Muscles Flashcards
Pec Major INSERTION
Lateral lip of bicciptal groove
Pec Major Innervation
lateral and medial pectoral nerves
Pec Major Action
Adduction and medial rotation of humerus, Clavicular head = flexes humerus, Sternocostl head = extends humerus from flexed posiiton
Pec Minor ORIGIN
ribs 3,4,5
Pec Minor INSERTION
Coracoid process of scapula
Pec Minor Innervation
Medial pectoral nerve
Pec Minor Action
Stablises the scapula and acts as an accessroy muscle of respiration when pectoral girdle is fixed
Serratus Ant. ORIGIN
External surfaces of ribs 1-8
Serratus Ant. INSERTION
Ant. surface of medial scapular border
Serratus Ant. Innervation
long thoracic n
Serratus ant. Action
Protracts the scapula and holds it to the thoracic wall when punching or reaching object anteriorly
Rotates the scapula
Trapezius ORIGIN
Superior nuchal line, nuchal ligament spinous processes of C7-T12 vertebrae
Trapezius INSERTION
Lateral 1/3 of the clavicle, acromion and spine of the scapula
Trapezius innervation
- Spinal root of accessory nerve (CNXI)-motor fibres
Cervical nerves C3 and C4
Trapezius action (superior, middle and inferior fibres)
- Elevates the scapula (superior fibres)
- Retracts the scapula (middle fibres)
Depresses the scapula (inferior fibres)
Latissimus Dorsi ORIGIN
Spinous processes of the T7-T12 vertebra, thoracolumbar fascia, iliac crest, lower 4 ribs
Latissimus Dorsi INSERTION
Floor of the intertubercular groove/bicipital groove of the the humerus (mnemoic - lady btw 2 majors)
Latissimus dorsi innervation
thoracocdorsal n
Lat Dorsi Action
Extension, adduciton and medial rotation of humerus.
Levator Scapulae Origin
Transverse processes of C1-4
Levator Scapulae Insertion
Superior medial border of scapula
Levator scapulae innervation
dorsal scapular n
Rhomboids innervation
dorsal scapular n
Levator scapulae action
elevates scapula
Rhomboids action
retracts scapula and rotate scpaula
Deltoid ORIGIN
Lateral 1/3 of clavicle, acromion and spine of scapula
Deltoid INSERTION
deltoid tuberosity of humerus
deltoid innervation
axillary
Anterior fibres of deltoid Action
flexes arm (assisted by pec major)
Middle fibres of deltoid action
abdution of the arm after 15 degrees
posterior fibres of detloid action
extend arm
Teres major origin
inferior border of scapular
teres major insertion
intertubercular groove
teres major innervation
lower scapular nerve
teres major action
adduction and medial rotation of arm at shoulder j
supraspinatus origin
supraspinous fossa
supraspinatus insertion
greater tubercle of humerus
supraspinatus innervation
suprascapular n
infraspinatus origin
infraspinous fossa
infraspinatus insertion
greater tubercle of humerus
infraspinatus innervation
suprascapular n
supraspinatus action
abducts the arm first 15 degrees
infraspinatus action
lateral rotator of arm at shoulder j
teres minor origin
superior part of lateral scapular border
teres minor insertion
greater tubercle of humerus
teres minor innervation
axillary n
teres minor action
lateral rotator of arm at shoulder j
subscapularis origin
subscapular fossa
subscapularis insertion
lesser tubercle of humerus
subscapularis innervation
upper and lower subscapular n
subscapularis action
medial rotation
biceps brachii origin (long and short head)
long head = supraglenoid tubercle of scapula, short head = coracoid process of scapula
biceps brachiii insertion
radial tuberosity
biceps brachii innervation
musculocutaneous n
biceps brachii action
flexor at elbow, supinator of the forearm
coracobrachialis origin
coracoid process
coracobrachilais inerstion
midshaft of humerus
coracobrachililis innervation
musculocutaneous n
coracobrachialis action
weak flexor and adductor of the arm
brachialis origin
midshaft of humerus
brachialis insertion
ulnar tuberosity
brachialis innervation
musculocutaneous
brachialis action
chief flexor of the forearm
what is the chief flexor of the forearm
brachialis
triceps brachii origin (long, medial and lateral heads)
long head: infraglenoid tubercle
Medial head: posterior surface of humerus, inferior to the radial groove
Lateral head: posterior surface of the humerus, superior to radial groove
triceps brachii insertion
olecranon process
triceps innervation
radial n
triceps action
- Chief extensor of the forearm
Long head stabilises the head of humerus in arm when abducted
pronator teres origin
medial epicondyle of humerus
pronator teres insertion
midshaft of radius
pronator teres innervation
median
pronator teres action
pronator