Axial Musculature Flashcards
Temporalis
Muscle of mastication: elevates mandible and closes jaw
Masseter
Muscle of mastication: elevates mandible and closes jaw - if you clench jaw, it’s the muscle that bulges out
Lateral pterygoid
Muscle of mastication: opens jaw, protrudes mandible and moves mandible from side to side
Medial pterygoid
Muscle of mastication: elevates mandible, closes jaw and moved mandible side to side
Skeletal muscles are divided into two groups (associated with?)
Axial musculature: associated with axial skeleton
Appendicular musculature: associates with appendicular skeleton
Axial musculature - main purposes (5)
Vision, mastication, facial expression and swallowing. Upright posture and movement of the back. Support if abdominal and pelvic viscera. Respiration. Urination, defecation and parturition.
Appendicular musculature - main purposes (2)
Stabilizes the pectoral and pelvic girdles. Moves upper and lower limbs.
Four groups of axial muscles
Head and neck: face, oral cavity, pharynx, larynx. Back: flexes and extenders of axial skeleton. Thorax and abdominopelvic cavity: forms wall of thoracic and abdominopelvic cavities. Pelvic floor: extend between sacrum and pelvic girdle to form muscular perineum.
Muscles of mastication (4)
Temporalis. Masseter. Lateral pterygoid. Medial pterygoid.
Muscles of facial expression (6)
Orbicularis oculi. Obicularis pros. Platysma. Buccinator. Occipitofrontalis. Epicranial aponeurosis.
Orbicularis oculi
Muscles of facial expression : closes eye, squinting
Orbicularis oris
Muscles of facial expression : constricts opening of mouth
Platysma
Muscles of facial expressions : tenses skin if neck - just under skin, very thin muscle “shaving muscle”
Buccinator
Muscles of facial expression : moves food across teeth, suction - ribbon like
Occipitofrontalis (frontal belly)
Muscles of facial expressions : raises eyebrows as wrinkles forehead
Occipitofrontalis
Muscles of facial expressions : tenses and retracts scalp
Extraocular muscles
Associated with the eye: have to be very precise so has many small units - ribbon like muscles
Extra ocular muscle types (7)
A
Levator palpebrae eyelid
Opens upper eyelid
Rectus …
4 rectus muscles : move eye up down left right - for eye to look straight and be I equilibrium, all muscles are gently pulling equally
Palsy
Old word for paralysis
Temporalis and masseter in closing jaw
Masseter: very powerful, Primary agonist. Temporalis: convergent so not as much force, synergist
Muscles of facial expression origin bad insertion
Origin : skull. Insertion : skin
Epicranial aponeurosis
Flat white broad tendon that connects frontal and occipital belly of occipitofrontalis - forms most if scalp