• The Larynx is an apparatus made up of cartilage, ligaments, muscles, and mucous membrane.
  • Guards the entrance to the lower respiratory passages  (trachea, bronchi, and lungs) and houses the vocal cords.
  • Occur during the 4th week of intra uterine life.
  • The respiratory primordium appears in the floor of the foregut in the 4th  week of gestational life.
  • The larynx begins as a slit like diverticulum (laryngotracheal groove ) in the ventral wall of the  primitive pharynx .
  • The groove gradually deepens and its edges fuse to form a septum,which separates the laryngotracheal tube from the pharynx and oesophagus.
  • The process of this fusion starts caudally and extend cranially
  • Between 5th & 6th weeks, — 3  swellings appear at the laryngeal aditus.
  • An anterior swelling , a derivative of the hypobranchial eminence from 4th arch—forms Epiglottis.
  • 2 lateral arytenoid swellings appear, derived from the 6th  branchial arch, move medially and form a T-shaped aperture
  • Laryngeal  lumen— temporarily occluded  at 8 weeks gestational age as a result of  epithelial proliferation.
  • By the 10th week of gestation, recanalization occurs and consequently pair of  laryngeal ventricles are formed. 
  • The laryngeal ventricles are bound by  mesenchyme tissue that  condense and progress into false and true vocal cords.
  • Laryngeal  cartilages develop from the mesenchyme of the branchial arches.
  • Thyroid  cartilage— from the 4th  arch mesenchyme  as two lateral plates meet in the midline.
  • Arytenoids , Corniculate , Cricoid & Tracheal cartilages–  6th  branchial  arch
  • Epiglottis —  develops  from Hypobranchial eminence
  • Intrinsic  laryngeal muscles develop from the mesoderm of the 4th and 6th  arches
  • Larynx is located anterior to the 3rd, 4th, 5th, and 6th cervical vertebrae.
  • Extends from the base of the tongue to the proximal portion of the trachea.
  • Laryngeal  skeleton is suspended from the hyoid bone by the medial and  lateral thyrohyoid membrane.
  • The 3rd to 6th cervical vertebrae, prevertebral muscles, and fascia lie posterior to the larynx.
  • Laryngofissure is opening of larynx in midline.

The cavity of the larynx extends:

  • Above  – from  the area of the tip of the  epiglottis, aryepiglottic folds,  and interarytenoid folds
  • Below  —  to  the 1st  tracheal ring

Internal  cavity of the larynx

Divided into 3  spaces:

  1. Supraglottic 
  2. Glottic
  3. Subglottic spaces


  • Size-  smaller in infants
  • Shape–  funnel shaped in infants , cylindrical in  adults
  • Softness– laryngeal cartilages are softer in infants
  • Superiorly placed  in infants helps child to breathe  & suckle at same time
  • Straighter and less oblique than in adults
  • Sensitivity is greater in infants more prone to spasm
  • Sub glottis is very narrow ,even a small swelling can lead to airway obstruction in infants
  • The narrowest part of the infantile larynx is the junction of subglottic larynx with trachea and this is because cricoid cartilage is very small
  1. Cartilages
  2. Joints
  3. Ligaments
  4. Membranes
  5. Muscles
  6. Mucous membrane
  7. Hyoid Bone
Exam Question
  • Superiorly placed larynx  in infants helps child to breathe & suckle at same time.
  • Larynx is funnel shaped in infant
  • Larynx is cylindrical shaped in adults
  • Cricoid Cartilage is the narrowest part of infantile larynx.
  • Laryngofissure is opening of larynx in midline.
Don’t Forget to Solve all the previous Year Question asked on Larynx

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