H&N Fascia & Musculature Flashcards
S.C.A.L.P. layers
Skin
Connective tissue
Aponeurosis
Loose areolar tissue
Pericranium
{Skin, connective tissue, and aponeurosis are the first three layers that are intimately connected and move as a unit}
Skin
thin layer containing hair follicles, and sweat and sebaceous glands
Connective tissue
thick, dense, and richly vascular subcutaneous layer with cutaneous nerves
Aponeurosis
flat, broad, strong tendon that serves as muscle attachment
Loose areolar tissue
sponge-like, allows free movement of above 3 layers. May swell due to infection or injury
Pericranium
dense layer of connective tissue forming the outer membrane of cranium (periosteum)
What are the layers of the neck?
skin
platysma
superficial fascia
deep fascia
Platysma
broad, thin sheet of muscle. Covers anterolateral part of neck. External jugular vein and main cutaneous nerves of neck are deep to the platysma; mm men use to shave
Superficial fascia
layer of fatty subcutaneous tissue surrounding the whole neck. Located between skin and investing layer of deep cervical fascia
Deep fascia
- Allow separation of tissue during surgery, and limit spread of infection.
- Permit sliding of structures pass over one another without difficulty
- several layers that compartmentalize structures in the neck:
- Investing; surrounding whole neck in red
- Pretracheal;
- Prevertebral spinal cord and mm
- Carotid sheath anterior portion, where the trachea, esophagus, major vessels (vagus nerve and carotid)
Investing?
attachments?
Investing: encircles the entire neck deep to superficial fascia
- Superior attachment
- Superior nuchal line of the OB
- Mastoid process of the TB
- Zygomatic arches
- Inferior border of mandible
- Hyoid bone
- Spinous process of cervical vertebrae
- Inferior attachment
- Manubrium
- Clavicles
- Acromions and spines of scapula
Pretracheal
Pretracheal: surrounds structures in the anterior part of neck
- Attachments: extends from hyoid bone to thorax, where it blends with pericardium
- Muscular part: encloses infrahyoid muscles
- Visceral part: encloses thyroid gland, trachea, esophagus, and pharynx
- Buccopharyngeal fascia: posterior continuation of visceral part of pretracheal layer; little portion in green on figure
Prevertebral
surrounds vertebral column and associated muscles
- Attachments: extends from cranial base superiorly and blend inferiorly to the endothoracic fascia, communicating with the mediastinum
Carotid sheath
surrounds common and internal carotid aa., internal jugular v., and vagus n. (CN X); seen in brown in fig. below
- Attachments: extends from cranial base to root of neck, where it communicates with the mediastinum
layers that contribute to the formation of the carotid sheath?
Investing, pretracheal, and prevertebral layers contribute to the formation of the carotid sheath
Alar fascia
thin layer of fascia
- Attachments: extends from cranial base to root of neck
- Attached at the midline to buccopharyngeal fascia and laterally to carotid sheath
Retropharyngeal space
interfascial space between pretracheal (anteriorly), prevertebral (posteriorly), and carotid sheaths (laterally); area in black box
general characteristis of mm of facial expression
- Located in subcutaneous tissue of scalp, face, and neck
- Move skin and change facial expression to convey mood
- Attachment originates from deep fascia and bone and insert on skin
- Innervation by the facial nerve (CN VII)
- Muscles
- Scalp and forehead
- Mouth, lips, and cheeks
- Eyes, ear, and nose
what is the major MOTOR nerve to the head
Facial nerve (CN VII)
makes the mm move
mm of forehead & scalp
frontalis
occipitalis
frontalis
- Attachment: skin of eyebrows and root of nose
- Function: elevates eyebrow and wrinkles forehead
Occipitalis
- Attachment: the lateral 2/3rds of the superior nuchal line
- Function: draws scalp back and wrinkles back of head
frontalis and occipitalis is connected by?
galea APONEUROTICA
Muscles of mouth, lips, and cheeks
- Levator labii superioris
- Zygomaticus major
- Depressor anguli oris
- Depressor labii inferioris
- Platysma
- Levator anguli oris
- buccinator
- orbicularis oris
Levator labii superioris
- A: from infraorbital margin to skin of upper lip
- F: elevates upper lip
Zygomaticus major
- A: zygomatic bone to angle of mouth
- F: elevates the corner of mouth
Depressor anguli oris
- A: anterolateral base of mandible to angle of mouth
- F: depresses corner of mouth
Depressor labii inferioris
- A: from mandible to skin of lower lip
- F: depresses lower lip
Platysma
- A: from fascia and skin over clavicular region to base of mandible, angle of mouth, lower part of face
- F: depresses mandible, tenses skin of inferior face and neck
Levator anguli oris
- Deep to levator labii superioris m, and accessory muscle to zygomaticus major
- A: from maxilla (just below infraorbital foramen) to angle of mouth
- F: elevates corner of the mouth
Buccinator (not involved in mastication)
- Deep to the Masseter. Forms principal substance of cheeks
- A: anteriorly angle of mouth and posteriorly to mandible, maxilla, and pterygomandibular raphe tendon, a tendinous extension of buccopharyngeal fascia.
- F: mastication (keeps cheeks taut), smiling
Orbicularis oris
- A: encircles mouth and attaches into upper and lower lips. Oral sphincter
- F: Articulation and mastication
Muscles of eyes
orbicularis oculi
Orbicularis oculi
- A: Circular muscle around orbital margin into eyelids, sphincter of eyes
- F: Closes orbital opening, encourages flow of tear by helping empty lacrimal sack
muscles of the ear
- Auricularis anterior
- Auricularis posterior
- Auricularis superior
- A: skin of the auricle of ear
muscles of the nose
Procerus
nasalis
depressor septi
Procerus
- A: from forehead to skin over bridge of nose
- F: depresses medial angle of eyebrows (when very serious)
Temporalis
- Occupies temporal fossa
- A: from temporal fossa to coronoid process of mandible
- F: elevation, retraction, lateral excursion of mandible
Masseter (superficial to the buccinator)
- Very strong, thick muscle
- A: zygomatic arch to lateral surface of ramus and angle of mandible
- F: elevation, and protraction of mandible, clenches teeth
Medial pterygoid
- Located in the infratemporal fossa.
- A: from lateral pterygoid plate and maxillary tuberosity to medial (or internal) surface of ramus and angle of mandible
- F: elevation, protraction, and lateral excursion of mandible. Synergistic with masseter m.
Lateral pterygoid
- Deep in the temporal fossa. Short, strong, and runs horizontally
- A: lateral pterygoid plate and greater wing of sphenoid to neck of mandible and penetrating the TMJ capsule inserts on the articular disc
- F: depression, protraction, and lateral excursion of mandible
Sternocleidomastoid (SCM)
- Bisects the neck diagonally
- A: from mastoid process and lateral 1/2 of superior nuchal line to manubrium of sternum and medial 1/3rd of clavicle
- F: Unilaterally-rotating head to left and right; Bilaterally-flexes neck
- I: accesory nerve (CN XI)
- Clinical relevance: unilateral contraction used to test integrity of SCM and accessory nerve (CN XI)
Suprahyoid mm
digastric (two bellies)
mylohyoid
geniohyoid
Digastric (two bellies)
- A: mandible and mastoid process of TB. Both bellies attach to intermediate tendon, which is tied down to the hyoid bone by a sling of fascia
- F: Depress mandible, open mouth, and elevate hyoid bone
- I: Posterior belly—facial nerve (CN VII) Anterior belly—trigeminal nerve (CN V)
Posterior belly of the digatric mm
innervation
facial nerve (CN VII)
Anterior belly of the digastric mm
innervation?
trigemical nerve (CN V)
Mylohyoid
- A: medial surface of mandible to hyoid bone
- F: elevates hyoid, floor of mouth, and tongue during swallowing and speaking
- I: trigeminal nerve (CN V)
Geniohyoid
- A: from genio (or bend) of mandible to hyoid bone
- F: elevate hyoid, shortens floor of mouth
- I: C1 via hypoglossal nerve (CN XII)
Infrahyoid muscles
- Omohyoid (S) (“omo” shoulder)
- Sternohyoid (S)
- Sternothyroid (D)
- Thyrohyoid (D)
(S) superficial
(D) deep
Sternothyroid (D)
- A: from manubrium of sternum to thyroid cartilage of larynx
- F: Depress hyoid and larynx
- I: Ansa cervicalis (cervical loop)
Thyrohyoid (D)
- voice production
- A: from thyroid cartilage of larynx to hyoid bone
- F: Depress hyoid bone and elevate larynx
- I: C1 via hypoglossal nerve (CN XII)
Prevertebral mm
- LOCATION: deep to prevertebral fascia and posterior to retropharyngeal space.
- anterior scalene
- middle scalene
- posterior scalene
- longus capitis
- longus colli
Anterior Scalene
- A: from transverse process of C3 – C6 to 1st rib
- F: flex neck, and elevates 1st rib
- I: Cervical spinal nerves C4 – C6
Middle Scalene
- A: from posterior tubercle of transverse process of C5 – C7 to 1st rib
- F: flex neck laterally, and elevates 1st rib
- I: Anterior rami of cervical spinal nerves
Posterior Scalene
- A: from posterior tubercle of transverse process of C5 – C7 to 2nd rib
- F: flex neck laterally, and elevates 2nd rib
- I: Anterior rami of spinal nerves C7 – C8
Longus capitis
- A: from basilar part of OB to anterior tubercles of C3 – C6 transverse processes
- F: Flexion of head
- I: anterior rami of spinal nerves C1 – C3
Longus colli
- A: from anterior tubercle of C1, bodies of C1 – C3, and transverse processes of C3 – C6 to bodies of C5 – T3, and transverse processes of C3 – C5
- F: flexion of the neck (bilateral) and slight rotation of neck to contralateral side (unilateral)
- I: Anterior rami of spinal nerves C2 – C6
Trapezius
- A: medial third of superior nuchal line, nuchal ligament, spinous processes of cervical, thoracic, lumbar and sacral spinous processes to lateral third of clavicle, and acromion and spine of scapula
- F: elevate retract, and rotate scapula superiorly
- I: accessory nerve (CN XI)
Splenius capitis
- A: from nuchal ligament and spinous processes of C7 – T6 to mastoid process of TB and lateral third of superior nuchal line
- F: extend H&N (bilaterally), rotate and flex the head to same side
- I: posterior rami of cervical spinal nerves
Splenius cervicis
- A: from nuchal ligament and spinous processes of C7 – T6 to transverse processes of C1 – C4
- F: extend H&N (bilaterally), rotate and flex the head to same side
- I: posterior rami of cervical spinal nerves
Semispinalis capitis
- A: from transverse processes of C4 – T12 to OB and spinous processes of cervical and thoracic vertebrae
- F: extend head and neck, and rotate them contralaterally
- I: posterior rami of spinal nerves
suboccipital mm
Rectus capitis posterior major
Rectus capitis posterior minor
Obliquus capitis inferior
Obliquus capitis superior
Suboccipital triangle
- Boundaries: Obliquus capitis inferior, obliquus capitis superior, and rectus capitis posterior major
- Contains: vertebral artery and suboccipital nerve
- Clinical relevance: The vertebral artery is accessed here in order to conduct angiography of the circle of Willis.
- All muscles in the suboccipital triangle are innervated by the suboccipital nerve (posterior ramus of C1)
mm associated to styloid process
stylohyoid
styloglossus
stylopharyngeus
extrinsic tongue mm
genioglossus
hyoglossus
styloglossus
Genioglossus
- A: from mental spine to dorsum of tongue
- F: protrudes and depresses tongue
- I: hypoglossal nerve (CN XII)
Hyoglossus
- A: from hyoid bone to inferolateral aspect of tongue
- F: retrudes and depresses tongue
- I: hypoglossal nerve (CN XII)
anterior cervial region (anterior triangles)
submental triangle
submandibular triangle
carotid triangle
muscular triangle
Submental triangle
- Area inferior to the chin
- Boundaries: between R & L anterior belly of digastric m. and body of hyoid
- Content: submental lymph nodes, small veins joining to form anterior jugular v.
Submandibular triangle
- Glandular area
- Boundaries: between anterior and posterior bellies of digastric and inferior border of mandible
- Content: submandibular gland, submandibular lymph nodes, hypoglossal nerve (CN XII), mylohyoid nerve, parts of facial artery and vein
Carotid triangle
- Vascular area
- Boundaries: between anterior border of SCM, superior belly of omohyoid, and posterior belly of digastric
- Content: common carotid artery, internal jugular vein, vagus nerve (CN X), external carotid artery, hypoglossal nerve (CN XII), branches cervical plexus, thyroid gland, larynx, and pharynx
Muscular triangle
- Boundaries: anterior border of SCM, superior belly of omohyoid, and median plane of neck
- Content: infrahyoid muscles, thyroid, and parathyroid glands
posterior cervical region (posterior triangles)
occipital triangle
omoclavicular (subclavian) triangle
Occipital triangle
- Content: part of external jugular vein, posterior branches of cervical plexus, accessory nerve (CN XI), brachial plexus, cervical lymph node
Omoclavicular (subclavian) triangle
Content: subclavian artery, subclavian vein, and suprascapular artery
