Cervical Plexus

Question 1

Cervical plexus

Answer 1

• Anterior primary rami of C1-4
• Deep to SCM, has cutaneous and muscular branches

Question 2

Muscular branches

Answer 2

o C1 innervates geniohyoid muscle
 Assists in expanding airway
o Also innervates thyrohyoid muscle which elevates larynx
- C1-3 form “goose neck”= ansa cervicalis
- 4 muscle branches, supplying muscles known as infrahyoids
o Assist in swallowing and speech
o Sternohyoid, sternothyroid, omohyoid (superior belly), omohyoid (inferior belly), and thyrohyoid

Question 3

C3-5

Answer 3

Phrenic
- Diaphragm
- C3-5, anterior scalenes, penetrates thoracic cavity, descends to base of lung, before reaching diaphragm

Question 4

C1-2

Answer 4

Rectus Capitis

Question 5

C1-3

Answer 5

Longus Capitis

Question 6

C2-3

Answer 6

SCM, traps

Question 7

Sensory branches

Answer 7

• Cutaneous supply serves skin of neck, scalp, ear, upper thorax
• Comprises
  o Great auricular
  o Lesser occipital
  o Transverse cervical
  o Supraclavicular

Question 8

Which point to sensory branches penetrate

Answer 8

Erbs point
o Posterior to medial aspect of SCM
o Commonly used for plexus nerve blocks in preparation for head or neck surgery

Question 9

Greater auricular

Answer 9

• Largest ascending branch of plexus
• C2-3
• Sensory supply to outer ear and skin of jaw angle

Question 10

Lesser occipital

Answer 10

• C2
• Supplies sensation to superior posterior scalp

Question 11

Transverse cervical

Answer 11

• C2-3
• Traverse SCM
• Sensation for ant neck and sternum

Question 12

Supraclavicular

Answer 12

• C3-4
• Sensation to skin overlying supraclavicular fossa and SC Jt