50 Muscle Atlas (Origin, Insertion, Action) Flashcards
Orbicularis Oris
Origin: muscle fibers surrounding opening of mouth
Insertion: skin at corner of mouth
Action: close lips, compress lips against teeth, protrude lips, shape lips during speech
Orbicularis Oculi
Origin: medial orbital wall
Insertion: circular path around orbit
Action: close eyes
Masseter
i) origin: maxilla and zygomatic arch
ii) insertion: angle and ramus of mandible
iii) action: elevates mandible as in closing mouth, assists in side-to-side movement of mandible, and protracts (protrudes) mandible
Temporalis
i) origin: parietal bone
ii) insertion: coronoid process and ramus of mandible
iii) action: elevates and retracts mandible and assists in side-to-side movement of mandible
Sternocleidomastoid
i) origin: sternum and clavicle
ii) insertion: mastoid process of temporal bone
iii) action: contraction of both muscles flexes the cervical part of the vertebral column and draws the head forward; contraction of one muscle rotates face toward side opposite of the contracting muscle
Rectus Abdominus
i) origin: pubic crest and pubic symphysis
ii) insertion: cartilage of fifth to seventh ribs and xiphoid process
iii) action: flexes vertebral column and compresses abdomen to aid in defecation, urination, forced expiration, and childbirth
Obliquus Externus Abdominis (External Oblique)
i) origin: inferior eight ribs
ii) insertion: iliac crest and linea alba
iii) action: contraction of both compresses abdomen and flexes vertebral column; contraction of one side alone bends vertebral column laterally; rotates vertebral column
internal oblique
i) origin: iliac crest, inguinal ligament, and thoracolumbar fascia
ii) insertion: cartilage of ribs 7-10 and linea alba
iii) action: compresses abdomen
transverse abdominis
i) origin: iliac crest, inguinal ligament, lumbar fascia, and cartilages of ribs 5-10
ii) insertion: xiphoid process, linea alba, and pubis
iii) action: compresses abdomen
diaphragm
i) origin: xiphoid process of sternum, costal cartilages and adjacent portions of ribs 7-12, lumbar vertebrae and their intervertebral discs
ii) insertion: central tendon
iii) action: contraction [inspiration] elevates ribs and increases anteroposterior and lateral dimension of thoracic cavity (relaxation [expiration] does the opposite)
trapezius
i) origin: occipital bone, ligamentum nuchae, and spines of seventh cervical and all thoracic vertebrae
ii) insertion: clavicle and acromion and spine of scapula
iii) action: elevates clavicle, adducts scapula, rotates scapula superiorly, elevates or depresses scapula, and extends head
serratus anterior
i) origin: ribs 1-8 or 1-9
ii) insertion: vertebral border and inferior angle of scapula
iii) action: abducts scapula and rotates it upwards
pectoralis major
i) origin: clavicle, sternum, and cartilages of second to sixth ribs
ii) insertion: greater tubercle and intertubercular sulcus of humerus
iii) action: flexes, adducts, and rotates arm medially
Subscapularis
i) origin: subscapular fossa of scapula
ii) insertion: lesser tubercle of humerus
iii) action: medially rotates arm at shoulder joint
Teres Major
i) origin: inferior angle of scapula
ii) insertion: lesser tubercle of humerus
iii) action: extends arm at shoulder joint, and assists in adduction and medial rotation of arm at shoulder joint
Teres Minor
i) origin: inferior lateral border of scapula
ii) insertion: greater tubercle of humerus
iii) action: laterally rotates and extends arm at shoulder joint
Deltoid
i) origin: acromial extremity of clavicle and acromion and spine of scapula
ii) insertion: deltoid tuberosity of humerus
iii) action: abducts, flexes, extends, and may alternately medially or laterally rotate arm
Infraspinatus
Origin: infraspinous fossa of scapula
Insertion: greater tubercle of humerus (posterior)
Actions: extends arm; adducts and laterally rotates humerus
Latissimus dorsi
i) origin: spines of inferior six thoracic vertebrae, lumbar vertebrae, crest of sacrum and ilium, inferior four ribs
ii) insertion: intertubercular sulcus of humerus (to anteromedial to humerus)
iii) action: extends, adducts, and rotates arm medially; draws arm inferiorly and posteriorly
Biceps brachii
Flexor
Origins: 2 - long head from tubercle superior to glenoid cavity
short head from coracoid process of scapula
Insertion: radial tuberosity
Action: flexes and supinates forearm; flexes arm
Brachioradialis
FLEXOR
i) origin: lateral border of distal end of humerus
ii) insertion: superior to styloid process of radius
iii) action: flexes forearm
Brachialis
FLEXOR
Origin: distal, anterior surface of humerus
Insertion: ulnar tuberosity and coronoid process of ulna
Action: flexes forearm
Triceps brachii
EXTENSOR
i) origins: 3
a) long head from a projection inferior to glenoid cavity of scapula
b) lateral head from lateral and posterior surface of humerus superior to radial groove
c) medial head from entire posterior surface of humerus inferior to a groove for the radial nerve
ii) insertion: olecranon of ulna
iii) action: extends forearm; extends arm
Flexor carpi radialis
i) origin: medial epicondyle of humerus
ii) insertion: second and third metacarpals
iii) action: flexes and abducts wrist
Flexor carpi ulnaris
i) origin: medial epicondyle of humerus and superior posterior border of ulna
ii) insertion: pisiform, hamate, and fifth metacarpal
iii) action: flexes and adducts wrist
Flexor digitorum superficialis
i) origin: medial epicondyle of humerus, coronoid process of ulna, and a ridge along lateral margin of anterior surface of radius
ii) insertion: middle phalanges
iii) action: flexes middle phalanges of each finger
Extensor carpi radialis longus
i) origin: lateral epicondyle of humerus
ii) insertion: second metacarpal
iii) action: extends and abducts wrist
Extensor digitorum
i) origin: lateral epicondyle of humerus
ii) insertion: second through fifth distal and middle phalanges
iii) action: extend phalanges
Extensor carpi ulnaris
i) origin: lateral epicondyle of humerus and posterior border of ulna
ii) insertion: fifth metacarpal
iii) action: extends and adducts wrist
Erector spinae (collective group)
Longissimus Thoracis
Longissimus Cervicis
Longissimus Capitis
Longissimus Capitis (erector spinae group)
Origin: Transverse processes of upper five thoracic vertebrae (T1-T5), articular processes of lower three cervical vertebrae (C5-C7)
Insertion: Posterior part of mastoid process of temporal bone
Action: Extends and rotates head
Longissimus Cervicis (erector spinae group)
Origin: Transverse processes of upper four or five thoracic vertebrae (T1-T5)
Insertion: Transverse processes of second through sixth cervical vertebrae
Action: Extends vertebral column, and lateral flexion
Longissimus Thoracis (erector spinae group)
Origin: Medial and lateral sacral crests, spinous processes and supraspinal ligament of lumbar and eleventh and twelfth thoracic vertebrae, and medial part of iliac crests
Insertion: Transverse processes of all thoracic vertebrae, between tubercles and angles of lower nine or ten ribs
Action: Extends vertebral column, also lateral flexion, and rotates ribs for forceful inspiration
Biceps femoris
i) origins: 2
a) long head arises from ischial tuberosity
b) short head arises from linea aspera of femur
ii) insertion: head of fibula and lateral condyle of tibia
iii) action: flexes leg and extends thigh
Semitendinosus
i) origin: ischial tuberosity
ii) insertion: proximal part of medial surface of shaft of tibia
iii) action: flexes lower leg and extends thigh
Semimembranosus
i) origin: ischial tuberosity
ii) insertion: medial condyle of tibia
iii) action: flexes lower leg and extends thigh
Gluteus medius
i) origin: ilium
ii) insertion: greater trochanter of femur
iii) action: abducts and rotates thigh medially
Iliacus
i) origin: iliac fossa and sacrum
ii) insertion: psoas major into lesser trochanter of femur
iii) action: psoas major and iliacus muscles acting together flex thigh at hip joint, rotate thigh laterally, and flex trunk on hip
Psoas major
i) origin: transverse processes and bodies of lumbar vertebrae
ii) insertion: with iliacus into lesser trochanter of femur
iii) action: psoas major and iliacus muscles acting together flex thigh at hip joint, rotate thigh laterally, and flex trunk on hip
Piriformis
i) origin: anterior sacrum
ii) insertion: superior border of greater trochanter of femur
iii) action: laterally rotates and abducts the thigh at the hip joint
Erector Spinae (summarized)
Origin: Several origins including iliac crest, ribs, vertebrae
Insertion: Several insertions including skull bones, vertebrae, ribs
Action: chief extensor of vertebral column. Unilaterally: lateral flexion of vertebral column.
Adductor longus
i) origin: pubic crest and pubic symphysis (anterior body of pubis)
ii) insertion: linea aspera of femur (mid-posterior)
iii) action: adducts, laterally rotates, and flexes thigh
Tensor fasciae latae
i) origin: iliac crest
ii) insertion: tibia by way of the iliotibial tract
iii) action: flexes and abducts thigh
Adductor magnus
i) origin: inferior ramus of pubis, and ramus and lower part of tuberosity of ischium
ii) insertion: linea aspera (anterior), adductor tubercle of femur
iii) action: adducts thigh, assists in medial rotation
Adductor magnus
i) origin: inferior ramus of pubis, and ramus and lower part of tuberosity of ischium
ii) insertion: linea aspera (anterior), adductor tubercle of femur
iii) action: adducts thigh, assists in medial rotation
Gluteus maximus
i) origin: iliac crest, sacrum, coccyx, and aponeurosis of sacrospinalis
ii) insertion: iliotibial tract of fascia lata and lateral part of linea aspera inferior to grater trochanter of femur
iii) action: extends and rotates thigh laterally
Gracilis
i) origin: pubic symphysis and pubic arch
ii) insertion: medial surface of body of tibia
iii) action: adducts thigh and flexes leg
Rectus femoris (one of quadriceps femoris)
i) origin: anterior inferior iliac spine
ii) insertion: patella and tibial tuberosity
iii) action: flexes thigh and extends leg
Vastus medialis
i) origin: linea aspera of femur
ii) insertion: patella and tibial tuberosity
iii) action: extends leg at knee
Vastus Lateralis
i) origin: greater trochanter and linea aspera of femur
ii) insertion: patella via quadriceps tendon and then tibial tuberosity via patellar ligament
iii) action: extends leg at knee joint
Gastrocnemius
i) origin: lateral and medial condyles of femur and posterior capsule of knee
ii) insertion: calcaneus by way of calcaneal (Achilles) tendon
iii) action: plantar flexes foot and flexes leg
Tibialis anterior
i) origin: lateral condyle and body of tibia and interosseous membrane
ii) insertion: first metatarsal and first (medial) cuneiform
iii) action: dorsiflexes and inverts foot
Flexor digitorum longus
i) origin: middle third of posterior surface of tibia
ii) insertion: distal phalanges of toes II – V.
iii) action: plantarflexion at ankle, flexes phalanges.
Peroneus (fibularis) longus
i) origin: head and body of fibula and lateral condyle of tibia
ii) insertion: first metatarsal and first cuneiform
iii) action: plantar flexes and everts foot
Extensor Digitorum Longus
i) origin: head and body of fibula and lateral condyle of tibia
ii) insertion: first metatarsal and first cuneiform
iii) action: plantar flexes and everts foot
