Important structures in the neck

Vascular

• Carotid and vertebral arteries carry high volumes of blood to meet requirements of the brain. Returns through jugular veins.
• carotid body in close proximity to the carotid bifurcation. composed chemoreceptor cell, detects changes blood composition in the common carotid as it forms the internal and external carotid arteries.

Nerve plexi cervical and brachial

• Vagus nerve in the neck
  • Pharyngeal branches: motor innervation of the pharyngeal and soft palate muscles
  • Superior laryngeal nerve: splits into two branches
    • Internal laryngeal nerve: sensory innervation of the laryngopharynx and larynx above the vocal cords
    • External laryngeal nerve: motor innervation of the cricothyroid muscle
  • Right recurrent laryngeal nerve: passes under the right subclavian artery
  • Left recurrent laryngeal nerve: passes under the aortic arch
• phrenic nerve: bilateral, mixed nerve originating from the cervical nerves in the neck and descends through the thorax to innervate the diaphragm. Only source of motor innervation to the diaphragm

cervical lymph nodes clinically important because it can reveal signs of infection of the head and neck.

organs:

• larynx from the respiratory system
• the upper oesophagus from the gastrointestinal system
• thyroid and parathyroid glands which are part of the endocrine system
• Retropharyngeal space: runs from the base of the skull to the mediastinum, bound by the carotid sheath laterally, the prevertebral muscles posteriorly, and the esophagus anteriorly. Susceptible to deep neck infections (e.g., retropharyngeal abscesses)

Thyroid surgery complications

• Transient/permanent postoperative hypoparathyroidism (most common)
• Transient/permanent RLN palsy: Injury to the recurrent laryngeal nerve → potential unilateral vocal cord paralysis. new-onset hoarseness, changes in vocal pitch, or noisy breathing.
• Superior laryngeal nerve palsy: external superior laryngeal nerve damage → paralysis of the cricothyroid muscle, which functions to lengthen, stiffen, and thin the true vocal cord. Voice changes resulting from damage to this nerve may include hoarseness, voice fatigue, poor vocal volume and projection, and decreased vocal register.