OS 203 2 Shoulder and Arm - Sheet1 Flashcards
5 joints of pectoral girdle
vertebrocostal, costosternal, sternoclavicular, acromioclavicular, glenohumeral
2 articulations of pectoral girdle
subacromial, scapulothoracic
least movement among the joints of the girdle
vertebrocostal, costosternal, sternoclavicular, acromioclavicular, glenohumeral
sternoclavicular - mobility
greeeat
costosternal - mobility
little
what is the glenoid labrum
cartilage surrounding the rim of the glenoid fossa
glenoid labrum deepens the fossa by _ and increases depth by _
deepens by 2.5 mm, increases depth by 100%
reduces glenoid depth by 50%
anterior labral detachment
which among the anterior (superior, middle, inferior) ligaments is the strongest
middle
which among the anterior (superior, middle, inferior) ligaments is the weakest
inferior
rotator cuff synergism
supraspinatus-teres minor; subscapularis-antagonist-infraspinatus
supraspinatus vector
up
infraspinatus vector
down
subscapularis
down
glenohumeral abduction:scapulothoracic articulation
2 is to 1 (for every 2 deg glenohumeral abduction, 1 deg scapulothoracic articulation)
components of the intricate collateral system
circumflex scapular artery, circumflex humeral artery
supplies blood to the dorsum of scapula
circumflex scapular artery (also anastomoses around scapula)
encircles surgical neck of humerus, anastomosing w each other
circumflex humeral artery
anterior & posterior circumflex humeral artery: size, supplies blood to where
anterior - smaller; supplies to the shoulder… posterior - larger, glenohumeral jt and surrounding muscles
quadrangular space artery and innervation
posterior circumflex artery, axillary nerve
triangular interval - artery and innervation
profunda brachii, radial nerve
triangular space - artery and nerve
circumflex scapular artery (no nerve)
xray: humerus superimposed with glenoid fossa (4)
anterior labrum detachment, torn capsule, long head of biceps attenuated, subscapularis muscles destroyed
what happens when dislocation occurs
muscles will contract (sudden pain), 6-8 wks before healing
longest bone in the body (and 2nd longest)
femur, humerus
head articulates w
glenoid fossa
anatomical neck, what’s attached?
glenohumeral joint capsule
attachment of deltoid
deltoid tuberosity (lateral)
radial groove what passes here
radial nerve and deep artery
capitulum articulates with
head of radius
trochlea articulates with
head of ulna
humerus: fossae of anterior surface receives what? tapos sa posterior?
anterior: coronoid fossa (ulna coronoid process), radial fossa (radial head); posterior: olecranon fossa (olecranon process of ulna during extension)
joints of the elbow (3) what kind?
humeroulnar (trochleoulnar) - ginglymus, proximal radioulnar - trochoid/pivot, humeroradial (capituloradial) - condyloid (shallow ball and socket)
ligaments of the elbow (3)
medial/ulnar collateral ligament, lateral/radial collateral ligament, annular ligament
holds the long head of the biceps in the groove
transverse humeral ligament
main flexor of forearm
brachialis
enables you to put down something slowly (extends slowly during extension)
brachialis
resists downward dislocation of humeral head
coracobrachialis
flexes shoulder
coracobrachialis
main extensor of the triceps
medial
least active in the triceps, stabilizes glenohumeral joint by resisting inferior displacement of humeral head
long head
blood flow: heart –> ? –> a.a. –> ? –> r. sub? –> ? –> ? –> ?
heart -> aorta -> aortic arch -> brachiocephalic -> right subclavian -> axillary -> brachial -> radial/ulnar
allow alternative route for blood flow in case of injury
circumflex arteries
what can happen when the posterior circumflex artery and axillary nerve (located where?) are damaged?
located near the surgical nec; deterioration of deltoids when damaged!
circumflex scapular artery arises from? circumflex humeral arteries arise from? supplies?
from subscapular artery; from axillary artery, supplies deltoid
limb development happens in
weeks 5-8
connects the shoulder to the axial skeleton
clavicle
ligaments that stabilize the ligament (3)
interclavicular, sternoclavicular, costoclavicular
does the clavicle have a medullary cavity?
nope, spongy bone itu
1st bone to ossify
clavicle
increase the resilience of the clavicle
S shape! (convex medial, concave lateral)
joint that is last to ossify
sternoclavicular joint
found at both joints of the clavicle
fibrocartilage disc
what attaches to conoid tubercle of the clavicle
conoid and coracoclavicular ligaments
what attaches to trapezoid line of the clavicle
trapezoid ligament
attachment of subclavius muscle and costoclavicular ligament
subclavian groove of clavicle
attachment of biceps brachii sa scapula
supra- & infraglenoid tubercle
trapezius action(s)
descending - elevate scapula; middle - retract scapula; ascending - depress scapula
levator & rhomboids vs serratus
the first 2 retracts the scapula and depresses the glenoid cavity; serratus anterior protracts the scapula (*punching) and elevates glenoid cavity so arms can be raised above the shoulder
infraspinatus & teres minor vs subscapularis
subscapularis - medial rotator of arm
ends of pec major
clavicular and sternal
pec minor stabilizes the
scapula
subclavius stabilizes the
clavicle
absence of clavicle -> condition, defect
cleidocranial dysostosis / cleidocranial dysplasia, can touch shoulders together
1 shoulder blade sits higher on the back than the other
sprengel’s deformity / congenital high scapula
proximal fracture near surgical nerve injuries
axillary nerve & arteries -> deltoid deterioration (*eto yung circumflex na sabi kanina :|)
medial fracture injury
radial nerve (at radial groove) -> inability to move wrists up and down
distal fracture
brachial artery & median nerve -> impede wrist and phalangeal movement (and sensation)