mblex

Action: raises eyebrows

Origin: galea aponeurotica

Insertion: eyebrow skin, bridge of nose

Frontalis

Action: closes jaw; elevates mandible

Origin: zygomatic arch

Insertion: mandibular ramus

Masseter

Action: pulls scalp posteriorly

Origin: galea aponeurotica {thin sheet of connective tissue}

Insertion: galea aponeurotica {thin sheet of connective tissue}

Occipitalis

Action: closes, blinks and squints eyes

Origin: medial margin of orbit

Insertion: skin around eyelids

Orbicularis Oculi

Action: closes mouth; kissing muscle

Origin: maxilla and mandible

Insertion: lips

Orbicularis Oris

Action: rotates head, head flexion

Origin: clavicle and manubrium of sternum

Insertion: mastoid process of temporal bone

Sternocleidomastoid

Action: depresses larynx and hyoid bone

Origin: clavicle and manubrium of sternum

Insertion: hyoid bone

Sternohyoid

Action: elevates ribs

Origin: inferior border of each rib

Insertion: superior border of each rib

External Intercostals

Action: closes jaw, elevates mandible

Origin: temporal bone

Insertion: coronoid process of mandible

Temporalis

Action: retracts and elevates upper lip

Origin: zygomatic bone

Insertion: skin on lateral sides of the mouth

Zygomaticus

Action: flexion, adduction, and medial rotation at shoulder

Origin: ribs 2-6, sternum, and clavicle

Insertion: greater tubercle of humerus

Pectoralis Major

Action: protracts scapula

Origin: ribs 3-5

Insertion: coracoid process of scapula

Pectoralis Minor

Action: adducts scapula

Origin: spinous processes of vertebrae

Insertion: vertebral border of scapula

Rhomboid Major

Action: protracts scapula

Origin: ribs 1-8

Insertion: vertebral border of scapula

Serratus Anterior

Action: extends neck; elevate or retract scapula

Origin: occipital bone and spinous processes of cervical and thoracic vertebrae

Insertion: clavicle and scapula

Trapezius

Action: elevates ribs

Origin: inferior border of each rib

Insertion: superior border of each rib

External Intercostals

Action: depresses ribs

Origin: superior border of each rib

Insertion: inferior border of each rib

Internal Intercostals

Action: abduction at shoulder

Origin: clavicle and scapula

Insertion: deltoid tuberosity of humerus

Deltoid

Action: extension, adduction, and medial rotation at shoulder

Origin: spinous processes of inferior thoracic and all lumbar vertebrae

Insertion: intertubercular groove of humerus

Latissimus Dorsi

Action: lateral rotation at shoulder

Origin: infraspinous fossa of scapula

Insertion: greater tubercle of humuerus

Infraspinatus

Action: Abduction at shoulder

Origin: supraspinous fossa of scapula

Insertion: greater tubercle of humerus

Supraspinatus

Action: extension, adduction, and medial rotation at shoulder

Origin: scapula

Insertion: intertubercular groove of humerus

Teres Major

Action: medial rotation at shoulder

Origin: subscapular fossa of scapula

Insertion: lesser tubercle of humerus

Subscapularis

Action: flexion at elbow and shoulder, supination

Origin: coracoid process of scapula, and tubercle above the glenoid cavity of the scapula

Insertion: tuberosity of radius

Biceps Brachii

Action: extension at elbow

Origin: Three heads: scapula (1) and posterior humuerus (2)

Insertion: olecranon of ulna

Triceps Brachii

Action: flexion at elbow

Origin: anterior distal humerus

Insertion: tuberosity of ulna

Brachialis

Action: flexion at elbow

Origin: ridge above lateral epicondyle of humerus

Insertion: styloid process of radius

Brachioradialis

Action: pronation

Origin: medial condyle of humerus and coronoid process of ulna

Insertion: radius

Pronator Teres

Action: flexion and abduction at wrist

Origin: medial epicondyle of humerus

Insertion: base of 2nd and 3rd metacarpals

Flexor Carpi Radialis

Action: flexion at wrist

Origin: medial epicondyle of humerus

Insertion: palmar aponeurosis

Palmaris Longus

Action: flexion and adduction at wrist

Origin: medial epicondyle of humerus

Insertion: 5th metacarpal

Flexor Carpi Ulnaris

Action: extension at finger joints and wrist

Origin: lateral epicondyle of humerus

Insertion: fingers 2-5

Extensor Digitorum

Action: extension and adduction at wrist

Origin: lateral epicondyle of humerus

Insertion: base of 5th metacarpal

Extensor Carpi Ulnaris

Action: extension and abduction at wrist