Chp. 13: Gross Anatomy of Muscular Skeleton (Head, Neck, Thorax) Flashcards
Agonists (prime movers)
Muscles responsible for producing a particular movement
Antagonists
Muscles that oppose or reverse a movement
Synergists
Aid the action of agonists by assisting with the same movement or by reducing undesirable or unnecessary movement.
Fixators
Specialization synergists; they immobilize the origin of a prime mover so that all the tension is exerted at the insertion
Rectus
Straight; a muscle with fibers running parallel to the midline
Transverse/ Oblique
Muscles that run at right angles respectively to the midline
Maximus
Largest
Minimus
Smallest
Longus
Long
Brevis
Short
Origin
Stationary, immovable, or less moveable attachment
Insertion
More moveable attachment
Frontal Belly (of Epicranius)
ORIGIN: Epicranial aponeurosis
INSERTION: Skin of eyebrows, root of nose
ACTION: Raises eyebrows
Occipital Belly (of Epicranius)
ORIGIN: Occipital and temporal bones
INSERTION: Epicranial aponeurosis
ACTION: Fixes aponeurosis and pulls scalp posteriorly
Orbicularis Orculi
ORIGIN: Frontal and maxillary bones and ligaments around orbit
INSERTION: Tissue of eyelid
ACTION: Closes Eye
Zygomaticus (major and minor)
ORIGIN: Zygomatic bone
INSERTION: Skin and Muscle at corner of mouth
ACTION: Raises lateral corners of mouth upward (smile)
Orbicularis Oris
ORIGIN: Arises indirectly from maxilla and mandible; fibers blended with fibers of other muscles associated with lips
INSERTION: Encircles mouth; inserts into muscle and skin at angles of mouth
ACTION: Closes lips
Buccinator
ORIGIN: Molar Region of Maxilla and Mandible
INSERTION: Orbicularis Oris
ACTION: Compresse Cheek
Masseter
ORIGIN: Zygomatic Arch
INSERTION: Angle and Ramus of mandible
ACTION: Prime mover of jaw closure
Temporalis
ORIGIN: Temporal Fossa
INSERTION: Coronoid Process of Mandible
ACTION: Closes Jaw
Platysma
ORIGIN: Fascia of Chest (over pectoral muscles) and deltoid
INSERTION: Lower Margin of mandible, skin, and muscle at corner of mouth.
ACTION: Tenses skin of neck
Sternocleidomastoid
ORIGIN: Manubrium and Medial portion of clavicle
INSERTION: Mastoid process of temporal bone and superior nuchal line of occipital bone
ACTION: Flexion of neck, rotate head toward shoulder on opposite side
Sternohyoid
ORIGIN: Manubrium and medial end of clavicle
INSERTION: Lower margin of hyoid bone
ACTION: Depresses larynx and hyoid bone
Pectoralis Major
ORIGIN: Clavicle, sternum, cartilage of ribs 1-6, and aponeurosis of external oblique muscle
INSERTION: Fibers converge to insert by short tendon into intertubercular sulcus of humerus
ACTION: Prime mover of arm flexion; adducts, medially rotates arm
Serratus Anterior
ORIGIN: Lateral aspect of ribs 1-8
INSERTION: Vertebral border of anterior surface of scapula
ACTION: Prime mover to protract and hold scapula against chest wall; rotates scapula
Pectoralis Minor
ORIGIN: Anterior surface of ribs 3-5, near their costal cartilages
INSERTION: Coracoid process of scapula
ACTION: With ribs fixed, draws scapula forward and inferiorly
External Intercostals
ORIGIN: Inferior border of rib above
INSERTION: Superior border of rib below
ACTION: Pulls ribs toward one another to elevate rib cage (aids in inspiration)
Internal Intercostals
ORIGIN: Superior border of rib below
INSERTION: Inferior border of rib above
ACTION: Draws ribs together to depress rib cage
Diaphragm
ORIGIN: Inferior border of rib and sternum, costal cartilages of last six ribs and lumbar vertebrae
INSERTION: Central tendon
ACTION: Prime mover of inspiration flattens on contraction
Rectus Abdominus
ORIGIN: Pubic crest and symphysis
INSERTION: Xiphoid process and costal cartilages of ribs 5-7
ACTION: Flexes and rotates vertebral column
External Oblique
ORIGIN: Anterior surface of lower eight ribs
INSERTION: Linea alba, pubic crest and tubercles, and illiac crest
ACTION: See rectus abdominus, compresses abdominal wall, trunk rotation and lateral flexion
Internal Oblique
ORIGIN: Lumbar fascia, illiac crest, and inguinal ligament
INSERTION: Linea alba, pubic crest, and costal cartilages of last three ribs
ACTION: As for external oblique
Transverse Abdominis
ORIGIN: Inguinal ligament, iliac crest, cartilages of last five ribs, and lumbar fascia
INSERTION: Linea alba and pubic crest
ACTION: Compresses abdominal contents
Trapezius
ORIGIN: Occipital bone; ligamentum nuchae; spines of C7 and all thoracic vertebrae
INSERTION: Acromion and Spinous process of scapula; lateral third of clavicle
ACTION: Raises, rotates, and retracts (adducts) scapula and stabilizes it
Latissimus dorsi
ORIGIN: Indirect attachment to spinous process of lower six thoracic vertebrae, lumbar vertebrae, last three ribs, illac crest
INSERTION: Floor of intertubercular sulcus of humerus
ACTION: Prime mover of arm extension; adducts and medially rotates arm
Levator Scapulae
ORIGIN: Transverse processes of C1-C4
INSERTION: Medial border of scapula superior to spine
ACTION: Elevates and adducts scapula
Rhomboids (major and minor)
ORIGIN: Spinous processes of C7 and T1-T5
INSERTION: Medial border of scapula
ACTION: Stabilizes scapulae
Erector Spinae (Iliocostals, Longissimus, and Spinalis muscle columns)
ORIGIN: Iliac crest, transverse processes of lumbar, thoracic, and cervical vertebrae, and/or ribs 3-6 depending on specific part
INSERTION: Ribs and transverse processes of vertebrae about six segments above origin; longissimus also inserts into mastoid process
ACTION: Extend and bend the vertebral column laterally; fibers of the longissimus also extend and rotate head
Quadratus lumborum
ORIGIN: Iliac crest and lumbar fascia
INSERTION: Inferior border of rib 12; transverse processes of lumbar vertebrae
ACTION: Each flexes vertebral column laterally
