002 the superficial structures of the neck Flashcards
what structures are in the anterior compartment of the neck?
- digestive, upper respiratory tract, neurovasculature
what structures are in the posterior compartment of the neck?
- vertebral column and associated musculature
what is the deep cervical fascia?
- encloses all neck compartments
- beneath superficial cervical fascia and platysma
- runs from the clavicle up to the mandible
what are the 3 layers of deep cervical fascia?
- superficial/investigating/anterior
- middle/pretracheal
- deep/prevertebral/posterior
what is in the superficial/anterior/investing layer of deep cervical fascia?
- encloses trapezius, sternocleidomastoid and carotid sheath
- anteriorly merges with fascia around infrahyoid muscles
- superiorly to external occipital protuberance and superior nuchal line
- laterally to mastoid process and zygomatic arch
- inferiorly to spine of scapula, clavicle and sternum
what is in the middle/pretracheal layer?
- encloses infrahyoid muscles, thyroid gland, trachea and oesophagus
- superiorly at hyoid bone
- inferiorly upper thoracic cavity
- separated pharynx and pretracheal layer
what is in the deep/prevertebral layer of the deep cervical fascia?
- encloses the erector spinae, prevertebral muscles, vertebral columnand scalene muscles
- superiorly /posteriorly = circular line around base of skull, superior nuchal line/occipital protuberance
- anteriorly = bottom of occipital bone and carotid canal and transverse processes of vertebrae
- laterally = mastoid process
what is the clinical significance of the spaces between the deep cervical fascia layers?
- fluid lies between these layers and can easily be infected/spread
how many cervical spines are there?
7
what are the names of c1 and c2?
c1 = atlas
c2 = axis
what features do cervical spine have?
- bifurcated spinous process
- coronal superior/inferior articular facets
- transverse process/foramen
- vertebral canal
- body except for atlas
-uncinate process to join bodies - anterior and posterior processes
what are the 3 different spaces between the deep cervical fascia?
- pretracheal space = between the superficial/investing fascia layer and the pretrachial fascia layer
- retropharyngeal space = between buccopharyngeal fascia and prevertebral fascia
- fascial space = within prevertebral layer, this layer splits into 2 laminae to create fascial space from base of skull to diaphragm
what are the 3 scalene muscles and what do they do?
- anterior = elevation of rib 1 and lateral bending of neck
- middle = elevation of rib 1 and lateral bending of neck
- posterior = elevation of rib 2 and lateral bending of neck
what are the origins/insertions of the 3 scalene muscles?
- all deep to sternocleidomastoid and omohyoid
- anterior = transverse processes of C3-6 to upper surface of rib 1
- middle = transverse processes of C2-6 to upper surface of rib 1
- posterior = transverse processes of C4-6 to upper surface of rib 2
what are the scalene muscles innervated by?
- anterior rami of C3-7
what are the suprahyoid muscles and what do they do?
- stylohyoid, digastric, mylohyoid, geniohyoid
- pulls hyoid upwards and back
what are the attachments of the stylohyoid?
- from styloid process of temporal bone to lateral area of hyoid bone
what is the innervation and function of the stylohyoid?
- facial nerve
- pulls hyoid bone upwards and backwards
what are the attachments of the digastric muscles?
- anterior belly = digastric fossa lower inside of mandible to tendon between bellies
- posterior belly = tendon to mastoid process of temporal bone
what is the innervation and functions of the digastric muscles?
anterior = mylohyoid nerve (mandibular nerve branch), opens mouth by lowering mandible
posterior = fascial nerve
- when mandible fixed = raise hyoid
- when hyoid fixed = lower mandible and open mouth
what are the attachments of the mylohyoid
- mylohyoid line on mandible to hyoid bone
what is the innervation and action of mylohyoid?
mylohyoid nerve (mandibular nerve branch)
- supports elevation of mouth / hyoid
what are the attachments of geniohyoid?
- inferior mental spine on inner surface of mandible to anterior surface of hyoid
what is the innervation and action of geniohyoid?
- hypoglossal nerve (C1)
- fixed mandible = hyoid up and forward
- fixed hyoid = mandible down and inwards
what are the infrahyoid muscles?
- aka strap muscles
- sternohyoid, omohyoid, thyrohyoid, sternohyoid
what are the attachments of the sternohyoid?
- sternoclavicular joint to the hyoid bone
what is the innervation and action of the sternohyoid?
- ansa cervicalis (C1-3)
- depresses hyoid after swallowing