Gross 2 Head and Neck Lect. Flashcards
Describe the Hyoid. (Osteology, and what does it help with)
Consist of 3 part: Body, Greater & Lesser horn
- This bone does not articulate with any other bone
- Helps maintain the airway open
What are the 3 unpaired Laryngeal Cartilages?
- Thyroid Cartilage: Largest of all cartilages, lies at level of C4-C5
- Cricoid Cartilage: Smaller than thyroid cartilage but is thicker and stronger, shaped like signet ring. Lies at level of C6
- Epiglottis: Attached by ligament to the posterior aspect of the thyroid cartilage
What are the 3 paired Cartilages?
- Arytenoids: Are 3-sided pyramid cartilages that articulate with the lateral parts of superior border of the Cricoid cartilage lamina
- Corniculates: Attach to apices (top) of arytenoid cartilage
- Cuneiforms: Do no directly attach to other cartilage
(The Corniculates and Cuneiform cartilages appear as small nodules in the posterior parts of the aryepiglottic folds)
Where is the Superficial Facia located in the neck?
Its a fatter layer located between the dermis and investing facia
What contents are found in the Superficial Facia?
The Platysma muscle, which is found in the anterior lateral aspect
What is the Platysma?
A sheet of muscle in the subcutaneous tissue
- The fibers of this muscle diverge which leaves a gap anterior to larynx and trachea
- This is a muscle considered of facial expressions
- Tenses skin of neck
- Draws corners of mouth inferiorly and laterally
- Also assist with mandibular depression
What contents are found in the Deep Fascia of the neck?
- Investing Layer
- Pretracheal Layer
–Muscular layer
–Visceral layer - Carotid Sheath
- Prevertebral Layer
This is from superficial to deep
What muscles are found in the Investing Layer?
- Sternocleidomastoid (SCM)
- Trapezius
What are the contents of the Pretracheal Layer? (Muscular and Visceral)
Muscular:
- Sternohyoid
- Sternothyroid
- Thyrohyoid
- Omohyoid
Visceral:
- Thyroid Glands
- Trachea
- Esophagus
What contents are in the Carotid Sheath?
- Carotid Artery
- Internal Jugular Vein
- Vagus Nerve
What are the muscles of the Prevertebral Layer?
(Anterior and Lateral)
Anterior:
- Rectus Capitis Anterior
- Anterior Scalene
- Longus Coli
- Longus Capitis
Lateral:
- Rectus Capitis Lateralis
- Middle Scalene
- Posterior Scalene
- Levator Scapulae
- Splenius Capitis
What is the relationship between the Scalene muscles, the brachial plexus, and the subclavian vessels?
- Roots of the brachial plexus course between Anterior and Middle Scalene
- The Subclavian Artery courses between the Anterior and Middle Scalene
- The Subclavian Vein courses anteriorly to the Anterior Scalene
This is known as Scalene Triangle
What does the Internal Jugular Vein drain blood from? And where does the Internal Jugular drain into?
- Brain
- Anterior Face
- Cervical Viscera
- Deep muscles of the neck
The internal jugular then drains into Subclavian Vein
What innervations does the Vagus Nerve supply?
- Major Parasympathetic nerve
- Pharyngeal, Laryngeal and Cardiac Branches
What are the Motor Nerves of the Neck, what are their nerve roots and what do they innervate? (2)
These are the Motor Nerves for Cervical Plexus
Ansa Cervicalis:
(Superior root- C1-C2)
(Inferior root- C2-C3)
Motor nerve for Infrahyoid Muscles
{Sternohyoid, Sternothyroid, Omohyoid, Thyrohyoid}
Phrenic:
(C3-C5)
Motor for the Diaphragm
What are the Sensory Nerves of the Neck, what are their nerve roots and what do they provide sensory for? (4)
These are the Sensory Nerves for Cervical Plexus
- Lesser Occipital: (C2) Posterior neck and scalp, superior to auricle
- Great Auricular: (C2-C3) Skin around angle of Mandible to Mastoid process, some posterolateral ear
- Transverse Cervical: (C2-C3) Anterior cervical region.
- Supraclavicular: (C3-C4) Skin of neck that cross the clavicle and supply the skin over the shoulder
