Unit I: Deep Structures of the Neck Flashcards
A dense, sheet-like layer of CONNECTIVE tissue
Fascia
This surrounds and supports BOTH the superficial and deep structures of the neck.
-It consists of TWO major layers (superficial and deep)
Cervical fascia
The two major LAYERS of the Cervical fascia
1) Superficial cervical fascia
2) Deep cervical fascia
A thin layer of CONNECTIVE tissue deep to the skin that encloses the:
- Platysma muscle
- contains cutaneous nerves
- contains superficial veins and lymph nodes
Superficial cervical fascia
Four layers of the Deep cervical fascia
1) Investing layer
2) Pretracheal fascia
3) Prevertebral fascia
4) Carotid sheath
Most superficial layer of the deep cervical fascia that lies deep to the superficial cervical fascia and splits to enclose the SCM and and trapezius
Investing layer of Deep cervical fascia
This layer of deep cervical fascia encloses the thyroid gland, trachea, and esophagus. It begins above as Buccopharyngeal fascia. Found in the Muscular triangle
Pretracheal fascia
This layer of the deep cervical fascia encloses the vertebral column and the deep muscles of the back. Contains the sympathetic trunk on the anterior surface.
Prevertebral fascia
This layer of deep cervical fascia is a cylinder of fascia that extends from the base of the skull to the root of the neck. It contains many important structures
Carotid Sheath
The contents of the Carotid sheath
1) Common Carotid artery
2) Internal Carotid artery
3) Internal Jugular vein
4) Vagus nerve
5) Deep cervical lymph nodes
This nerve is located below the internal jugular vein and the internal Carotid artery
Vagus nerve
This artery splits into two branches: the internal Carotid artery and the external carotid artery in the carotid triangle
Common carotid artery
These drain all the lymph from the head and neck
Deep cervical lymph nodes
This artery exits the Carotid sheath BEFORE giving off its branches in the neck
External Carotid artery
Functions of the Fascial layers
1) Provides a slippery surface to REDUCE friction during gross movements of head and neck and during swallowing
2) Adhesions can cause neck pain
The most common place for adhesions in the neck
Between the investing layer of the deep cervical fascia and the superficial cervical layer
Clinical significance of Fascial layers
1) May serve as a channel for INFECTION
- -Pretracheal fascia may allow an infection to spread from head and neck to mediastinum directly (fascia surrounding heart)
2) Cancer involving cervical lymph nodes can compress INTERNAL JUGULAR VEIN, which would INCREASE cranial pressure.
This is an opening through which structures of the neck pass INTO the THORAX.
Superior Thoracic Aperture (Thoracic Inlet)
Boundaries of the Superior thoracic aperture (thoracic inlet)
1) first thoracic vertebrae
2) First ribs and their cartilages
3) Manubrium of sternum
This structure is kidney-shaped
Superior thoracic aperture (thoracic inlet)
Major structures passing through the Superior thoracic aperture
1) Arteries
- Brachiocephalic trunk
- Left common carotid artery
- left subclavian artery
- Internal thoracic artery
2) Veins
- Brachiocephalic vein
3) Nerves
- Phrenic nerve
- Vagus nerve
- Recurrent pharyngeal nerve
- Sympathetic trunk
4) Viscera
- Trachea
- Esophagus
- Cervical pleura
- Apex of lung
- Thymus
This artery passes through the Superior thoracic aperture behind the brachiocephallic vein. It exits into the right subclavian and right carotid arteries
Brachiocephallic trunk
This nerve supplies the diaphragm
Phrenic nerve
This is the most important nerve of the larynx
Recurrent Laryngeal nerve
This visceral membrane of the thorax covers the apex of the lung
Cervical pleura
Why is there a potential for lung collapse and with neck injury?
The cervical pleura and apex of the lung pass through the superior thoracic aperture immediately POSTERIOR to the origin of the SCM. A broken 1st rib or penetrating wound of the neck may cause the lung to collapse
Name for when the lung collapses
Atelectasis
This structure is part of the immune system and produces T-lymphocytes. It is usually composed of two irregular lobes and lies primarily BEHIND the manubrium and body of sternum
Thymus
This structure can extend into the neck and around the front and sides of the trachea
Thymus
Lies INFERIOR to the thyroid gland
Thymus
The sternohyoid and sternothyroid muscles lie ANTERIOR to the_____ and thyroid gland
Thymus
Blood supply to the Thymus
Internal thoracic artery
Nerve supply to the Thymus
Stellate ganglion of the sympathetic trunk and vagus nerve
This is an endocrine organ that produces thyroxine and calcitonin.
Thyroid gland
This endocrine organ lies at the level of C5 to T1
Thyroid gland
The thyroid gland is U or H shaped and consists of three parts
1) Left lobe
2) Right lobe
3) Isthmus