11-2-11 Wednesday

Anatomy

Quiz questions involved:
-3 bones of shoulder: scapula, clavical, humerus
-anatomical name of shoulder jt: glenohumeral jt
-jt the trap acts on: scapulothoracic jt
-trap fiber rotate head and neck to the opposite side: upper fibers
-origin of deltoid: clavicle, acromion, spine of scapula


Rotator Cuff mm (SITS)

Suprapinatus
O: supraspinous fossa of scapula
I: greater tubercle of humerus
A: abducts glenohumeral
stabilize head of humerus in glenoid cavity

Infraspinatus
O: Infraspinous fossa of scapula
I: greater tubercle of humerus
A: laterally rotate g/h
adduct g/h
stabilize head of humerus in glenoid cavity

Teres Minor
O: upper 2/3 of lateral boarder of scapula
I: Greater tubercle of humerus
A: Laterally rotate g/h
Adduct g/h
stabilize head of humerus in glenoid cavity

Subscapularis
O: subscapular fossa of scapula
I: lesser tubercle of humerus
A: medially rotate g/h
stabilize head of humerus in glenoid cavity


Rhomboids (usually referred to singularly, not major and minor, because it is hard to differentiate)

Rhomboid Major
O: SP of T2-T5
I: Medial boarder of scapula b/w spine of scapula and inferior angle
A: adduct scapula (scapulothoracic jt)
elevate scapulothoracic jt
downwardly rotate scapulothoracic jt

Rhomboid minor
O: SP of C7-T1
I: upper portion of medial boarder of scapula across from spine of scapula
A: adduct scapulothoracic jt
elevate s/t
downwardly rotate s/t


Levator Scapula
O: TP C1-C4
I: medial boarder of scapula b/w superior angle and superior portion of spine of scap.
A: unilaterally
-elevate s/t
-downwardly rotate s/t
-laterally flex head and neck
-rotate head and neck to same side
Bilaterally
-extend head and neck

KNOW P. 242

Serratus Anterior
O: external surfaces of upper 8-9 ribs
I: anterior surface of medial boarder of scapula
A: origin fixed
-abducts s/t
-upwardly rotates s/t
-depress the s/t
-hold medial boarder of scap. against rib cage
scapula fixed
-may elevate thorax during forced inhalation

Sternalis - 5% of population has it

Pectoralis major (3 segments: clavicular, sternal, and costal fibers)
O: Medial 1/2 of clavicle, sternum, and cartilage of 1-6 ribs
I: greater tubercle of humerus
A: All fibers
-adduct g/h
-medially rotate g/h
-assist elevate thorax during forced inhalation (w/ arm fixed)
upper fibers (clavicular)
-flex g/h
-horizontally adduct g/h
lower fibers (costal)
-extend g/h

Pectoralis minor (deep to major and fibers are perpendicular too)
O: 3-5th ribs
I: medial surface of coracoid process
A: depress scapulothoracic jt
abduct s/t
downwardly rotate s/t
w/ scapula fixed- assist elevate thorax during forced inhalation

Subclavius
O: 1st rib and cartilage
I: inferior surface of middle 1/3 clavicle
A: depress clavicle and draw it anteriorly
elevate 1st rib (assist inhale)
stabilize sternoclavicular jt

Biceps Brachii
O: short head- coracoid process
long head- supraglenoid tubercle
I: tuberosity of radius and aponeurosis of biceps brachii
A: flex elbow (humeroulnar jt)
supinate forearm (radioulnar jt)
flex glenohumeral jt

Triceps brachii (only mm on posterior arm)
O: long head- infraglenoid process
lateral head- posterior surface of proximal half of humerus
medial head- posterior surface of distal half of humerus
I: olecranon process of ulna
A: all heads- extend the humeroulnar jt
long head- extend g/h jt
- adduct the g/h jt

Coracobrachialis (armpit mm)
O: coracoid process
I: medial surface of mid-humeral shaft
A: flex glenohumeral jt
adduct g/h



Axilla (armpit)
-4 walls:
lateral wall= biceps brachii and coracobrachialis
posterior wall= subscapularis and latissimaus dorsi
anterior wall= pectoralis major
medial wall= rib cage and serratus anterior

-brachial artery
plexus of nerves, veins, arteries, lymphs