Anatomy of recurrent laryngeal nerve

1. Anatomy of recurrent laryngeal nerve
(RLN)
DENT113
PBL 3.4
“ Complicated thyroidectomy “
Supervision : Prof.Hanaa Gazaerly
By Ebtisam Ali

2. RECURRENT LARYNGEAL NERVE
• The recurrent laryngeal nerve is a myelinated nerve . It is
a branch of the vagus nerve (cranial nerve X).
• It's supply the sixth pharyngeal arche .
• The Branches provide both sensory and motor fibers.

3. There are two
recurrent laryngeal
nerves right and left
in the human body
both arising from the
vagus nerve but they
follow slightly
different courses on
the left and right
side.

4. The right recurrent laryngeal nerve
• Originates from the descending right vagus nerve as
it passes intermediate to the right subclavian
vein anteriorly and the right subclavian
artery posteriorly.
• It curves posteriorly around the inferior margin of
the right subclavian artery.
• Then, it passes medially and ascends over the
posterolateral surface of the trachea into the groove
between esophagus and trachea.

6. The left recurrent laryngeal nerve
• Originates from the left vagus nerve as it passes
over the arch of the aorta inferior to the left superior
intercostal vein.
• It passes medially and posteriorly deep to
the ligamentum arteriosum before curving inferior to
the arch of the aorta.
• It then passes superiorly over the left main bronchus
to ascend in the groove between the left side of the
trachea and the anterior of the esophagus.

7. Initially these nerves, branches of the vagus, supply the
sixth pharyngeal arches. When the heart descends, they
hook around the sixth aortic arches and ascend again to
the larynx, which accounts for their recurrent course.

8. • On the right, when the distal part of the sixth aortic arch and the
fifth aortic arch disappear, the recurrent laryngeal nerve moves
up and hooks around the right subclavian artery.
• On the left the nerve does not move up, since the distal part of
the sixth aortic arch persists as the ductus arteriosus, which later
forms the ligamentum arteriosum.

9. • The left RLN is longer
than the right Because it
crosses under the arch of
the aorta at the
ligamentum arteriosum
• Considering the extra
length and the distance
the left recurrent
laryngeal nerve has to
travel, it is the common
nerve affected by
diseases / disorders /
trauma etc .

11. Functions of RLN
• It has motor control of all the intrinsic muscles of the
larynx, the thyroarytenoid, the posterior and lateral
cricoarytenoid, and arytenoid muscles depends
upon the recurrent laryngeal nerve
• It transmits sensory information from the mucous
membranes of the larynx from the lower surface of the
vocal fold, downwards.

12. References
• Sunderland S, Swaney WE. The intraneural topography of the
recurrent laryngeal nerve in man. Anat Rec. Nov 1952;114(3):411-
26
• Moore, Keith L (1992), Clinically Oriented Anatomy (3rd ed.)
• F. Charles Brunicardi; F. Brunicardi; Dana Andersen; E. Pollock
Raphael, Timothy Billiar, David Dunn, John Hunter, Jeffrey
Matthews, Raphael E. Pollock (September 11, 2009). Schwartz's
Principles of Surgery (9th ed.). McGraw Hill Professional. pp. 1346–
1347. ISBN 978-0-07-154769-7.
• Grey's Anatomy , Henry Gray ,40th Ed.
• Textbook of laryngology Edited by : Albert L. Merati,MD,Steven A .
Bielamowicz,MD ,FACS ( 2006 )