FRONT OF THE NECK AND ANTERIOR TRIANGLE

FRONT OF THE NECK AND ANTERIOR TRIANGLE

Subdivisions of Anterior Triangle:

1. Carotid triangle
2. Digastric triangle
3. Submandibular triangle
4. Digastric triangle (also known as submandibular triangle)

Boundaries and Contents of Carotid Triangle:

1. Boundaries
   • Anteriorly: Lower border of the mandible
   • Posteriorly: Posterior belly of digastric muscle
   • Superiorly: Lower border of the posterior belly of the digastric muscle
2. Contents
   • Carotid artery
   • Deep cervical lymph nodes
   • Internal jugular vein

Boundaries and Contents of Digastric Triangle:

1. Boundaries
   • Anteriorly: Posterior belly of the digastric muscle
   • Posteriorly: Anterior belly of the digastric muscle
   • Superiorly: Lower border of the mandible
2. Contents
   • Submandibular gland
   • Submandibular lymph nodes
   • Facial vein
   • Hypoglossal nerve

Principal Neurovascular Bundle of the Neck: The principal neurovascular bundle of the neck consists of

• Common carotid artery
• Internal jugular vein
• Vagus nerve

Applied Anatomy:

1. The anterior triangle of the neck is a region of clinical importance due to the presence of vital structures.
2. The carotid triangle is of clinical significance due to the presence of the common carotid artery, which can be palpated during clinical examination.
3. The digastric triangle is important due to the presence of the submandibular gland, which can be palpated during clinical examination.
4. The principal neurovascular bundle of the neck is of clinical significance due to the risk of damage during surgical procedures.

Muscle Action Sequence:

1. The posterior belly of the digastric muscle is innervated by the facial nerve.
2. The anterior belly of the digastric muscle is innervated by the mylohyoid nerve.
3. The digastric muscle is involved in the depression of the mandible.

Stepwise Anatomical Mechanism: 1 → 2 → 3

1. The posterior belly of the digastric muscle is activated.
2. The anterior belly of the digastric muscle is activated.
3. The mandible is depressed.