Muscles That I Need to Know Flashcards
Frontal Belly of Epicranius
origin: epicranial aponeurosis; insertion: skin of eyebrow; action: raises eyebrows
Occipital Belly of Epicranius
origin: occipital and temporal bones; insertion: epicranial aponeurosis; fixes aponeurosis and pulls scalp posteriorly
Orbicularis Oculi
origin: frontal and maxilla bones; insertion: tissue of eyelid; action: closes eyelid (such as blinking, squinting and winking)
Corrugator Supercilli
origin: frontal bone; insertion: skin of eyebrow; action: draws eyebrows meidally ( as in frowning)
Zygomaticus Major and Minor
origin: zygomatic bone; insertion: skin and muscle at corner of mouth; action: elevates lateral corners of the mouth (as in smiling)
Risorius
origin: fascia of masseter muscle; insertion: skin at corner of the mouth; action: draws corners of lip laterally (tenses the lip), synergist of the zygomaticus muscles
Orbicularis Oris
origin: indirectly to maxilla and mandible; insertion: inserts into muscle and skin at corners of the mouth; action: closes lips, purses and protrudes lips (such as kissing and whistling)
Buccinator
origin: maxilla and mandible; insertion: orbicularis oris; action: compresses cheek as in whitlsting or sucking through a straw
Masseter
origin: zygomatic arch and zygomatic bone; insertion: mandible; action: primer mover of mandible elevation (as in clinching teeth)
Temporalis
origin: temporal bone; insertion: coronoid process of mandible; action: elevates and retracts mandible (synergist of masseter)
Platysma
origin: fascia of chest (over pectoral muscles and deltoid); insertion: lower margin of mandible and skin; action: tenses skin of neck (pulls lower lip back and downward as in shaving )
Sternocleidomastoid
origin: manubrium of sternum and medial calvical; insertion: mastoid process of temporal bone and occipital bone; action: simultaneous contraction of both , flexes the neck; acting independently rotates head toward shoulder on opposite side
Pectoralis Major
origin: clavical, sternum, cartilage of ribs 1-6 and aponeurosis of external oblique muscle; insertion: humerus; action: prime mover of arm flexion, adducts and medially rotates arms (also acts in forced inhalation)
Serratus Anterior
origin: lateral aspect of ribs 1-8; insertion: anterior surface of medial border of scapula; action: primer mover to abduct scapula (allows arm to be raised and deliver a punch as in boxing)
Deltoid
origin: lateral 1/3 of clavical, acromion and spine of scapula; insertion: deltoid tuberosity of humerus; action: prime mover of arm abduction
Pectoralis Minor
origin: ribs 3-5; insertion: coracoid process of scapula; action: with ribs fixed, draws scapula forward and inferior, with scapula fixed, elevates the rib cage as in forced inspiration
External Intercostals
origin: inferior border of rib above ; insertion: superior border of rib below; action: elevate rib cage, synergist of diaphragm
Diaphragm
origin: inferior border of rib and sternum, costal cartilages of last 6 ribs and lumbar vertebrae; insertion: central tendon; action: prime mover of inspiration(flattens the diaphragm which increases volume of thoracic cavity)
Rectus Abdominis
origin: pubic crest and symphysis; insertion: xiphoid process and costal cartilages of ribs 5-7; action: flexes the vertebral column (as in sit ups)
External Oblique
origin: lower 8 ribs; insertion: linea alba, pubic crest, iliac crest; action: main function is to rotate the trunk (used in oblique sit ups), synergist of rectus abdominis
Internal Oblique
origin: lumbar fascia and iliac crest; insertion: linea alba, pubic crest, and costal cartilages of ribs 10-12; action: same as external obliques
Transversus Abdominis
origin: iliac crest, cartilages of last 5-6 ribs and lumbar fascia; insertion: linea alba and pubic crest; action: compresses the abdomen
Trapezius
origin: occipital bone, spines of c7-T12, vertebra; insertion: acromion and spine of scapula, lateral clavicle; action: superior fibers elevate scapula (as in shrugging your shoulders); inferior fibers depress scapula; extends head
Latissimus Dorsi
origin: spinous processes of T7=T12 and L1-L5 vertebra, last 3 ribs and iliac crest; insertion: humerus; action: prime mover of arm extension (brings arm down in power stroke), adducts and medially rotates arm
Rhomboids Major and Minor
origin: spinous processes of c7 and t1-t5; insertion: medial border of scapula; action: stabilizes and adducts (retracts) scapula
Biceps Brachii
origin: short head- coracoid process, long head- glenoid cavity; insertion: radial tuberosity; action: flexion (powerful) and suppination of forearm antagonist of triceps brachii
Brachialis
origin: distal, anterior humerus; insertion: proximal ulna; action: flexes forearm (antagonist of triceps brachii)
Brachioradialis
origin: humerus; insertion: styloid process of radius; action: synergist of forearm flexion (antagonist of triceps brachii)
Triceps Brachii
origin: long head- glenoid cavity, lateral head- posterior humerus; insertion: olecranon of ulna; action: prime mover of forearm extension, extends arm at shoulder
Sartorius
origin: anterior superior iliac spine; insertion: medial surface of proximal tibia; action: flexes, abducts, and laterally rotates thigh at hip, flexes leg at the knee
Adductor Magnus
origin: ischial and pubic rami and ischial tuberosity; insertion: linea aspera and femur; action: adducts, medially rotates and flexes thigh at hig
Adductor Longus
origin: pubis; insertion: linea aspera; action: same as adductor magnus
Gracilis
origin: pubis; insertion: medial surface of tibia just inferior to the medial condyle; action: adducts thigh, flexes and medially rotates leg
Rectus Femoris
origin: anterior inferior iliac spine; insertion: patella and tibial tuberosity; action: extends leg and flexes thigh
Vastus Lateralis
origin: greater trochanter and linea aspera; insertion: patella and tibial tuberosity; action: extends leg
Vastus Medialis
origin: linea aspera; insertion: patella and tibial tuberosity; action: extends leg
Vastus Intermedius
origin: femur; insertion: patella and tibial tuberosity; action: extends leg
Tensor Fasciae Latae
origin: anterior iliac crest and iliac spine; insertion: iliotibial tract; action: laterally stabilizes hip and knee joints, assists in flexion, abduction and medial rotation of the thigh
Gluteus Maximus
origin: dorsal ilium, sacrum and coccyx; insertion: femur and iliotibial tract; action: primary extensor of thigh (when climbing stairs but not when walking), laterally rotates and abducts thigh
Gluteus Medius
origin: ilium; insertion: greater trochanter of femur; action: abducts and medially rotates thigh
Biceps Femoris
origin: long head- ischial tuberosity, short head- distal femur; insertion: head of fibula and lateral condyle of tibia; action: extends thigh and flexes leg
Semitendinosus
origin: ischial tuberosity; insertion: medial aspect of proximal tibia; action: extends thigh and flexes leg
Semimembranosus
origin: ischial tuberosity; insertion: medial condyle of tibia and lateral condyle of femur ; action: extends thigh and flexes leg
Tibialis Anterior
origin: lateral condyle and upper 2/3 of tibia, interosseous membrane; insertion: metatarsal 1; action: prime mover of dorsiflexion, inverts foot
Extensor Digitorum Longus
origin: tibia, fibula, and interosseous membrane; insertion: middle and distal phalanges of toes 2-4; action: prime mover of toe extension, dorsiflxes foot
Fibularis Longus
origin: head and upper portion of fibula; insertion: under foot to metatarsal 1; action: plantar flexes and everts foot
Gastrocnemius
origin: medial and lateral condyles of femur; insertion: calcaneus via calcaneal tendon; action: plantar flexes foot when leg is extended
Soleus
origin: proximal portion of tibia and fibula interosseious memebrane; insertion: calcaneus via calcaneal tendon; action: plantar flexes foot
