Cervical Plexus And Flashcards
What is the consequence of severance of the phrenic nerve?
Paralysis of the diaphragm
Temporary paralysis can also result from phrenic nerve block
What is a cervical plexus block used for?
Regional anaesthesia for neck surgery
Examples include carotid endarterectomy, thyroidectomy, and cervical lymph node excision
Which spinal nerves contribute to the phrenic nerve?
C3, C4, and C5
Where does the phrenic nerve lie in relation to the scalenus anterior muscle?
On the anterior surface of the scalenus anterior muscle
What are the four muscular branches of the ansa cervicalis?
- Superior belly of the omohyoid muscle
- Inferior belly of the omohyoid muscle
- Sternohyoid
- Sternothyroid
What is the function of the infrahyoid muscles?
Anchor the hyoid, sternum, clavicle, and scapula; depress the hyoid and larynx during swallowing and speaking
Which muscle is the only motor nerve to the diaphragm?
Phrenic nerve
What are the two layers of the infrahyoid muscles?
- Superficial layer: Sternohyoid, Omohyoid
- Deep layer: Sternothyroid, Thyrohyoid
Fill in the blank: The _______ muscles are superior to the hyoid and connect it to the cranium.
suprahyoid
What is the origin of the digastric muscle’s anterior belly?
Digastric fossa of mandible
What action does the stylohyoid muscle perform?
Raises the hyoid bone upwards
Which nerve supplies the mylohyoid muscle?
Nerve to mylohyoid, a branch of the mandibular nerve
What can result from trauma to the ansa cervicalis?
Paresis or paralysis of the infrahyoid muscles, leading to swallowing difficulties
What is the nerve supply of the thyrohyoid muscle?
Fibres from C1 through hypoglossal nerve
True or False: All infrahyoid muscles are supplied by ansa cervicalis.
False
What is the primary action of the mylohyoid muscle?
Elevates hyoid, floor of mouth, and tongue during swallowing and speaking
What are the branches of the cervical plexus that provide cutaneous innervation?
- Lesser Occipital Nerve (C2)
- Greater Auricular Nerve (C2 & C3)
- Transverse Cutaneous Nerve (C2 & C3)
- Supraclavicular Nerve (C3 & C4)
What are the two series of deep branches of the cervical plexus?
- Medial series
- Lateral series
Which muscle aids in the lateral pterygoid’s function?
Digastric muscle
What is the significance of the cervical plexus in terms of innervation?
Supplies skin and muscles of neck and thoraco-abdominal diaphragm
What is the role of the ansa cervicalis?
Innervates the infrahyoid muscles
