Anatomy Flashcards
What can the muscles of the face be divided into?
Muscles of facial expression
Muscles of mastication
What nerve innervates the muscles of facial expression?
CN VII - facial
What nerve innervates the muscles of mastication?
CN V - trigeminal
What are the main muscles in the neck?
Platysma Trapezius Sternocleidomastoid Scalene muscles Supra-hyoids Infra-hyoids
What nerves innervate the supra-hyoids?
Cranial nerves
What nerves innervate the infra-hyoids?
Cervical nerves
What is the origin of platysma?
Fascia of pec major and deltoid
What in the insertion of platysma?
Inferior mandible
What is the action of platysma?
Depresses and wrinkles skin of lower face and mouth
Aids in opening jaw
What in the innervation of platysma?
CN VII - facial
What is the origin of trapezius?
Skull
Nuchal ligament
Spinous processes C7-T12
What is the insertion of trapezius?
Clavicle
Acromion
Scapula spine
What is the action of trapezius?
Upper fibres = elevate scapula
Middle fibres = retract scapula
Lower fibres = pull scapula inferiorly
What is the innervation of trapezius?
Spinal accessory nerve
What is the origin of SCM?
Anterosuperior manubrium + medial 1/3 of clavicle
What is the insertion of SCM?
Mastoid process
What is the action of SCM?
Flex + laterally rotate cervical spine
What is the innervation of SCM?
Spinal accessory nerve
What are the scalene muscles?
3 paired muscles located in the lateral neck
What is the origin of the scalene muscles?
Anterior = anterior tubercles of transverse processes C3-6
Middle = posterior tubercles of transverse processes C2-7
Posterior = posterior tubercles of transverse processes C5-7
What is the insertion of the scalene muscles?
Anterior = scalene tubercle on 1st rib
Middle = scalene tubercle on 1st rib
Posterior = 2nd rib
What is the action of the scalene muscles?
Anterior = elevation of 1st rib
Middle = elevation of 1st rib
Posterior = elevation of 2nd rib
What is the innervation of the scalene muscles?
Anterior = anterior rami C5-6
Middle = anterior rami C3-8
Posterior = anterior rami C6-8
What muscles make up the supra-hyoids?
Stylohyoid
Digastric
Mylohyoid
Geniohyoid
What is the action of the supra-hyoids?
Elevate the hyoid bone - action involved in swallowing
What muscles make up the infra-hyoids
Omohyoid
Sternohyoid
Sternothyroid
Thyrohyoid
What is the action of the infra-hyoids?
Depress hyoid bone
Apart from sternothyroid - depresses thyroid cartilige
What are the main areas in the neck?
Anterior triangle
Posterior triangle
What are the borders of the anterior triangle?
Superior = mandible
Lateral = anterior border SCM
Medial = sagittal line
What are the contents of the anterior triangle?
Supra-hyoid muscles
Infra-hyoid muscles
Common carotid artery
Internal jugular vein
CN VII - facial CN IX - glossopharyngeal CN X - vagus CN XI - accessory CN XII - hypoglossal
What can the anterior triangle be divided into?
Carotid triangle
Submental triangle
Submandibular triangle
Muscular triangle
What are the borders of the carotid triangle?
Superior = posterior belly of digastric muscle
Lateral = medial border of SCM
Inferior = superior belly of omohyoid muscle
What are the contents of the carotid triangle?
Common carotid artery - bifurcates within triangle
Internal jugular vein
CNXII - hypoglossal
CNX - vagus
What are the borders of submental triangle?
Inferior = hyoid bone
Medial = midline of neck
Lateral = anterior belly of digastric
What are the contents of the submental triangle?
Submental lymph nodes
What are the borders of the submandibular triangle?
Superior = mandible
Anterior = anterior belly of digastric
Posterior = posterior belly of digastric
What are the contents of the submandibular triangle?
Submandibular salivary gland
Lymph nodes
Facial artery
Facial vein
What are the borders of the muscular triangle?
Superior = hyoid bone
Medial = midline of neck
Supero-lateral = superior belly of omohyoid
Infero-lateral = inferior SCM
What are the borders of the posterior triangle?
Anterior = posterior SCM
Posterior = trapezius
Inferior = middle 1/3 clavicle
What are the contents of the posterior triangle?
Muscles
- omohyoid
- scalenes
Veins
- external jugular
- subclavian
- transverse cervical
- suprascapular
Artery
- subclavian
Nerves
- CNXI - accessory
What splits the posterior triangle?
Inferior belly of omohyoid
What is the posterior triangle split into?
Occipital triangle
Subclavian triangle
What are the fascias in the neck?
Deep cervical fascia
Superficial cervical fascia
Where does the superficial cervical fascia lie?
Between the dermis and deep cervical fascia
What are the contents of the superficial cervical fascia?
Neurovascular supply to the skin
Superficial veins
Superficial lymph nodes
Fat
Platysma
What are the layers of the deep cervical fascia?
Investing layer
Pretracheal layer
Prevertebral layer
Carotid sheath
What is the investing layer?
Surrounds all the structures in the neck - when it mees trapezius and SCM surrounds them
What are the attachments of the investing layer?
Superior = external occipital protuberance + superior nuchal line
Anterior = hyoid
Inferior = spine/acromion of scapula, clavicle, manubrium
Posterior = nuchal ligament
What is the pretracheal layer?
Layer of fascia in anterior neck between hyoid bone and pericardium
What is enclosed by the pretracheal layer?
Trachea
Oesophagus
Thyroid
Infrahyoid muscles
What is the prevertebral layer?
Surrounds the vertebral column and its associated muscles
What is the carotid sheath?
Formed by continuations of the investing, pretracheal and prevertebral layers
What are the contents of the carotid sheath?
Common carotid artery
Internal jugular vein
Vagus nerve
Cervical lymph nodes
What happens in the carotid sheath?
Carotid artery bifurcates
How are the muscles of facial expression divided?
Orbital
Nasal
Oral
What are the orbital muscles of facial expression?
Orbicularis oculi - closes eyes
Corrugator supercilii - draws eyebrows together
What are the nasal muscles of facial expression?
Nasalis - open/close nostrils
Procerus - pulls eyebrow down
Depressor septi nasi - opens nostril
What are the oral muscles of facial expression?
Orbicularis oris - purses lips
Buccinator - pulls cheek inwards towards teeth
What are the muscles of mastication?
Masseter
Temporalis
Medial pterygoid
Lateral pterygoid
What are the action of muscles of mastication?
Elevate the mandible