Muscles Flashcards
Temporalis
Origin: temporal fossa
Insertion: coronoid process of mandible
Action: elevates mandible
Occipitalis
Origin: lateral 2/3 of superior nuchal line external protuberance
Insertion: galea aponeurosis
Action: draws back the scalp to raise eyebrows and wrinkle the brow
Frontalis
Origin: frontal bone
Insertion: skin of the eyebrows
Action: wrinkle eyebrows, forehead elevation, raise eyebrows
Masseter
Origin: zygomatic process and its arch
Insertion: angle and ramus of mandible
Action: bilateral- elevates mandible
unilateral- laterally moves mandible
Buccinator
Origin: molar region of maxilla and mandible
Insertion: orbicularis oris muscle
Action: draw corners of mouth laterally (whistling muscle)
Orbicularis Oris
Origin: maxilla and mandible
Insertion: encircles mouth
Action: closes mouth (kissing muscle)
Medial Pterygoid
Origin: medial surface of lateral Pterygoid plate of sphenoid palatine bone Pterygoid fossa
Insertion: inner surface of mandibular ramus and angle
Action: elevates mandible, protrudes mandible with lateral pterygoid
Lateral Pterygoid
Origin: superior head- lateral surface of sphenoid greater wing
Inferior head- lateral surface of the lateral Pterygoid plate
Insertion: neck of the mandibular consuls, TMJ articular disc
Action: unilateral- deviates mandible opposite of attraction
Bilateral- depresses mandible
Sternocleidomastoid (SCM)
Origin: anterior and superior manubrium and superior medial third of clavicle
Insertion: lateral aspect of mastoid process and anterior half of superior nuchal line
Action: unilateral- flexes head same side, rotates head opposite side
bilateral- flexes neck
Anterior Scalene
Origin: C3 to C6 transverse processes
Insertion: 1st ribs
Action: unilateral- flexes head same side, rotates head opposite side
bilateral- elevates ribs, flexes head
Medial scalene
Origin: C2 to C7 transverse processes
Insertion: 1st ribs
Action: unilateral- flexes head same side, rotates head opposite side
bilateral- elevated ribs
Posterior scalene
Origin: C4 to C6 transverse processes
Insertion: 2nd ribs
Action: unilateral- flexes head same side, rotates head opposite side
bilateral- elevated ribs
Splenius capitus
Origin: C7 to T3 spinous process and nuchal ligament
Insertion: superior nuchal line and mastoid process
Action: unilateral- rotates head same side, flexes neck
bilateral- extends head
Splenius cervicus
Origin: T3-T6 spinous processes
Insertion: C1-C3 transverse processes
Action: unilateral- rotates head to same side, laterally flexes neck
bilateral- extends head
Levator Scapulae
Origin: C1 to C4 transverse processes
Insertion: superior angle of scapula
Action: unilateral- elevates, downwardly rotates scapula, laterally flexes neck
bilateral: extends head
Erector Spinae Group
Spinalis (most medial)
Longissimus (middle)
Illiocostalis (most lateral)
Action: unilateral- lateral flexion of spine
bilateral- extension of spine
Transversospinalis Group
Multifidi
Rotatores
Semispinalis capitus
Deep to erector spinae group
Multifidus
Origin: transverse process of one vertebrae
Insertion: sacrum and spinous process of all vertebrae extending 2-4 higher
Action: bilateral- extends vertebral column
unilateral- rotate to opposite side, flex to same side
Rotatores
Origin: transverse process of one vertebra
Insertion: spinous process of vertebra 1-2 above origin
Action: unilateral- rotate to opposite side
bilateral- extension
Semispinalis capitus
Origin: transverse process of C4 to T5
Insertion: between superior and inferior nuchal lines of occipital bone
Action: extend vertebral column
Intercostal Muscles
External
Internal
Innermost
Action: elevation and depression of ribs during breathing
Pectoralis Major
Origin: clavicular head- medial half of clavicle
sternum head- sternum, upper costal cartilages, aponeurosis of external obliques
Insertion: lateral lip of intertubercular groove and crest of greater tubercle of humerus
Action: clavicular- flex arm
sternal- extends arm
both- medially rotate and adduct arm
Pectoralis Minor
Origin: ribs 3-5 near costal cartilage
Insertion: medial border and superior surface of corocoid process of scapula
Action: stabilizes scapula, pulls it inferior and anterior against posterior rib cage
Abdominal Group
Rectus abdominis
External oblique
Internal oblique
Transverse abdominis
Rectus abdominis
Origin: pubic crest and symphysis
Insertion: ribs 5-7 and xiphoid process
Action: trunk flexion, accessory respiratory muscle
External obliques
Origin: lower 8 ribs at costal cartilages
Insertion: crest of ilium, linea alba through rectus sheath
Action: unilateral- flex vertebral column to opposite side
bilateral- flexes spine
Internal obliques
Origin: inguinal ligament, iliac crest, thoracolumbar fascia
Insertion: internal surfaces of lower 3 ribs, linea alba, abdominal aponeurosis
Action: unilateral- lateral flexion to same side
bilateral- flexes spine
Transverse abdominis
Origin: cartilage of lower 6 ribs, thoracolumbar fascia, iliac crest, inguinal ligament
Insertion: linea alba through rectus sheath, pubic symphysis and xiphoid process
Action: compresses abdominal viscera
Diaphragm
Origin: inner surface of ribs 7-12, L2 and L3, inner xiphoid process
Insertion: central tendon
Action: inhale- flattens
exhale- domes back upward
Trapezius
Origin: occipital bone, nuchal ligament, spinous process of C7-T12
Insertion: Lateral third of clavicle, acromian, spine of scapula
Action: upper- bilaterally extends neck; unilaterally flexes neck same side, rotates head opposite side, elevates and upwardly rotates scapula
Middle- adducts and stabilizes scapula
lower- depresses amd upwardly rotates scapula
Rhomboid Minor
Origin: spinous processes of C7-T1, lower part of nuchal ligament
Insertion: medial margin of the scapula at the root of the spine
Action: adducts, elevates, rotates scapula
Rhomboid Major
Origin: spinous processes of T2-T5
Insertion: medial margin of scapula between spine and inferior angle
Action: retracts, elevates, and downwardly rotates scapula
Latissimus Dorsi
Origin: T6-T12, last 3-4 ribs, posterior iliac crest and thoracolumbar aponeurosis
Insertion: intertubercle groove and crest of lesser tubercle of humorus
Action: extension of trunk, adduction and internal rotation at the shoulder
Serratus Anterior
Origin: upper anterior surface of ribs 1-8
Insertion: costal aspect of medial border scapula
Action: protract and stabilize scapula, assist in upward rotaion
Serratus Posterior
deep back muscles, located in upper and lower parts of the back
Supraspinatus
Origin: supraspinous fossa of scapula
Insertion: greater tubercle of humerus
Action: abduct shoulder to 45°, stabilize humerus in glenoid fossa
DOES NOT ROTATE
Infraspinatus
Origin: Infraspinatus fossa of scapula
Insertion: greater tubercle of humerus
Action: external rotation, adduction, extension, horizontal abduction, stabilize humerus in glenoid fossa
Teres Minor
Origin: upper 2/3 of lateral border of scapula
Insertion: greater tubercle of humerus
Action: external rotation, adduction, extension, horizontal abduction, stabilize humerus in glenoid fossa
Subscapularus
Origin: subscapular fossa of scapula
Insertion: lesser tubercle of humerus
Action: internal rotation, stabilize humerus in glenoid fossa
Deltoid (anterior)
Origin: outer 1/3 of clavicle
Insertion: deltoid tuberosity
Action: flexion, internal rotation, horizontal adduction
Deltoid (medial)
Origin: boarder of acromion
Insertion: deltoid tuberosity
Action: abduction
Deltoid (posterior)
Origin: scapular spine
Insertion: deltoid tuberosity
Action: extension, external rotation, horizontal abduction
Teres Major
Origin: inferior angle and lower 1/2 of lateral border of scapula
Insertion: intertubercular groove of humerus
Action: adduction, internal rotation, extension
Biceps Brachii
Origin: short head- coracoid process
Long head- supraglenoid tubercle
Insertion: tuberosity of the radius and aponeurosis of biceps brachii
Action: elbow flexion, forearm supination, shoulder flexion
Triceps Brachii
Origin: long head- infraglenoid tubercle
Lateral head- posterior surface of proximal half of humerus
Medial head- posterior surface of distal half of humerus
Insertion: olecranon process of radius
Action: elbow extension, shoulder extension and adduction
Coracobrachialis
Origin: coracoid process
Insertion: medial surface of humerus
Action: shoulder flexion and adduction
Brachialis
Origin: lower half of humerus on anterior side
Insertion: coranoid process of ulna
Action: elbow flexion in all positions
Brachioradialis
Origin: lateral supracondylar ridge of humerus
Insertion: radial styloid process
Action: elbow flexion when thumb is pointed up (hammer muscle)
Anconeus
Origin: lateral epicondyle of humerus
Insertion: layers aspect of olecranon process
Action: elbow extension
Pronator Quadratus
Origin: anterior surface of distal ulna
Insertion: anterior surface of distal radius
Action: pronation
Pronator Teres
Origin: distal humerus on medial side and proximal ulna
Insertion: middle of the lateral surface of the radius
Action: forearm pronation, elbow flexion
Supinator
Origin: lateral epicondyle of humerus, Supinator crest of ulna
Insertion: superior and lateral radius
Action: supination
Flexor Carpi Radialis
Origin: medial epicondyle of humerus
Insertion: anterior base of second metacarpal
Action: wrist flexion and abduction
Flexor Carpi Ulnaris
Origin: medial epicondyle of ulna and medial margin of olecranon
Insertion: pisiform, hamate, base of fifth metacarpal
Action: wrist flexion and adduction
Palmaris Longus
Origin: medial epicondyle of humerus
Insertion: palmar aponeurosis, flexor retinaculum of the hand
Action: wrist flexion
