Exam 4 - Shoulder Girdle & Bony Thorax Flashcards
the shoulder girdle is formed by which two bones?
scapula & clavicle
what is the function of the shoulder girdle?
connect upper limb to trunk
What kind of joint is the shoulder?
diarthrodial joint
what kind of bone is the clavicle?
long bone, doubly curved
are clavicles are longer, wider, thicker in males or females?
males
what is the function of the clavicle?
fulcrum for movements of the arm
what does the acromial extremity articulate with?
the acromion process of scapula
what does the sternal extremity articulate with?
the manubrium of sternum and 1st costal cartilage
what kind of bone is the scapula?
flat bone
what are the parts of the scapula?
2 surfaces
3 borders
3 angles
What are the 3 angles on the scapula?
superior (medial), inferior, lateral
what is the anterior surface of the scapula called and what does it include?
costal & subscapular fossa
what is the posterior surface of the scapula called and what does it include?
dorsal & its divided into superior and inferior portions by the spinous process
what is on the end of the spine of the scapula?
acromion
What border is by the spine of the scapula?
medial
what are the 3 borders of the scapula?
medial (vertebral)
lateral (axillary)
superior
what plane from the proximal humerus lay on?
horizontal oblique plane
what sides are the lesser and greater tubercles on?
lesser = anterior side
greater = lateral side
where do a lot of fractures happen on the humerus?
anatomical neck
what are the posterior greater tubercle muscle attachments?
superior:
middle:
inferior:
superior: supraspinatus
middle: infraspinatus
inferior: teres minor
what is the anterior lesser tubercle muscle attachment?
subscapularis
the long head tendon of the biceps brachii arises from:
superior margin of glenoid cavity
the short head tendon of the biceps brachii arises from:
coracoid process
where do the muscles of the biceps brachii insert?
into the radial tuberosity
what are the small synovial filled sacs that relieve pressure and reduce friction?
bursa
can you see calcifications of bursas on x-rays?
yes
how do you do the inferosuperior axial projection (lawrence method)?
supine position, CR horizontal, arm at about a 90 degree angle
what kind of joint is the scapulohumeral joint?
ball and socket
what kind of joint is the acromioclavicular joint?
gliding
what kind of joint is the sternoclavicular joint?
double gliding
what does an AP projection of the shoulder with external rotation show?
greater tubercle and humeral head in profile
supraspinatus tendon insertion visualized
what does an AP projection of the shoulder in a neutral position show?
greater tubercle partially superimposing the humeral head
posterior part of supraspinatus insertion demonstrated
what does an AP projection of the shoulder with internal rotation show?
lesser tubercle in profile
proximal humerus in true lateral position
insertion site of subscapular tendon demonstrated
RPO or LPO position
35-45 degrees toward affected side
Scapula parallel with the plane of the
IR
CR 2 in. medial and 2 in.
inferior to superolateral border
of the shoulder
Joint space between the
humeral head and the glenoid
cavity (scapulohumeral or
glenohumeral joint)
AP OBL Glenoid Cavity (Grasey Method)
Patient supine, arm abducted to 90 degrees with external rotation, vertical cassette, CR angle 15-30 degrees pointing into the arm pit
Inferosuperior Axial Projection (Lawrence method)
Place the patient in a chair at the end of the
exam table and have them extend the
shoulder over the table.
Shoulder should be over midpoint of IR
Tilt head away from IR
Humeral epicondyles should be vertical
Superioinferior Axial Projection (Lawrence Method)
What method shows these?
AC articulation
Joint relationship of proximal humerus and glenoid
cavity
Outer portion of coracoid process
Insertion points of subscapularis muscle (body of scapula) and teres minor muscle (inferior axillary border)
Superioinferior Axial Projection (Lawrence Method)
Patient supine, CR cephalic angle of 35 degrees
Demonstrates relationship of humeral head to the glenoid cavity
Useful in diagnosing posterior dislocation
AP Axial Trauma Shoulder
Useful in demonstrating
dislocations
Scapular Y PA OBL
Head beneath the coracoid
process (what dislocation?)
Anterior Subcoracoid
dislocation
Head projected beneath
acromion process (what dislocation?)
Posterior Subacromial
dislocation
Profiles the intertubercular groove free from superimposition of the surrounding shoulder structures
Patient supine
CR: 10-15 degrees posterior
Hand supinated
Intertubercular Groove Tangential Projection
SID: 72 in
Upright position
CR to midline at level of AC joints
With and without weights
Demonstrates dislocation, separation, and the function of joints
Acromioclavicular Articulations AP Projection: Bilateral
AC joint and clavicle projected above the acromion
CR 15 degrees cephalic
Acromioclavicular Articulations Alexander Method
Project clavicle off of scapula and ribs
Pt supine: CR 25-30 degrees
Pt upright leaning back: CR 15-25 degrees
Thinner patients require more angulation
AP Axial Projection Lordotic Position
Where is the CR for a Scapula AP projection?
CR perpendicualr to point 2 in below coracoid
Patient flexes elbow and places hand on posterior thorax
Delineates the acromion and coracoid process
Adjust body of scapula to be
perpendicular to the IR
Position of the arm
determines what portion of
the scapula will be
superimposed by the
humerus
Extending the arm
upward demonstrates
the body of the scapula
best
Scapula Lateral Projection
Examination of a joint after the injection of contrast material that outlines soft tissue and joint structures
Most commonly used to rule out bursitis
Shoulder Arthography
Immovable joint
Ex: skull sutures
synarthrodial
Slightly moveable joint
Ex: vertebrae
amphiarthrodial
Freely movable joint
Ex: hip, shoulder
diarthrodial
What is the advantage of a PA clavicle projection?
Closer to IR
Less exposure to gonads
How do you treat a fractured clavicle?
Sling for several weeks
what makes up the bony thorax?
sternum, 12 ribs, 12 thoracic vertebrae
Supports walls of pleural cavity & diaphragm
Volume of cavity able to change during respiration
Protects heart and lungs
functions of the bony thorax
flat bone, 6 inches in length, supports clavicles and provides attachment to 1st seven costal cartilages of ribs
sternum
which ribs are true ribs?
1-7, attached to sternum
which ribs are false ribs?
8-12, do not attach directly to the sternum; attach to costal cartilage of 7th rib
which ribs are floating ribs?
11-12, attached only to the vertebrae
articulate with C7 but rarely attach to sternum
cervical ribs
angle ______ from ribs 1-9 and then ______ from ribs 9-12
increases, decreases
production of red blood cells
erythropoiesis
where does erythropoiesis occur in the fetus?
mesodermal cells of yolk sac
where does erythropoiesis occur in 3-4 months to adolescence?
spleen, liver, and skeletal involvement
where does erythropoiesis occur in adulthood?
vertebrae, sternum, pelvis, ribs
what are the 8 joints that make up the bony thorax articulations?
Sternoclavicular
Costovertebral (1-12)
Costotransverse (1-10)
Costochondral (1-10)
Sternocostal (1-7)
Interchondral (6-10)
Manubriosternal
Xiphisternal
only points of articulation between the upper limbs and the trunk
gliding joints
sternoclavicular
rib head closely bound to the demifacets and 2 adjacent vertebral bodies
synovial gliding
costovertebral
tubercle of rib articulates with tranverse process of lower vertebrae
synovial gliding
costotransverse
articulation between costal cartilages and true ribs
no movement
cartilaginous synchondosis
sternocostal
articulation between rib costal cartilages and sternum
1st rib: cartilaginous
2-7: synovial gliding
costochondral
between 6-9 ribs: synovial gliding
between 9-10 ribs: fibrous syndesmosis
interchondral
cartilaginous synchondrosis
sternum
manubriosternal & xiphersternal
respiratory movement
Olique rib orientation
changes little
quiet respiration
respiratory movement
Degree of obliquity
decreases
Ribs carried
anteriorly, superiorly,
and laterally while
necks are rotated
inferiorly
deep inspiration
respiratory movement
Degree of obliquity
increases
Ribs carried inferiorly,
posteriorly, and
medially while the
necks are rotated
superiorly
deep expiration
degree of angulation for oblique projection of sternum depends on the ____ of the chest
depth
more or less angulation for a deep chest?
less
more or less angulation for a shallow chest?
more
Estimate body rotation by placing one hand on patient’s sternum and the other hand on the thoracic vertebrae to act as a guide
Top of IR 1.5 inches above jugular notch
Average body rotation is 15-20 degrees
PA Oblique Projection (RAO)
Sternum
Minimal rotation
Sternum projected free
from superimposition
of the spine
Sternum projected over
the heart
PA Oblique Projection (RAO, LPO) Sternum
Rotate patients hands posteriorly
Lock hands behind back
Film 24 x 30 cm lengthwise
IR 1.5 inches above jugular notch
Suspend deep inspiration
Lateral Projection (Upright)
Sternum
Bring hands above head
Film 24 x 30 cm lengthwise
IR 1.5 inches above jugular notch
Suspend deep inspiration
Lateral Projection (Supine)
Sternum
Sunken or “caved in” chest
Most common congenital chest wall abnormality in children
The problem is with the cartilage piece that connects each rib to the sternum. This costal cartilage connector is deformed, pushing the breastbone inward
pectus excavatum
IR @ T3 (just posterior
to jugular notch)
Arms rest by side of
patient with palms up
Turn head toward
affected side
Rotates spine slightly
away from side being
examined
Better visualization of
lateral manubrium
Suspend at end of
expiration
PA Projection Sternoclavicular Articulations
Rotate patient 10-
15 degrees
CR perpendicular
to SC Joint closest
to the IR (T2-T3)
LAO: Left side of interest
RAO: Right side of interest
PA Oblique Projection (RAO, LAO) SC Joints
Rib x-ray
localized point of interest: anterior ribs
PA projection
Rib x-ray
localized point of interest: posterior ribs
AP projection
Rib x-ray
localized point of interest: axillary portion of ribs
Oblique projection
how to image ribs above diaphragm
AP projection
1.5 in above shoulders
full inspiration
how to image ribs below diaphragm
lower edge of IR at iliac crest
full expiration
45 degree Oblique
Place affected side
closest to the IR
Center affected side
midway between
midsagittal plane and
lateral surface
Abduct arm of affected
side and elevate to
carry scapula away
from rib cage
Axillary Ribs AP Oblique Projection (RPO, LPO)
2 x distance between vertebral column and lateral border affected side
visualized
Axillary ribs free
of superimposition
Axillary Ribs AP Oblique Projection (RPO, LPO)
What are the 3 names the refer to the mid section of the sternum?
Corpus, body, gladiolus
The body is also called the
gladiolus
Xiphoid process is also called
ensiform
Sternal angle between ____ and _______
body, manubrium
what is between the ribs and sternum
costocartilage
which rib is the longest?
7th
Which rib articulates with the sternal angle?
2nd rib
What’s the space between the ribs called?
intercostal space
Width of the ribs gradually ________ from 1-12
decreases
Angle ______ from ribs 1-9 and then _______ 9-12
increases, decreases
which rib is shortest and widest?
1st
which ribs is shortest and skinniest?
12th
what is the purpose of erythropoiesis?
delivering oxygen to the body
What is the only point of articulation between upper limbs and trunk?
SC joints
Why must you do an oblique projection of the sternum verses?
Rotate so that the sternum is over the heart to provide a better background to see sternum
What position and breathing is best to see sternum?
RAO with shallow breathing
Bony landmark that can be used to utilize injury is above or below your diaphragm?
xiphoid process
what should your technique be for a rib x-ray compared to a chest x-ray?
80 kVp, increases mAs
PA oblique of ribs looking at:
side away
AP oblique of ribs looking at:
side closest
