferior sacrum is not superimposed by the symph pub?
there was insufficient angling.
how much should the body be angled for an oblique SI joint view?
25-30 degrees
how do you adjust the cephalic angulation on an AP Cspine if the patient is kyphotic?
angle more to accommodate for the curve
what vertebral bodies should be visualized on an AP axial cspine?
C2-C7
what parts of the skull should be aligned when positioning for an AP cspine?
upper incisors with mastoid tip
where will the spinous processes be demonstrated on an AP cspine if the patient is turned toward their right side?
more toward the left
An image of an open mouth view demonstrated the right lateral mass with more space from the dens than the left side. which way was the patient turned? how would you correct this?
the patient was turned toward their right side.
turn the patients head more toward the left side.
does C1 have a spinous process?
no, it is a posterior arch.
why are lateral cspine hyperflexion and hyperextension views taken?
to evaluate mobility in the spine
on an RAO cspine view, which pedicle is in profile and where is the other one seen?
the Right pedicle is in profile, and the left one is on the anterior aspect of the vertebral body.
what is the centering point for a towne skull projection?
2 1/2 inches above glabella to pass through foramen magnum
how to assess for rotation on a skull townes view?
petrous ridges should be symmetrical
where are the dorsum sellae visualized if there was underangulation/insufficient head flexion?
superior to the foramen magnum
where are the dorsum sellae visualized if there was over angulation/too much head flexion?
foreshortening of dorsum sellae and will be superimposed on arch of C1
what view would best demonstrate le fort and tripod fractures?
waters facial bones
what view would you do for an orbital fracture (blowout)? and why?
modified waters.
orbital floors are perpendicular to IR, provides less distorted view of the orbital rims than a normal waters.
where will the petrous ridges lie in waters vs modified waters views?
waters: inferior to the maxillary sinuses
modified waters: in the lower half of the maxillary sinuses, below the IOMs
in an axiolateral mandible, if the head is in a true lateral, what structure of the mandible is being visualized?
the ramus
in an axiolateral mandible, if the head rotated 30 degrees toward the IR, what structure of the mandible is being visualized?
the body
in an axiolateral mandible, if the head rotated 45 degrees toward the IR, what structure of the mandible is being visualized?
the mentum
in an axiolateral mandible, if the head rotated 10-15 degrees toward the IR, what structure of the mandible is being visualized?
general survey.
is the side away or in contact with the IR being visualized on an axiolateral mandible?
close to IR
difference between the PA vs PA axial mandible projection
PA: CR perp and exits at lip junction
PA axial: CR 20-25 degrees cephalad and exits at acanthion
what is visualized on a PA mandible projection?
- lateral portion of the body
- mandibular rami
what is visualized on a PA axial mandible projection?
- TMJ region
- heads of condyles visible through the mastoid processes
- condyloid processes are well visualized and are slightly elongated
how much do you angle for a PA axial mandible vs an AP axial?
PA: 20-25 degrees cephalad
AP: 30-42 caudad
which sinuses are demonstrated in a lateral sinuses?
all four
which sinuses are demonstrated on a caldwell sinuses?
frontal and anterior ethmoid
can you use an angle on a sinus view?
no because it will distort the air-fluid levels if there are any.
which view best demonstrates the maxillary sinuses?
waters.
how much do you angle for an inlet view? and what does this view demonstrate?
40 caudad. demos the pelvic ring or inlet.
how much do you angle for an outlet view? and what does this view demonstrate?
20-35 for males
30-45 for females
demos superior and inferior rami of pubis and body, and ramus of ischium.
centering points for inlet vs outlet views?
inlet: midpoint at level of ASIS
outlet: 1-2 inches distal to the superior border of symph pub
which way do you angle if you are taking a mediolateral knee x-ray?
cephalically
how can you tell if you have used an excessive cephalic angle on a mediolateral knee?
the medial condyle will be more proximal to the lateral
which way do you angle the CR on a crosstable lateromedial knee x-ray?
caudad
how can you tell if you have used an insufficient caudad angle on a lateromedial knee?
the medial condyle will be distal to the lateral condyle
