lab five: myology - pectoral area and ventral upper limb Flashcards
parallel
fascicles are parallel to the longitudinal axis and terminate in flat tendons
ex: sternohyoid
fusiform
fascicles are nearly parallel to the longitudinal axis with a belly that narrows toward the tendons
ex: biceps brachii
circular
fascicles are arranged concentrically
ex: orbicularis oculi
triangular
fascicles converge from a broad origin to a narrow insertion
ex: trapezius
unipennate
fascicles attach to one of the two sides of a tendon
ex: extensor digitorum longus
bipennate
fascicles attach on both sides of a central tendon
ex: rectus femoris
multipennate
fascicles attach obliquely to tendons in various direction
ex: deltoid
muscles crossing shoulder joint
pectoralis major, latissimus dorsi, deltoid
action of pectoralis major
adducts, flexes and medially rotates arm
origin of pectoralis major
clavicle, sternum, and ribs
insertion of pectoralis major
humerus (intertubercular sulcus)
action of latissimus dorsi
adducts, extends and medially rotates arm
origin of latissimus dorsi
scapula, vertebral column, and iliac crest
insertion of latissimus dorsi
humerus (intertubercular sulcus)
action of deltoid
abducts, flexes, and rotates arm medially and laterally
origin of deltoid
clavicle and scapula
insertion of deltoid
deltoid tuberosity of humerus
posterior thorax muscles
trapezius and levator scapulae
action of trapezius
adducts and rotates scapula; elevation and depression of scapula
origin of trapezius
superior nuchal line of occipital bone and vertebral column
insertion of trapezius
lateral clavicle and scapular spine and acromion
action of levator scapulae
elevation of scapula, lateral neck flexion
origin of levator scapulae
transverse processes of cervical vertebrae (C1-C4)
insertion of levator scapulae
medial border (scapula)
anterior thorax muscle
pectoralis minor
action of pectoralis minor
stabilizes, abducts and rotates scapula
origin of pectoralis minor
ribs 3-5
insertion of pectoralis minor
scapula (coracoid process)
shoulder joint muscles (indicates rotator cuff muscles)
subscapularis, infraspinatus, supraspinatus, teres minor, teres major, coracobrachialis
action of subscapularis
medial rotation of arm, stabilizes humerus head in glenoid cavity
origin of subscapularis
subscapular fossa of scapula
insertion of subscapularis
lesser tubercle of humerus
action of infraspinatus
lateral rotation of arm, stabilizes humerus head in glenoid cavity
origin of infraspinatus
infraspinous fossa of scapula
insertion of infraspinatus
greater tubercle of humerus
action of supraspinatus
abduction of arm, stabilizes humerus head in glenoid cavity
origin of supraspinatus
supraspinous fossa of scapula
insertion of supraspinatus
greater tubercle of humerus
action of teres minor
lateral rotation and adduction of arm, stabilizes humerus head in glenoid cavity
origin of teres minor
lateral border of scapula
insertion of teres minor
greater tubercle of humerus
action of teres major
medial rotation, adductions and extension of arm