Overview
Providing a support network
to the structures of the neck, the deep cervical fascia has 4 components – a
superficial (investing) layer, a middle (pretracheal) layer, a deep
(prevertebral) layer and the carotid sheath which is continuous at various
points with the aforementioned fascial layers.
Gross Anatomy
Investing layer; forms a collar encompassing whole neck
Superiorly attaches along the inferior edge of the mandible,
mastoid process, superior nuchal line & external occipital protuberance
Inferiorly spine & acromion of scapula, clavicle and
manubrium
Posteriorly blends with the nuchal ligament
Anteriorly attaches to the hyoid bone
Splits around (and thus
contains) sternocleidomastoid and trapezius muscles
Encompasses submandibular and
parotid glands
Forms a fibrous sling to
anchor the intermediate tendon of omohyoid close to clavicle
Pretracheal layer; runs in the anterior neck from hyoid bone
into the thorax where it fuses with the fibrous pericardium.
Divided into two parts
Visceral
layer encompasses thyroid gland,
parathyroid gland, trachea & oesophagus
(N.B. - posteriorly, it is
contributed to by the buccopharyngeal fascia)
Muscular
layer encompasses the infrahyoid
muscles
Prevertebral layer; fixed superiorly to the base of the skull, it
descends into the posterior mediastinum and continues as the endothoracic
fascia.
Surrounds paraspinal muscles
& cervical vertebrae
Carotid sheath; extends from the root of the neck to the base
of the skull. Antero-laterally it blends with the investing layer,
antero-medially with the pretracheal layer and posteriorly with the
prevertebral layer.
Contains the common carotid
artery, internal jugular vein, deep cervical lymph modes and vagus nerve.
Clinical Anatomy
Anterior to the prevertebral fascia and posterior to the alar
fascia, lies a potential space that runs unimpeded from the base of the skull
to the diaphragm that is known as the Danger Area. This is because it forms a
direct passage for the potential of infection into the thorax.
Not to be confused with the
retropharyngeal space which lies anterior to the alar fascia, posterior to
the pretracheal fascia. An abscess here can bulge into the pharynx, causing
dysphagia or dysarthria
Quick Anatomy
Key Facts
|
Quick-look
box – Deep Cervical Fascia |
|
|
Investing
layer |
· Sternocleidomastoid and trapezius · Submandibular and parotid glands |
|
Pretracheal
layer |
· Cervical viscera · Infrahyoid muscles |
|
Prevertebral
layer |
· Cervical vertebrae · Paraspinal muscles |
Aide-Memoire
Summary
The layers of the deep
cervical fascia act to support the cervical viscera, vessels and muscles, as
well as limit the spread of infection through the neck. They also allow for
structures to slide & move over one another (e.g. – swallowing, turning of
the head).
References
· Ellis H & Mahadevan V. 2010. Clinical Anatomy 12th ed.
Oxford: Wiley-Blackwell
· Whitaker RH & Borley NR. 2010. Instant Anatomy 4th ed.
Oxford: Wiley-Blackwell
· Sinnatamby CS. 2006. Last’s Anatomy 11th ed.
China: Churchill Livingstone
· Moore KL & Dalley AF. 2006. Clinically Oriented Anatomy 5th
ed. Baltimore: Lippincott Williams & Wilkins