Individual Skeletal Muscles Flashcards
Temporalis
Origin: temporal bone
Insertion: coronoid process and ramus of mandible
Action: elevates and retracts mandible
Orbicularis oculi
Origin: medial wall of orbit
Insertion: circular path around orbit
Action: closes eye
Masseter
Origin: maxilla and zygomatic arch
Insertion: angle and ramus of mandible
Action: elevates mandible
Buccinator
Origin:alveolar processes of maxilla and mandible and pterygomandibular raphe
Insertion: orbicularis oris
Action: presses cheeks against teeth, draws corner of mouth laterally, assists in mastication
Zygomaticus major
Origin: zygomatic bone
Insertion: skin at angle of mouth and orbicularis oris
Action: draws angle of mouth superior and lateral, smiling
Zygomaticus minor
Origin: zygomatic bone
Insertion: upper lip
Action: raises upper lip exposing upper teeth
Orbicularis oris
Origin: muscle fibers surrounding opening of mouth
Insertion: skin at corner of mouth
Action: closes and protrudes lip kissing, compresses lip against teeth, shapes lips during speech
Sternocleidomastoid
Origin: sternal head, manubrium, clavicular head, medial clavicle
Insertion: mastoid process of temporal, lateral superior nuchal line of occipital
Action: bilaterally flex cervical portion of neck, extend head at joint. Unilaterally laterally flex head and neck to side and rotate
Platysma
Origin: facia over deltoid and pectoralis major muscles
Insertion: mandible
Action: tenses skin of neck, draws outer part of lower lip inferior and posterior as in pout, depresses mandible
Trapezius
Origin: superior nuchal line of occipital and c7 to t12
Insertion: clavicle and acromion and spine of scapula
Action: upward rotate scapula, adduct scapula, stabilize scapula
Deltoid
Origin: acromial of clavicle and scapula, spine of scapula
Insertion: deltoid tuberosity of humerus
Action: abduct arm, flex and medially rotate arm, extend and laterally rotate arm
Supraspinatus
Origin: supraspinous fossa of scapula
Insertion: greater tubercle of humerus
Action: assist deltoid in abducting arm
Infraspinatus
Origin: infraspinous fossa of scapula
Insertion: greater tubercle of humerus
Action: laterally rotate arm
Teres major
Origin: inferior angle of scapula
Insertion: medial lip of intertubercular sulcus of humerus
Action: extend arm, assist in adduction and medial rotation of arm
Teres minor
Origin: inferior lateral border of scapula
Insertion: greater tubercle of humerus
Action: laterally rotate and extend arm
Rhomboid major, minor
Origin: major t2 to t5, minor c7 to t1
Insertion: vertical border of scapula inferior to spine
Action: stabilize scapula, elevates and adducts scapula and rotates down
Latissimus dorsi
Origin: t7 to l5, sacrum, ilium, ribs 9-12
Insertion:intertubercular sulcus of humerus
Action: extends, adducts, medially rotates arm, draws arm inferior and posterior
Triceps brachii
Origin: scapula, humerus, humerus
Insertion: olecranon
Action: extends forearm at elbow, arm
Biceps brachii
Origin: scapula above glenoid, coracoid process of scapula
Insertion: radial tuberosity, bicipital aponeurosis
Action: flexes forearm, supinates forearm, flexes arm
Brachialis
Origin: distal anterior humerus
Insertion: ulnar tuberosity and coronoid process of ulna
Action: flexes forearm
Brachioradialis
Origin: lateral distal humerus
Insertion: superior to styloid process of radius
Action: flexes forearm, supinates and pronates forearm to neutral