Action, Origin, Insertion Muscles Flashcards
Masseter
A: closes mouth
O: Maxilla
I: mandible
Temporalis
A: elevates and retracts mandible
O: temporal bone
I: mandible
Genioglossus
A: depresses tongue and protracts it
O: mandible
I: tongue
Stylohyoid
A: elevates hyoid and draws it posteriorly
O: styloid process
I: hyoid bone
Digastric
A: elevates hyoid, depresses mandible
O: mandible, mastoid process
I: hyoid bone
Sternocleidomastoid
A: bilaterally (flex neck), unilaterally (rotate head side to side, opposite contracting muscle
O: sternum, clavicle
I: mastoid process
Diaphragm
A: expand thoracic cavity
O: xiphoid process, ribs, lumbar vertebrae
I: central tendon
External Intercostals
A: elevates ribs for inhalation
O: inferior border of rib above
I: superior border of rib below
Internal intercostals
A: depresses ribs for forced exhalation
O: superior border of rib below
I: inferior border of rib above
Rectus abdominis
A: flexes trunk
O: pubic crest
I: xiphoid process
External oblique
A: compresses abdomen, flexion and lateral flexion of trunk
O: inferior eight ribs,
I: iliac crest
Internal oblique
A: compresses abdomen, flexion and lateral flexion of trunk
O: iliac crest
I: last three or four ribs
Transversus abdominis
A: compresses abdomen
O: iliac crest
I: xiphoid process
Pectoralis major
A: adducts and medially rotates arm at shoulder, clavicular head flexes arm, sternocostal head extends arm
O: clavicle, sternum, ribs
I: greater tubercle and intertubercular sulcus
Pectoralis minor
A: depresses and abducts scapula, elevates ribs during forced inhalation
O: ribs 3-5
I: coracoid process of scapula
Serratus anterior
A: abducts scapula, elevates ribs
O: superior 8 or 9 ribs
I: scapula
Trapezius
A: elevates, depresses, and adducts scapula, extends head
O: superior nuchal line, 7th cervical and all thoracic vertebrae
I: clavicle and scapula
Levator scapulae
A: elevates scapula
O: superior cervical vertebrae
I: scapula
Rhomboideus major
A: elevates and adducts scapula
O: 2nd to 5th thoracic vertebrae
I: vertebral border of scapula
Rhomboideus minor
A: elevates and adducts scapula
O: 7th cervical and first thoracic vertebrae
I: scapula
Latissimus dorsi
A: extends, adducts, and medially rotates humerus
O: iliac and sacral crests
I: intertubercular sulcus
Deltoid
A: abducts, flexes, and extends arm
O: scapula
I: deltoid tuberosity
Teres major
A: extends arm
O: inferior angle of scapula
I: intertubercular groove of humerus
Teres minor
A: extends and adducts arm
O: scapula
I: greater tubercle
Supraspinatus
A: abducts arm
O: supraspinatus fossa of scapula
I: greater tubercle of humerus
Infraspinatus
A: lateral rotation at shoulder
O: infraspinatus fossa of scapula
I: greater tubercle of humerus
Subscapularis
A: medial rotation at shoulder
O: subscapular fossa of scapula
I: lesser tubercle of humerus
Coracobrachialis
A: flexes and adducts arm at shoulder
O: coracoid process
I: humerus
Subclavius
A: depresses and protracts shoulder
O: first rib
I: clavicle
Biceps brachii
A: flexes forearm at elbow, supinates forearm
O: supraglenoid tubercle and coracoid process
I: radial tuberosity
Brachialis
A: strongest forearm flexor at elbow joint
O: humerus
I: ulnar tuberosity
Brachioradialis
A: flexes forearm at elbow
O: humerus
I: styloid process of radius
Triceps Brachii
A: extends forearm at elbow joint
O: infraglenoid tubercle of scapula, posterior surface of humerus (x2)
I: olecranon of ulna
Supinator
A: supinates forearm
O: lateral epicondyle of humerus
I: proximal 1/3 of radius
Pronator teres
A: pronates forearm
O: medial epicondyle of humerus and coronoid process of ulna
I: radius
Palmaris longus
A: weakly flexes wrist
O: medial epicondyle of humerus
I: palmar aponeurosis
Gluteus maximus
A: extends thigh at hip and laterally rotates thigh
O: iliac crest
I: iliotibial tract
Gluteus medius and minimus
A: abducts and medially rotates hip
O: ilium
I: greater trochanter
Tensor fasciae latae
A: flexes and abducts thigh at hip joint
O: iliac crest
I: iliotibial tract
Pectineus
A: flexes and adducts hip
O: pubic
I: lesser trochanter
Adductor brevis
A: adducts, flexes hip
O: pubis
I: linea aspera
Adductor longus
A: adducts and flexes hip
O: pubic crest
I: linea aspera
Adductor magnus
A: adducts, flexes hip
O: pubic and ischial tuberosity
I: linea aspera
Gracilis
A: adducts hip, flexes knee
O: pubic
I: medial proximal tibia
Rectus femoris
A: extends knee, flexes hip
O: iliac spine
I: tibial tuberosity
Vastus medialis
A: extends knee
O: linea aspera
I: tibial tuberosity
Vastus lateralis
A: extends knee
O: greater trochanter and linea aspera
I: tibial tuberosity
Vastus intermedius
A: extends knee
O: femur
I: tibial tuberosity
Sartorius
A: flexes knee, flexes abducts and laterally rotates hip
O: anterior superior iliac spine
I: tibia
Biceps femoris
A: flexes knee, extends hip
O: ischial tuberosity
I: tibia
Semitendinosus
A: flexes knee, extends hip
O: ischial tuberosity
I: tibia
Semimembranosus
A: flexes knee, extends hip
O: ischial tuberosity
I: medial condyle of tibia
Gastrocnemius
A: plantar flexes ankle, flexes knee and inverts foot
O: lateral and medial epicondyles of femur
I: calcaneus
Soleus
A: plantar flexes ankle
O: fibula and tibia
I: calcaneus
Peroneus longus
A: plantar flexes ankle, everts foot
O: upper 2/3 of fibula
I: first metatarsal and fist cuneiform
Tibialis anterior
A: dorsiflexes ankle, inverts foot
O: lateral condyle, tibia
I: first metatarsal and first cuneiform
Tibialis posterior
A: planter flexes ankle, inverts foot
O: posterior tibia and fibular
I: metatarsals, navicular, all three cuneiforms, cuboid
