Test 2 Muscles of Shoulder and Arm Flashcards
deltopectoral grove
- between pectoralis major and deltoid
- cephalic vein runs through
anterior axioappendicular muscles
(thoracoappendicular or pectoral)
-move pectoral girdle
- pectoralis major
- pectoralis minor
- sublavius
- serratus anterior
clavipectoral triangle (deltopectoral)
formed by deltoid and pectoralis major diverging ,superiorly, along with the clavicle
pectoralis major origin
clavicular head-anterior surface of medial 1/2 of clavicle
sternocostal head-anterior surface of sternum, superior six costal cartalidges, apeneurosis of external oblique muscle
pectoralis major insertion
lateral lip of intertubercular sulcus(grove) of humerus
Pectoralis major innervation
Lateral and medial pectoral nerve clavicular head (C5, C6), sternocostal head ( C7, C8,T1)
pectoralis major action
- adducts and medially rotates humerus
- draws scapula anteriorly and inferiorly
-acting alone clavicular head flexes humerus and sternocostal head extends it from the flexed position
pectoralis minor insertion
Medial border and superior surface of coracoid process of scapula
pectoralis minor origin
3rd-5th costal ribs near their costal cartilages
pectoralis minor inervation
medial pectoral nerve (C8, T1)
pectoralis minor action
stabalizes scapula by drawing inferiorly nd anteriorly against thoracic walll
subclavius origin
junction of first rib and its costal cartilage
subclavius insertion
inferior surface of middle 1/3 of clavicle
subclavius innervation
subclavian nerve
C5, C6
subclavius action
anchors and depresses clavicle
serratus anterior origin
externl surface of lateral parts of 1st - 8th ribs
serratus anterior insertion
anterior surface of medial border of scapula
serratus anterior innervation
long thoracic nerve
C5, C6, C7
serratus anterior action
protracts scapula and holds against thoracic wall; rotates scapula
superficial posterior axioappendicular
extrinsic shoulder
trapezius
latissimus dorsi
deep posterior axioappendicular
extrinsic shoulder
levator scapula
rhomboids
scapulohumoral (intrinsic shoulder)
- deltoid
- teres major
- 4 rotator cuff muscles; supraspinatus, infraspinatus, teres minor, subscapularis
deltoid proximal attachment ,origin
- lateral 1/3 of clavicle
- acromion and spine of scapula
deltoid distal attachment, insertion
deltoid tuberosity of humerus
deltoid innervation
axillary neve
C5,C6
deltoid action
- clavicular (anterior) flexes and medialy rotates
- acromial (middle) abducts arm
- spinal (posterior) part extends and laterally rotates arm
supraspinatus proximal attachment , origin
supraspinous fossa of scapula
supraspinatous distal attachment , insertion
superior facet of greater tubercle of humerus
supraspinatus innervation
suprascapular nerve
C4, C5, C6
supraspinatus action
- initiates and assists deltoid in abduction of arm
- acts with rotator cuff muscles
infraspinatus proximal attachment, origin
infraspinous fossa of scapula
infraspinatus distal attatchment, insertion
middle facet of greater tubercle of humerus
infraspinatus innervation
suprascapular nerve
C5, C6
infraspinatus action
- laterally rotate arm
- help hold humoral head in glenoid cavity of scapula
teres minor proximal attachment, origin
Middle part of lateral border of scapula
Teres minor Distal attachment, insertion
Inferior facet of greater tubercle of humerus
Teres minor innervation
axillary nerve
C5,C6
teres minor action
- laterally rotate arm
- help hold humoral head in glenoid cavity of scapula
teres major proximal attachment , origin
Posterior surface of interior angle of scapula
Teres major distal attachment insertion
Medial lip intertubercular groove of humerus
teres major innervation
lower subscapular nerve
C5, C6
subscapularis proximal attachment , origin
subscapular fossa (most of anterior surface of scapula)
subscapularis distal attachment, insertion
Lesser tubercle of humerus
subscapularis innervation
Upper and lower subscapular nerves
C5 C6 C7
subscapularis action
- medially rotates and adducts arm
- helps hold humeral head in glenoid cavity
biceps brachii proximal attatchment, origin
short head:tip of corocoid process of scapula
long head: supraglenoid tubercle of scapula
biceps brachii distal attachment, insertion
- tuberosity of radius
- fascia of forearm via bicipital aponeurous
biceps brachii innervation
musculocutaneous nerve
C5 C6
biceps brachii action
- Supinates forearm and, when it is supinated, flexes forearm
- flexes arm
- short head helps resist dislocation of shoulder
brachialis proximal attachment ,origin
distal half of anterior surface of humerus
brachialis distal attachment , insertion
coronoid process and tuberosity of ulna
brachialis innervation
musculocutaneous nerve
C5 C6
brachialis action
flexes forearm in all positions
coracobrachialis proximal attachment, origin
tip of coracoid process of scapula
coracobrachialis distal attachment , insertion
middle 1/3 of medial surface of humerus
coracobrachialis innervation
musculocutaneous nerve
C6 C7 C8
coracobrachialis action
- helps flex and adduct arm
- resists dislocation of shoulder
triceps brachii proximal attachment origin
long head: infraglenoid tubercle of scapula
lateral head:posterior surface of humerus, superior to radial groove
medial head:posterior of surface of humerus, inferior to radial groove
triceps brachi distal attachment , insertion
proximal end of olecranon of ulna and fascia of forearm
triceps brachii innervation
radial nerve
C6 C7 C8
anconeus proximal attachment origin
lateral epicondyle of humerus
anconeus distal attachment insertion
lateral surface of olecrnon and superior part of posterior surface of ulna
anconeus innervation
radial nerve
C7 C8 T1
anconeus action
- Assist triceps in extending forearm
- stabilizes elbow joint
- abducts ulna during pronation
Posterior axioappendicular muscles
- Trapezius and Latissimus Dorsi(superifical)
- Levator scapula and rhomboid major and minor (Deep)
Trapezius origin
Middle superior nuchal line, EOP, nuchal ligament, C7-T12 spinous processes
Trapezius insertion
Lateral 1/3 of clavicle, acromion, spine of scapula
Trapezius Innervation
Spinal Accessory Nerve CN 11(C3, C4)
Trapezius Action
Descending fibers: elevate scapula
Ascending fibers:depress scapula
Middle fibers: retract scapula
Ascending and descending fibers: rotate glenoid cavity superiorly
Latissimus Dorsi Origin
Illiac crest, thoracolumbar fascia, inferior 3-4 ribs, inferior 6 spinous processes of verterbrae
Latissimus Dorsi Insertion
Floor of intertubercular sulcus of humerus
Latissimus Dorsi Innervation
Thoracodorsal Nerve
C 6,7,8 keeps the lats great!
Latissimus Dorsi Action
medially rotate, adduct and extend humerus
also helps bring body close to arms in upward climbing
Levator Scapula Origin
Posterior tubercles of transverse process of C1-C4
Levator Scapula Insertion
medial border of scapula superior to the spine of scapula
Levator Scapula Innervation
Dorsalscapular nerve
C3, C4, C5
Levator Scapula Action
Inferiorly tilt glenoid cavity by rotating scapula
elevates scapula
Rhomboid Minor Origin
Nuchal ligament
Spinous process of C7-T1
Rhomboid minor insertion
Triangular area of medial end of scapular spine
Rhomboid minor Innervation
Dorsalscapular nerve
C4, C5
Rhomboid Minor Action
Retract scapula
Fix scapula to thoracic wall
Rotate scapula to depress glenoid cavity
Rhomboid Major Origin
Spinous process of T2-T5
Rhomboid Major Insertion
medial border of scapula from level of spine to inferior angle
Rhomboid major innervation
Dorsalscapular nerve
C4, C5
Rhomboid major action
Retract scapula
Fix scapula to thoracic wall
Rotate scapula to depress the glenoid cavity
Muscles of the rotator cuff
SITS
Supraspinatus, Infrspinatus, Teres Minor, Subscapularis
