Muscles (Origins, Insertions, & Actions) Flashcards
Orbicularis oculi muscle
Origin: orbit
Insertion: skin of eyelid
Action: Closes eyes, squints eyes
Orbicularis oris muscle
Origin: Maxilla and mandible
Insertion: Muscle and skin of lips
Action: Closes lips, purses lips
Temporalis muscle
Origin: Temporal fossa
Insertion: Mandible (coronoid process)
Action: Closes jaw, elevates and retracts mandible
Zygomaticus muscles (major and minor)
Origin: Zygomatic bone
Insertion: Corners of mouth
Action: raises corners of mouth (smiling muscle)
Epicranius muscle (aka occipitofrontalis)
Has two bellies (frontal and occipital)
Frontal belly origin: epicranial aponeurosis
Frontal belly insertion: skin of brow line
Frontal belly action: raises eyebrows
Occipital belly origin: occipital and temporal bones
Occipital belly insertion: epicranial aponeurosis
Occipital belly action: fixes aponeurosis and pulls scalp posteriorly
Sternocleidomastoid muscle
Major and minor Origins: sternum and clavicle Insertion: mastoid process of temporal bone Action of both: flexes neck Action of one: rotates head
Digastric muscle (THE digastric muscle)
Digastric means has two bellies
Origin: mandible and mastoid process (deep to the mandible, not superficial)
Insertion: hyoid
Action: elevates hyoid, depresses mandible (chewing)
Masseter muscle
Origin: zygomatic arch
Insertion: mandible
Action: elevates mandible - main mover of jaw closure
Splenius muscle
Origin: cervical and thoracic spine
Insertion: occipital bone
Action: extends head and neck
*Deep to the trapezius muscle
Erector spinae muscle
has multiple parts, but we don’t need to get more specific than that
Origin: pelvis and interior spine
Insertion: superior spine and ribs
Action: extends spine
External intercostal muscles
Origins: superior ribs
Insertions: inferior ribs
Action: elevate ribs (inhale)
Internal intercostal muscles
Origins: inferior ribs
Insertions: superior ribs
Actions: depress ribs (exhale)
Rectus abdominis muscle
Origin: anterior pubis
Insertions: xiphoid process and ribs
Action: flexes spine
External oblique muscle
Origin: anterior ribs
Insertion: linea alba and pelvis
Action: flexes and rotates spine
Internal oblique muscle
Origin: lumbar fascia and pelvis
Insertion: linea alba and ribs
Action: flexes and rotates spine (same as external oblique)
Transversus abdominis muscle
Origins: ribs, lumbar fascia, and pelvis
Insertion: linea alba
Action: compresses abdomen
Diaphragm muscle
Origin: inferior border of ribs and sternum
Insertion: central tendon
Action: inspiration
Trapezius muscle
Origins: occipital bone, and cervical and thoracic vertebrae
Insertions: clavicle and scapula
Actions: extends head, moves scapula
Levator scapulae muscle
Origin: cervical vertebrae
Insertion: scapula
Action: elevates scapula
*Deep to trapezius
Rhomboid major and minor muscles
Origins: cervical and thoracic vertebrae
Insertion: scapula
Action: adduct (retract) scapula
*Deep to trapezius
*Both major and minor are inferior to Levator Scapulae
*Minor (thin) is superior to major (thick)
Serratus anterior muscle
Origin: lateral ribs
Insertion: scapula
Action: anchors scapula to ribs (protracts)
*Wraps around the sides of the body to anchor the ribs to the scapula
Pectoralis minor muscle
Origin: anterior ribs
Insertion: scapula
Action: depresses scapula
*Deep to pectoralis major
Pectoralis major muscle
Origins: sternum, ribs, and clavicle
Insertion: humerus
Action: flexes and adducts shoulder
Latissimus dorsi muscle
Origin: thoracic and lumbar vertebrae, and pelvis
Insertion: Humerus
Action: extends and adducts shoulder
Teres major muscle
Origin: inferior scapula
Insertion: humerus
Action: extends and adducts shoulder
Teres minor muscle
Origin: infraspinous fossa of scapula
Insertion: humerus
Action: laterally rotates shoulder
Subscapularis muscle
Origin: subscapular fossa of scapula
Insertion: humerus
Action: medially rotates the shoulder
Supraspinatus muscle
Origin: supraspinous fossa
Insertion: humerus
Action: abducts shoulder
Infraspinatus muscle
Origin: infraspinous fossa
Insertion: humerus
Action: laterally rotates shoulder
Deltoid muscle
Origin: clavicle and scapula
Insertion: deltoid tuberosity of humerus (DELTOID)
Action: abducts, flexes, and extends shoulder
Biceps brachii muscle
Origin: scapula
Insertion: radial tuberosity
Action: flexion of forearm, supination
Brachialis muscle
Origin: anterior humerus
Insertion: coronoid process of ulna
Action: flexes elbow
Triceps brachii muscle
Origins: posterior humerus and scapula
Insertion: olecranon process of ulna
Action: extends elbow
Flexor compartment muscles
Origin: Anterior antebrachium
Insertions: carpals and phalanges
Action: flex wrist and fingers
Extensor compartment muscles
Origin: posterior antebrachium
Insertions: carpals and phalanges
Action: extend wrist and fingers
Gluteus maximus muscle
Origin: posterior pelvis
Insertion: gluteal tuberosity of femur
Action: extends hip
Gluteus medius muscle
Origin: lateral ilium
Insertion: greater trochanter of femur
Action: abducts hip
Tensor fasciae lata muscle
Origin: anterior ilium
Insertion: fascia latte (aka iliotibial tract)
Action: flexes and abducts hip, tenses fascia lata so that the knee and trunk are steady on the thigh
Sartorius muscle
Origin: anterior ilium
Insertion medial tibia
Action: flexes hip and knee
Adductors: Magnus, longus, and brevis
Origin: pubis
Insertion: medial femur
Action: adduct hip
Gracilis muscle
Origin: pubis
Insertion: medial tibia
Action: adducts hip, flexes knee (esp. during walking)
Rectus femoris muscle (quad)
One of the quadriceps muscles
Origin: anterior ilium
Insertion: patellar ligament to tibial tuberosity
Action: extends knee, flexes thigh at hip
*Superficial one of the 4 quadriceps
Vastus lateralis muscle (quad)
Origin: lateral femur
Insertion: patellar ligament to tibial tuberosity
Action: extends knee
Vastus medialis muscle (quad)
Origin: medial femur
Insertion: patellar ligament to tibial tuberosity
Action: extends knee
Vastus intermedius muscle (quad)
Origin: anterior femur
Insertion: patellar ligament to tibial tuberosity
Action: extends knee
Biceps femoris muscle (hamstring)
Origin: ischial tuberosity and femur
Insertions: fibula and lateral tibia
Actions: flexes knee, extends hip
Semitendinosus muscle (hamstring)
Origin: ischial tuberosity
Insertion: medial tibia
Action: flexes knee, extends hip
Semimembranosus muscle (hamstring)
Origin: ischial tuberosity
Insertion: medial tibia
Action: flexes knee and extends hip
Gastrocnemius muscle
Origin: posterior femoral condyles
Insertion: calcaneus (via calcaneal tendon)
Action: plantar flexion, helps flex knee
*Superficial to soleus muscle
Soleus muscle
Origin: posterior fibula and tibia
Insertion: calcaneus (via calcaneal tendon)
Action: plantar flexion
*Deep to gastrocnemius muscle
Fibularis muscles (2)
Origin: fibula
Insertion: lateral tarsals and metatarsals
Actions: plantar flexion and eversion
Tibialis posterior muscles
Origin: posterior tibia
Insertion: medial tarsals
Action: plantar flexion and inversion
*Deep to soleus muscle
Flexor digitorum longus muscle
Origin: posterior tibia
Insertions: phalanges
Action: flexes toes
Tibialis anterior
Origin: anterior tibia
Insertion: tarsus and metatarsus
Action: dorsiflexion
Extensor digitorum longus muscle
Origin: anterior tibia and fibula
Insertions: phalanges
Action: extends toes
