Xvi: Tracheostomy Anatomy


  • Superior: inferior end of larynx (cricoid cartilage and level of C6 vertebra)
  • Inferior: tracheal bifurcation at plane of Ludwig (level of sternal angle and T4 vertebrae)
  • Terminates by division into right & left mainstem bronchi


  • Runs at 15° parallel to surface of neck, such that distal trachea is deeper than proximal trachea (slants from anterior position beneath larynx to posterior position at carina)
  • Tracheal length 10-13cm
  • Tracheal width 1.5-2cm (wider in men than women)
  • D-shaped cross section
    • Anterior wall formed by 18-22 incomplete cartilaginous rings which maintain tracheal patency
      • C shaped cartilages (first cartilage is bigger than others in cervical trachea)
      • Joined vertically by fibro-elastic tissue
    • Posterior wall of trachea spanned by longitudinal smooth muscle known as trachealis
  • Divided into 2 parts
    • Cervical: begins at inferior border of larynx (cricoid cartilage) located at level of C6 → level of jugular notch of sternum (upper border of superior mediastinum)
    • Thoracic: begins from superior thoracic aperture → ends at tracheal bifurcation (level of sternal angle and T4/5)

Relationships (Cervical part)


  • Visceral cervical fascia
  • Isthmus of thyroid: crosses trachea between 2nd – 4th tracheal cartilages
    • Superior to isthmus: inferior thyroid arteries
    • Inferior to isthmus: pretracheal fascia, inferior thyroid veins, thymus
    • Pretracheal lymph nodes


  • Oesophagus
  • Vertebral column (C6-T1)


  • Vessels: anterior jugular veins, common carotid artery and branches, inferior thyroid arteries and branches, inferior laryngeal arteries
  • Thyroid: lobes of thyroid gland which extend inferiorly until the 6th tracheal cartilage
  • Nerves: recurrent laryngeal nerve located slightly posteriorly compared to the rest
  • Paratracheal cervical lymph nodes
  • Muscles: sternohyoid, sternothyroid muscles

Relationships (Thoracic part)


From superior → inferior

  • Inferior thyroid veins, manubrium of sternum and attachments of sternohyoid and sternothyroid muscles
  • Brachiocephalic trunk and left common carotid artery
  • Aortic arch, left brachiocephalic vein, cardiac plexus and paratracheal thoracic lymph nodes


  • Oesophagus
  • Vertebral column (T1-T4/5)

Lateral on right side

  • Right vagus nerve
  • Right brachiocephalic vein
  • Superior vena cava
  • Azygos vein

Lateral on left side

  • Aortic arch
  • Left recurrent laryngeal nerve
  • Left common carotid artery
  • Left subclavian artery

Blood Supply

  • Arterial
    • Proximal half: tracheal branches of inferior thyroid artery
    • Distal half & carina: superior and middle bronchial arteries
  • Venous: inferior thyroid venous plexus

Lymphatic Drainage

  • Pretracheal nodes
  • Paratracheal cervical and thoracic lymph nodes


  • Pulmonary plexus
  • Recurrent laryngeal nerves

Histological Layers

  • Mucosa: ciliated pseudostratified columnar epithelium
  • Submucosa: consists of connective tissue that contains mucus glands, smooth muscle, vessels, nerves and lymphatics
  • Musculo-cartilaginous layer: cartilaginous rings and intervening smooth muscle
  • Fibroelastic adventitia

Surface Anatomy

Midline neck structure

  • Laryngeal structures: hyoid (C3), thyroid cartilage, cricothyroid membrane, cricoid cartilage (C6)
  • Sternal notch
  • Thyroid lobes: lie lateral to trachea

Layers of Dissection

  • Skin
  • Subcutaneous fat
  • Superficial & deep pretracheal fascia
  • Tracheal wall: ideally between 1st & 2nd rings

Anatomical Variation

  • Variant thyroid pyramidal lobe may extend over cricothyroid membrane
  • High-riding innominate artery
  • Median anterior jugular vein

Author: Novia Tan