CERVICAL FASCIA:

Fascia means fibrous connective tissue which binds together with various structures of the body.
Cervical fascia are of two types-
1. Superficial fascia.
2. Deep fascia.

SUPERFICIAL CERVICAL FASCIA:

Superficial fascia is the subcutaneous layer present just below the skin. The superficial cervical fascia is typically a thin lamina covering the platysma muscle.

DEEP CERVICAL FASCIA:

The deep fascia around the neck is known as deep cervical fascia or fascia Colli as it forms a collar around the neck. It lies deep to platysma muscle & present around the muscles, vessels & organs of the cervical region.

MODIFICATIONS OF DEEP CERVICAL FASCIA:


  1. Investing layer.
  2. Pretracheal layer.
  3. Prevertebral layer.
  4. Carotid sheath.
  5. Buccopharyngeal fascia.
  6. Pharngobasilar fascia.

1. INVESTING LAYER:


ATTACHMENTS:

Superior:
  • External occipital protuberance.
  • Mastoid process.
  • External acoustic meatus.
  • Zygomatic arch.
  • Base of the mandible.

Inferior:
  • Spine of scapula.
  • Acromion process.
  • Clavicle.
  • Manubrium sterni.

Anterior: Hyoid bone.
Posterior:
  • Seventh cervical vertebra.
  • Ligamentum nuchae.

COMPONENTS OF INVESTING LAYER:

It follows the rule of 2 as:
It encloses:
  • 2 muscles: Trapezius & Sternocleidomastoid.
  • 2 glands: Parotid & Submandibular salivary gland.
  • 2 spaces: Suprasternal space & Supraclavicular space.
  • It forms 2 fascial slings for omohyoid and digastric which forms the roof of the anterior & posterior triangles.
  • It gives 2 lamina for Pretracheal & Prevertebral fascia.
  • It forms 2 thickenings parotidomassaeteric fascia & stylomandibular ligament.

SUPRACLAVICULAR SPACE:

It is formed by splitting of investing layer medial 3rd of clavicle & gets attached to the anterior & posterior border of the upper surface of clavicle.
Contents: Supraclavicular nerves, External jugular vein.

SUPRASTERNAL SPACE:

It is formed by splitting of investing layer at the upper border of the sternum which gets attached to the anterior & posterior border of the suprasternal notch. It is also known as space of burns.
Content: Inter-clavicular ligament, Sternal head of sternocleidomastoid muscle, Jugular venous arch, Loose areolar tissue.

CLINICAL ANATOMY:

Parotiditis (Mumps): It is the inflammation of the parotid gland which is very painful due to the presence of thick tough the parotido-masseteric fascia which covers the parotid gland.

2. PRETRACHEAL FASCIA:

It is one of the lamina of deep cervical fascia that arises deep to the sternocleidomastoid muscle. This fascia is important because it encloses and suspends the thyroid gland and forms its false capsule.

Attachments:

Superiorly:-
  • Hyoid bone.
  • Thyroid cartilage.
  • Cricoid Cartilage.

Inferiorly:
  • It encloses inferior thyroid veins and finally blends with the arch of the aorta and fibrous pericardium.

On Either side: It forms the front of the carotid sheath.

CLINICAL ANATOMY:

  •  The fascia forms the outer false capsule of the thyroid gland, hence thyroid swellings grows posteriorly & may compress the oesophagus causing dysphagia.
  • Thyroid gland moves with deglutition as the posterior aspect of the gland is attached to the cricoid cartilage by a thickening of pretracheal fascia known as ligament of berry or suspensory ligament of thyroid gland.
  • Pretracheal fascia provides a free slippery base for the movement of the trachea during swallowing

3. PREVERTEBRAL FASCIA:

It lies in front of cervical vertebrae & muscles in front of it and forms the floor of the posterior triangle of the neck.
In front of the vertebral column, fascia is prominent and split in two Anterior/Alar fascia (blends with buccopharyngeal fascia) and Posterior/Prevertebral (Attach to the anterior longitudinal ligament and T4 vertebra) layers.

Attachments:

Superior: Skull base.
Inferior: In front of vertebral column fascia is prominent and split in two Anterior/Alar fascia (blends with buccopharyngeal fascia) and Posterior/Prevertebral (Attach to the anterior longitudinal ligament and T4 vertebra) layers.
Laterally: lies deep to the trapezius and attach to the SCM fascia.
It extends up to axilla as axillary sheath enclosing the axillary vessels and nerves

CLINICAL ANATOMY:

  • It extends up to axilla as axillary sheath enclosing the axillary vessels and nerves. Due to the extension of prevertebral fascia infections of vertebrae- caries spine (tuberculosis of vertebrae) may lead to spread of pus to the axilla.
  • Prevertebral fascia forms the posterior wall of retropharyngeal space & Retropharyngeal abscess causes dysphagia.

4. CAROTID SHEATH:

It is a fascial sheath situated deep to sternocleidomastoid muscle on each of the front of the neck. It is the condensation of the fibroareolar tissue around the main vessels of the neck.

Formation:

Anterior wall- By pretracheal layer of deep cervical fascia.
Posterior wall- By prevertebral layer of deep cervical fascia

CONTENT:

  •  Internal jugular vein laterally.
  • Common carotid artery ( in the lower part) & internal carotid artery ( in the upper part) medially.
  • Vagus nerve in between them.

Relations:

Anteriorly- ansa cervicalis.
Posteriorly – sympathetic trunk.

5. BUCCOPHARYNGEAL FASCIA:

It covers the superior constrictor muscle externally and forms the anterior border of the retropharyngeal space.

RETROPHARYNGEAL SPACE:

  • Posterior to pharynx and esophagus.
  • Anterior to alar layer of prevertebral fascia.
  • Extends from skull base to T1- T2

DANGER SPACE:

  • Anterior border- alar fascia.
  • Posterior border- prevertebral layer.
  • Extends from skull base to diaphragm and is so named because it contains loose areolar tissue and offers little resistance to the spread of infection.

PREVERTEBRAL SPACE:

  • Anteriorly by prevertebral fascia.
  • Posteriorly by is vertebral bodies.
  • Extends along the entire length of the vertebral column.


6. PHARYNGOBASILAR FASCIA:

It lies deep to the pharyngeal muscle and is thickened between the upper border of superior constrictor muscle and the base of the skull.