The document discusses the anatomy of the larynx. It describes the cartilages that make up the larynx, including the thyroid, cricoid, epiglottis, and others. It discusses the joints and membranes in the larynx. It also summarizes the intrinsic and extrinsic muscles that control the larynx, as well as the blood supply, nerve supply, and embryonic development of the larynx.

1. Dr Ajeet Kumar Khilnani
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2.  Also called ‘voice box’
 Lies in front of hypopharynx
 Opposite the C3-C6 vertebrae
 It moves vertically and in AP direction during
swallowing and phonation
 Laryngeal crepitus: Passive movement of
larynx from side to side producing a grating
sensation
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3.  Larynx has 3 unpaired & 3 paired cartilages
 Unpaired
- Thyroid
- Cricoid
- Epilottis
 Paired
- Arytenoid
- Corniculate
- Cuneiform
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4. Thyroid cartilage (Hyaline)
 Largest of all
 Two alae meet anteriorly to form an angle of
90º in in males and 120º in females
 Vocal cords are attached to the middle of
thyroid angle
 Most of the FBs are arrested above the vocal
cords, hence cricothyrotomy secures airway
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5. Cricoid cartilage (Hyaline)
 Only cartilage forming a complete ring
 Anterior narrow part is arch
 Posterior expanded part is lamina
Epiglottis (Fibroelastic)
 Leaf like, yellow, elastic cartilage
 Fat in the anterior surface (pre epiglottic
space). This space can be invaded by
supraglottic CA or CA BOT
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6. Arytenoid cartilages (mostly hyaline)
 Pyramidal in shape
 Base: articulates with cricoid cartilage
 Lateral muscular process: For intrinsic
muscles of larynx
 Anterior vocal process: For vocal cord
 Apex: Supports the corniculate cartilage
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7. Corniculate cartilages (of Santorini)
 Fibroelastic
 Each articulates with apex of arytenoid
cartilage
Cuneiform cartilages (of Wrisberg)
 Fibroelastic
 Rod shaped
 Situated in aryepiglottic fold
 Provide passive support to the fold
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9.  Criciarytenoid joint
- Synovial
- Rotatory movement (adduction & abduction
of VC)
- Gliding movement (closing & opening the
posterior part of glottis)
 Cricithyroid joint
- Synovial
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10.  Extrinsic membranes
- Thyrohyoid membrane: Pierced by superior
laryngeal vessels & internal laryngeal nerve
- Cricothyroid membrane
- Cricotracheal membrane
 Intrinsic membranes
- Cricovocal membrane: Its upper free border
forms vocal ligament (true vocal cord). It forms
conus elasticus (subglottic FBs lodge here)
- Quadrangular membrane: Its lower border
forms vestibular ligament (false vocal cord)
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11.  Intrinsic Muscles (b/w laryngeal cartilages)
(a) Those acting on VC
- Abductors: Posterior criciarytenoid
- Adductors: Lateral cricoarytenoid
Interarytenoid (transverse)
Thyroarytenoid (external part)
- Tensors: Cricothyroid
Vocalis (internal part of
thyroarytenoid)
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12. (b) Those acting on laryngeal inlet
- Openers of inlet
Thyroepiglottic (part of thyroarytenoid)
- Closers of inlet
Interarytenoid (oblique part)
Aryepiglottic
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14.  Extrinsic Muscles (b/w larynx & neighbours)
- Elevators: Primary and Secondary
Primary elevators (attached to thyroid):
Stylopharyngeus, Salpingopharyngeus,
palatopharyngeus & thyrohyoid
Secondary elevators (attached to hyoid):
Mylohyoid, Digastric, Stylohyoid & Geniohyoid
- Depressors: Sternohyoid, Sternothyroid &
Omohyoid
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16.  From laryngeal inlet to lower border of cricoid
cartilage
 3 parts: Vestibule, Ventricle & Subglottic
space
- Vestibule: From laryngeal inlet to vestibular
folds
- Ventricle (sinus of larynx): B/w vestibular and
vocal folds. Saccule is a diverticulum of
mucus membrane (Laryngocele)
- Subglottic space: From VC to lower border of
cricoid cartilage
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18.  Vestibular folds (false VC)
- Contain vestibular ligament
 Vocal folds (true VC)
- Contain vocal ligament
 Glottis (rima glottidis)
- AP length 24 mm in men, 16 mm in women
- Narrowest part of larygneal cavity
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20.  Supraglottic: Pierce the throhyoid membrane
& drain into upper deep cervical
 Infraglottic: Pierce the cricothyroid membrane
& drain into prelaryngeal & pretracheal nodes
 Glottic: No lymphatics
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21.  Motor: RLN (except cricothyroid, which is
supplied by external laryngeal nerve, branch
of SLN)
 Sensory
- Above VC: Internal laryngeal nerve (SLN)
- Below VC: RLN
 RLN arises from vagus. Left RLN has a longer
course (it arises in mediastinum), so more
prone to paralysis
 SLN arises from inferior ganglion
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23.  Pre-epiglottic space of Boyer
- Filled with fat
- Continuous laterally with paraglottic space
 Paraglottic space
- Growths which invade this space can
present in the neck through cricothyroid
space
 Reinke’s space
- Under the epithelium of VC
- Reinke’s edema: fusiform swelling of
membranous cords
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24.  Epiglottis: Hypobranchial eminence
 Upper part of thyroid cartilage: 4th Arch (SLN)
 Lower part of thyroid cartilage
 Cricoid/Corniculate/Cuneiform 6th Arch
 Intrinsic muscles of larynx (RLN)
 Upper part of body & lesser cornu
of hyoid 2nd Arch
 Stylohyoid ligament
 Lower part of body and greater cornu of
hyoid: 3rd Arch
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25.  Positioned high at C3 or C4 at rest and
reaches C1 or C2 during swallowing
 Laryngeal cartilages are soft & collapse easily
 Epiglottis in omega shaped
 Thyroid cartilage is flat
 Larynx is small & conical (subglottis is
narrowest)
 Submucosal tissues are loose
 VC is 6 mm in females, 8 mm in males
(children), 15-19 mm in females & 17-23
mm in males (adults)
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