Shoulder Girdle and Humerus Flashcards
why use grids?
minimize scatter radiation
used when body part Is thicker than 10cm
used with higher kVp
Markers
on correct side of body
lateral aspect
int the beam not obstructing anatomy
patient face up - marker face up
patient face down - marker face down
what are compensating filters?
even out the density of the anatomy
- improve image quality
- may reduce radiation exposure
know how to position filters, and when
won’t use filters at Fanshawe, but maybe at placement
Filter placement
thickest part of filter corresponds with thinnest part of anatomy
collimator mounted and contact
What placement of a filter could decrease skin entrance exposure to the patient?
collimator mounted
What do you usually see on humeral and shoulder girdle images?
fractures
dislocations
arthritis
bone cysts/neoplasms
- usually located proximal humerus or distal knee)
What are the humerus views?
AP
Lateral
Transthoracic lateral
Humerus - AP projection
humerus true AP position
CR - perpendicular
CP - middle of humerus, may angle collimator
suspend respiration
Humerus - AP evaluation criteria
Both joints on image
no rotation
humeral head and greater tuberosity in profile
lesser tubercle between head and greater tubercle
use a practice breath when positioning to ensure you are not clipping any anatomy when they hold breath
Humerus - lateromedial
RPO
back of hand on hip
CR - perpendicular
CP - middle of humerus
- include 5cm/2” above/below humerus
Suspend respiration
epicondyles need to be stacked on top of each other
Humerus - Mediolateral
LAO
Arm and hand in same position as lateromedial
patient facing bucky
marker face down
Humerus - lateral projection evaluation criteria
both joints on image
superimposed epicondyles
lesser tubercle in profile
greater tubercle superimposed with head
Humerus - transthoracic lateral projection
injured humerus against bucky
raise remote arm above head
include all the humerus
use breathing technique - say act like breathing through a straw to ensure no shoulder movement
Humerus - transthoracic evaluation criteria
entire humerus on image
scapula, clavicle and humerus seen through lung field
breathing technique will blur ribs
increase time and decrease mA
What are the shoulder projections?
AP - internal, external and neutral rotation
Inferosuperior axial
Superoinferior axial
PA/AP oblique - scapular Y
AP oblique
Shoulder - AP projections
arm hanging by side - external (true anatomical position), nuetral (oblique, hand to side) and internal (same position as lateromedial humerus)
CP - 2.5cm inferior to coacoid
suspend respiration
Shoulder - external, neutral and interior series
entire shoulder girdle for the first image
- full collar bone, apex of scapula and above shoulder
Shows the rotation of humeral head
tighten the collimation after the first image
Shoulder - AP evaluation criteria
entire scapula, clavicle, proximal humerus
external - head and greater tubercle in profile
neutral - greater tubercle partially superimposing head
internal - lesser tubercle in profile
Shoulder - Glenoid Fossa (AP Oblique) projection
RPO
patient rotated 35-45 degrees to injured side
CP - 5cm/2” medial, 5cm inferior to superolateral border of shoulder
feel for spine of scapula - rotate until it is flat against the IR
glenoid cavity in profile
open scapulohumeral joint
Shoulder - transthoracic lateral projection
same as position for humerus
breathing technique
Shoulder - transthoracic lateral evaluation criteria
scapula, clavicle and proximal humerus send through the lung field
Shoulder - inferosuperior axial projection
marker face up
Use CR cassette crosswise
patient supine with arm abducted - hand supine
CR - horizontal with 15-30 degree angle - more abduction, more angle
CP - exit at acromion
detector and CR same angle
as close as you can get within reason
Shoulder - inferosuperior axial evaluation criteria
scapulohumeral joint with some overlap
coracoid process anterior above the clavicle
lesser tubercle in profile anteriorly
AC joint projected through humerus
Shoulder - Rafert Modification
looks for a Hills-Sachs defect
external rotation of arm - inferosuperior position with thumb down
CR about 15 degrees medially, exiting acromion
Shoulder - superoinferior axial projection
patient leans, shoulder over table - make sure back is straight
CR - 5-15 degrees laterally
CP - glenohumeral joint
Suspend respiration
angle from acromion to armpit
marker facedown
Shoulder - superoinferior axial evaluation criteria
coracoid process above clavicle
lesser tubercle in profile
AC joint through humeral head
Shoulder - PA Oblique - Lateral “Y Scap”
Rotate injured shoulder 45-60 degrees towards IR - feel for scapula
CP - midpoint of scapula
Marker face down
medial border of scapula and acromion need to be lined up
Shoulder - PA Oblique Evaluation criteria
No superimposition of scapular body over bony thorax
Lateral scapula
Humeral head and glenoid between coracoid and acromion
demonstrates anterior and posterior dislocations
Which shoulder dislocation is most common?
anterior
