the shoulder complex Flashcards
the humerus
spherical, shallow contricted neck, it faces upward, inward, backwards articulating with the scapulas glenoid fossa
sternoclavicular joint
articulation between the clavicle and the sternum
it functions to shock absorb against medial forces and helps prevent any displacement upward
clavicle can move up, down, forward, backward and rotate
acromioclavicular joint
irregular joint between acromion process of scapula and the lateral clavicle a thin, fibrous, capsule surrounds the joint
glenohumeral joint
the synovical ball and socket joint of the shoulder made stronger and deeper by the labrum as well as surrounding deltoid and rotator cuff
scapulothoracic joint
not a true joint
the area that provides movement of the scapula over the back side of the ribcage
allows for scapular elecvation, depression, protraction, retraction, abduction and adduction
sternoclavicular joint ligaments
anterior sternoclavicular ligament: which prevents upward displacement
posterior: prevents upward displacement
interclavicular: prevents lateral displacement
costoclavicular: prevents lateral and upward displacement
AC joint ligaments
acromioclavicular
coracoclavicular
conoid
trapezoid
*all try to keep AC joint together- most importantly keeping the joint from going superior
pec major
O: medial clavicle, sternum, costal cartilage of upper 6 ribs and aponeurosis of external oblique
I: greater tubercle of the humerus
A: flexes, adbucts and internally rotates shoulder
N: median and lateral pectoral
latissimus dorsi
O: SP of lower 6 thoracic and the lumbar vertebrae and posterior iliac crest and thoracolumbar fascia
I: medial margin of interbercular groove of humerus
A: extend, adduct and internal rotation
N: thoracodorsal
deltoid
O: lateral third clavicle, aromion process and spine of scapula
I: deltoid tuberosity of humerus
A: abducts the shoulder, anterior: flexion and internal rotation, posterior: extension, and external rotation
N: axillary
supraspinatus
O: supraspinatus fossa of scapula
I: greater tubercle of humerus
A: abducts and slight external rotation
N: suprascapular
infraspinatus
O: infraspinatus fossa of scapula
I: greater tubercle of humerus
A: external rotation and slight adduction
N: suprascapular
subscapularis
O: subscapular fossa of scapula
I: lesser tubercle of humerus
A: internal rotation
N: suprascapular
teres major
O: dorsal surface of inferior angle of scapula
I: lesser tubercle of the humerus
A: adduction, extension and internal rotation
N: subscapular
teres minor
O: axillary border of scapula
I: greater tubercle of humerus
A: external rotation
N: axilary
coracobrachialis
O: coracoid process of scapula
I: middle of humerus, medial surface
A: adduction, flexion of GH
N: musculocutaneous (c5-7)
trapezius
O: occipital bone, ligamentum nuchae, SP of the c7 and all tspine
I: lateral third of clavicle, acromion process and spine of scapula
A: upper: elevation; lower: depression, rotate, adducts and stabilizes the scapula; middle retraction and downward rotation
N: spinal accessory nerve CN11
rhomboid major
O: sp of 7 cervical and first thoracic vertebrae
I: vertebral border of scapula below the spine
A: rotates and retracts scapula, stabilizes and adducts
N: dorsal scapular
rhomboid minor
O: sp of 2-5 thoracic vertebrae
I: vertebral border of the scapula at the base of the spine of the scapula
A: adducts, stabilizes, rotates scapular, lowering its lateral angle
N: dorsal scapular
nerve supply to the shoulder
brachial plexus
branches to axillary, musculocutaneous, subscap, supra, dorsal scap, pectoral, and radial
blood supply to shoulder
subclavian and axillary arteries
brachial artery
levator scapulae
O: tp of c1-c4
I: vertebral border of scapula, above the spine of the scapula
A: elevates and adducts scapular, side bends neck when scap is fixed
N: dorsal scapular
pectoralis minor
O: anterior surface of rib 3-5
I: coracoid process of scapula
A: draws scapular anteriorly and downward rotation
N: medial pectoral
- would cause tilt to scapula if in dysfunction*
- not to be confused with serratus anterior which would cause winging*
serratus anterior
O: outer surface of ribs 1-9
I: entire length of vertebral border of scapula
A: protracts, and rotates scapula, stabilizes
N: long thoracic nerve