Muscles w AOIs exam 2 Flashcards
Trapezius
Origin: occipital bone
Insertion: clavicle, acromion process and spine of scapula
Action:
superior fibers- elevate and superiorly rotate scapula
middle fibers- retract scapula
inferior fibers- depress scapula
latissimus dorsi
Origin: spinous processes of t2-t12. ribs 8-12, thoracumbar fascia
Insertion:intertubular sulcus of humerus
Action: agonist of arm extension, adducts and medially rotates arm
Deltoid
Origin: acromial end of clavicle, acromion and spine of scapula
Insertion: deltoid tuberosity of humerus
Action:
anterior fibers- flex and medial rotate arm
middle fibers- agonist of arm abduction
posterior fibers- extend and laterally rotate arm
pectoralis major
Origin: medial clavicle, costal cartilage of ribs 2-6, body of sternum
Insertion: lateral part of intertubular sulcus of humerus
Action: agonist of arm flexion, adducts and medially rotates arm, horizontal adduction of arm
Biceps Brachii (long and short heads)
origin:
long head- supraglenoid tubercle of the scapula
short head- coracoid process of scapula
insertion
insertoin: radial tuberosity and bicipital aponeurosis
action: flexes forearm, powerful supinator of forearm
-long head flexes arm
psoas major (and what is this a part of)
PART OF ILIOPSOAS
Origin: transvers processes and bodies of vert t12-l5
insertion: lesser trochanter of femur with iliacus
action: flexes thigh
iliacus (and what is this a part of)
PART OF ILIOPSOAS
Origin: iliac fossa
Insertion: lesser trochanter of femur with psoas major
Action: flexes thigh
Gluteus maximus
Origin: sacrum, coccyx, iliac crest
Insertion: iliotibial tract of fascia lata, linea aspera and gluteal tuberosity of femur
Action: extends thigh, laterally rotates thigh
rectus femoris
Origin: anterior inferior iliac spine
Insertion: quadriceps tendon to patella and patella ligament to tibial tuberosity
action: flexes thigh, extends leg
tibialis anterior
origin: lateral condyle and proximal shaft of tibia, interosseous membrane
Insertion: metatarsal 1 and first medial cunciform
ACtion: dorsiflexion and inverts foot
gastrocnemius
Origin: superior and posterior surface of lateral and medial condyles of femur
Insertion: calcaneus
Action: flexes leg, plantar flexes foot
Frontal belly of occipitofrontalis
O: epicranial aponeurosis
I: skin ovr supraorbital margin
action: moves scalp, eyebrows, and forhead
orbicularis occuli
origin: medial wall or margin of orbit
insertion: skin surrounding eyelids
action: closes eye, blinking, squinting
depressor anguli oris
o: body of mandible
I: skin at inferior angle of mouth
action: produces frowning
zygomaticus major
O:Zygomatic. bone
insertion: skin at superolateral edge of mouth
Action: smile
masseter
Origin: zygomatic arch
Insertion: Ramus at angle of mandible
Action: elevates and protracts mandible, prime mover of jaw closure
sternocleidomastoid
origin: manubrium and sternal end of clavicle
insertion: mastoid process
action:
unilateral - lateral flexion, rotation of head side to side
bilateral - flexes neck
splenus capitis
Origin: ligamentum nuchae and spinous process of c7-t3
Insertion: occipital bone and mastoid process of temporal bone
actin:
unilateral- turns head to same side
bilateral- extends head/neck
external oblique
origin: external and inferior borders of the inferior 8 ribs
insertion: linea alba by a broad aponeurosis, some to iliac crest
action:
unilateral- lat flexion of vert. column. rot of vert column to opposite side
bilateral- flexes vert column and compress abdominal wall, used in forced exhalation
rectus abdominis
origin: superior surface of pubis near symphesis
insertion: xiphoid process of sternum, inferior surfaces of ribs 5-7
