Triangles of Neck

Question 1

Cervical plexus

Answer 1

4 Cutaneous branches

• Transverse cervical n. (C2,3): skin over lateral & anterior part of neck
• Greater auricular n. (C2,3): skin over parotid region, ear, and mastoid process
• Lesser Occipital n. (C2): skin of neck & scalp posterior to ear
• Supraclavicular n. (C3,4): skin over clavicle & shoulder

Motor

• Phrenic n. C3,4,5 keeps diaphragm alive

Question 2

Describe the branches of 1st, 2nd, and 3rd parts of subclavian a. and their areas of distribution

Answer 2

Vit C & D

• 1st
  
  • Vertebral br. of Subclavian a.: spinal cord & brain
  • Internal Thoracic br.: chest wall & ant. ab. wall
  • Thyrocervical trunk: thyroid gland & neck structures
• 2nd
  
  • Costocervical br.: upper 2 intercostal spaces & deep structures of neck
• 3rd
  
  • Dorsal scapular br.

Question 3

4 layers of deep cervical fascia

Answer 3

1. Investing layer of deep cervical fascia
2. Preverterabl layer: Phrenic n. deep in this
3. Pretracheal
4. Carotid Sheath: Internal Carotid a,v & CN X

Question 4

Muscles of Submental Triangle Floor

Answer 4

Suprahyoid muscles

• Geniohyoid: C1
• Mylohyoid: CN V3
• Anterior belly of digastric: CN V3
• Posterior belly of digastric: CN VII
• Stylohyoid: CN VII

Infrahyoid muscles

• Sternothyroid: ansa cervicalis
• Sternohyoid: ansa cervicalis
• Omohyoid: ansa cervicalis
• Thyrohyoid: C1

Question 5

Digastric (aka sub-mandibular) muscle boudaries

Answer 5

• Superiorly: mandible
• Posteriorly: post. belly of digastric
• Anteriorly: ant. belly of digastric

Question 6

List the muscle in the floor of the submental triangle

Answer 6

• Superior: Ant. belly of digastric
• Inferior: Body of hyoid
• Anteriorly: Midline
• Floor: Mylohyoid muscle
  
  • If mandible fixed: Myelohyoid elevates hyoid
  • If Hyoid fixed: Myelohyoid depresses mandible

Question 7

S. Carotid Triangles muscle borders

Answer 7

• Posterior: P. Belly of Digastric
• Anterior: A. Belly of Omohyoid
• Anterior border of SCM

Question 8

I. Carotid Triangle muscle borders

Answer 8

• Superior: S. belly of Omohyoid
• Anterior: SCM

Question 9

External carotid a. branches

Answer 9

Some Aggressive Lovers Find Odd Positions More Stimulating

• Superficial temporal br.
• Ascending Pharyngeal\
• Lingual br.
• Facial br.
• Omohyoid br.
• Post. Auricular
• Maxillary br.
• Superior thyroid br.

Question 10

Tracheotomy vs. Cricothyrotomy

Answer 10

Trach

• Transverse incision made thru skin, midpoint b/w suprasternal notch & thyroid cartilage
• Platysma & Pretracheal fascia divided
• Strap muscles retracted
• Thyroid Isthmus divided or retracted
• Opening made b/w 1st & 2nd Trach rings OR thru 2nd & 4th Trach rings
• Trach tube inserted

Cricothyrotomy

• Large-bore need inserted into cricothyroid membrane & connected to O2 supply
• Done in extreme emergency, performed if prox. airway is obstructed, to temporarily oxygenate Pt.