Dr.A.GANESH BALA M.S ENT ASSOCIATE PROFESSOR VMMC - KARAIKAL

1. Dr.A.GANESH BALA M.S ENT
ASSOCIATE PROFESSOR
VMMC - KARAIKAL

2. 1. EMBRYOLOGYOF PHARYNX
1. PHARYNGEALGUT
2. PHARYNGEALARCHES
3. PHARYNGEALPOUCHES
4. PHARYNGEALCLEFTS

3. 1. ANATOMYOF PHARYNX
1. GENERALDESCRIPTIONS
2. NASOPHARYNX( POST-NASALSPACE)
3. OROPHARYNX
4. HYPOPHARYNX ( LARYNGOPHARYNX)
5. STRUCTUREENTERINGTHEPHARYNX
6. NERVESUPPLYOF PHARYNX
7. BLOOD SUPPLYOF PHARYNX
8. LYMPHATICSOF PHARYNX

4. 1. SOFTPALATE
1. STRUCTURE
2. MUSCLES
a. Tensor palati ,
b. Levator palati ,
c. Palatoglossus,
d. Palatopharyngeus ,
e. Uvularmuscles
4. NERVESUPPLY
5. BLOODSUPPLY
6. LYMPHATICS

5. 1. THE PHARYNGEALWALL
1. MUCOUS MEMBRANCE
2. PHARYNGOBASILARFASCIA
3. MUSCLELAYER
a. Sup.constrictor muscle
b. Inf.constrictor muscle
c. Stylopharyngeus
d. Palatopharyngeus
e. Salpingopharyngeus
4. BUCCOPHARYNGEALFASCIA

6. EMBRYOLOGY OF PHARYNX

8. Duringthe earlystageofembryonicdevelopment ,
cephalocaudal& lateralfoldingresults in formationof an
endodermallylined primitivegut.
In its cephalic partthisformsa blindending tube, the
foregut,whichis separatedbytheectodermallylined
stomatodaeumbythebucco-pharyngealmembrane.
This rupturesandthestomatodeumcontinueswiththe
foregut.
Theendodermallining ofthe foregutdifferentiatestoform
manypartsofthe aero-digestivetractincluding pharynx&
oesophagus.
Sagittal midline section of a 23 – 25 day embryo

9. First pharyngeal arch
Consists of 2portion –
dorsal portion ( Maxillary Process )
ventral portion ( Mandibular Process )
Mandibular process contains Meckle’s Cartilage and during
furtherdevelopment it disappers except for the 2 small portions
at its dorsal end to form the Incusand Malleus.
Mesenchymeof the maxillaryprocess gives rise to Premaxilla ,
Maxilla , Zygomatic Bone , and ThePart Of Temporal Bone. (
thro’ membranousossification)
Mandible is also formedby membranousossification of the
mesenchymal tissue surroudingMeckle’s cartilage.

10. Masculature of 1st pharyngeal arch:
Muscles of mastication (Temporalis , Massetor , Lateral
And Medial Pterygoids ),anterior belly of digastric , mylohyoid , tensor
tympani & tensor palatini.
Nervesupply : Mandibular Branch Of Trigeminal Nerve
Sincemesenchyme from the 1st arch also contributes to dermis of the face ,
sensory supply to the skin of face is provided by Ophthalmic , Maxillary , and
Mandibular Branches Of Trigeminal Nerve.

11. SECOND PHARYNGEAL ARCH
Thecartilage of the second orhyoid arch gives raise to the stapes ,styloid process
of the temporal bone , stylohyoid ligament and ventrally the lesserhorn andupper
part of the bodyof the hyoid bone.
Muscles of the hyoid arch arethe stapedius ,stylohyoid , posterior belly of the
digastric, auricular and muscles of the facial expression.
Thefacial nerve , the nerve of the second arch ,supplies all of these muscles.

12. Thirdpharyngeal arch
Thecartilage of the third pharyngeal arch produces the lower part of the
body and greater horn of the hyonid nbone.
Themusculatare is limited to the stylopharyngeus muscles.
These muscles are innervated by the glossopharyngal nerve,the nerveof
the third arch.

13. Fourth and SixthPharyngealArches
Cartilaginous components of the fourth and Sixth pharyngeal arches fuse to
form the thyroid, cricoid, artyenoid ,corniculate and cuneiform cartilages of larynx .
Muscles of the fourth arch (cricithyroid ,levator palatini and constrictors of
the pharynx ) are innervated by the superior laryngeal branch of the vagus, the nerveof
the fourth arch.
Intrisinic muscles of the larynx are supplied by the recurrentlaryngeal branch
ofthe vagus,the nerveofthe sixth arch.

14. Arch and nerve development
ARCH POST-TREMATIC NERVE PRE-TREMATIC NERVE
1st Mandibular nerve( V ) Chordatympani branch of VII
2nd Facial nerve( VII) Tympanicbranchof IX
( Jacobson nerve)
3rd Glossopharyngeal nerve( IX)
4th
5th
6th
Vagus ( X ) and Accessory ( XI ) nerves via
superior and recurrentlaryngeal and
pharyngealbranches
Pretrematic nervesnot well defined in
man

15. Pharyngeal pouches
The human embryo has5 pairs of pharyngeal pouches.
The last one of these is atypical and often considered as part of
the fourth.
Since the epithelial endodermal liningof the pouches gives rise to
a number of important organs ,the fate of each pouch is discussed
separately.

16. FIRST PHARYNGEAL POUCH
Thefirst pharyngeal pouch forms a stalk like diverticulum , the
tubotympanic recess, which comes in contact with the epithelial lining of the
first pharyngeal cleft, the future external auditory meatus .
Thedistal portion of the diverticulum widens into a saclike structure ,
the primitive tympanic (or) middle ear cavity , and the proximal part remains
narrow , forming the audiotory (eustachain) tube.
Thelining of the tympanic cavity aids in the formation of the tympanic
membranceoreardrum.

17. Second pharyngeal pouch
Theepithelial lining of the second pharyngeal pouch proliferates and
forms buds that penetrate into the surrounding mesenchyme .
Thebuds are secondarily invaded by mesodermal tissue forming the
primordium ofthe palatine tonsil .
During the third and fifth months ,the tonsil is infiltrated by lympatic
tissue.
Part of the pouch remains and is found in the adult as the tonsillar
fossa.

18. Third pharyngeal pouch
The thirdandfourthpouchesarecharacterizedattheir distalextremitybya dorsalandaventral
wing.
In thefifthweek , epithelium of thedorsalwing ofthe thirdpouchdifferentiatesintothe inferior
parathyroidgland,while theventral wing formsthethymus.
Bothglandprimordialose theirconnectionwiththe pharyngealwall ,andthethymusthenmigrates
in acaudalandamedial direction, pulling theinferiorparathyroidwith it.
In theanteriorpartofthe thoraxit fusesfromtheoppositeside,its tailportionsometimes persists
eitherembeddedin thethyroidgland orasisolatedthymic nests.
The parathyroidtissueof thethirdpouchfinallycomes torest onthe dorsalsurfaceofthe thyroid
glandandformsthe inferiorthyroidgland.

19. Fourth pharyngeal pouch
Epithelium of the dorsal wing of the fourth pharyngeal pouch forms the superior
parathyroid gland.
When the parathyroid gland loses contact with the wall of the pharynx , it
attaches itself to the dorsal surface of the caudally migrating thyroid gland as the
superior parathyroid gland.

20. Fifthpharyngeal pouch
Last to develop.
Is considered to bepartof 4th pouch.
Gives rise to ultimo-branchial body, which is later incorporated into
the thyroid gland.
Cells of the ultimobranchial body givesrise to parafollicular , orC
cells of the thyroid gland. ( which secrete calcitonin ,a hormone involved in
regulation of the calcium level in the blood).

21. Pharyngealclefts
The5 week embryo is characterised by presence of4 pharyngeal clefts , ofwhich one
contribute to the definitive structure of the embryo.
Thedorsal partofthe first cleft penetrates the underlying mesenchyme and gives rise
to the External Acoustic Meatus.
Theepithelial lining at the bottom of the meatus participates in the formation of the
eardrum.

22. Pharyngealclefts (contd…)
Activeproliferation of the mesenchymal tissue in the 2nd arch causes it to
overlap the 3rd and 4th arches.
Finally it merges with the epicardial ridgein the lower part of the neck.the 2nd ,3rd
,4th clefts lose contact with the outside.
Theclefts forms a cavity lined with ectodermal epithelium ,the cervical sinus ,
but with further development , the sinus disappear.

26. Boundaries
Superiorly: base of the skull including the posterior part ofthe sphenoid and the
basilar part of the occipital bone in front of the pharyngeal tubercle.
Inferiorly: the pharynx is continuous with the oesophagus at the level of the sixth
cervical vertebra corresponding to the lower borderof the cricoids cartilage.
Posteriorly: Thepharynx glides freely onthe prevertebral fascia which separates it
from the cervical spine.
Anteriorly: it communicates with the nasal cavity the oral cavity and larynx thus
the anterior wall of the pharynx is complete.

27. On the each side
(A)thepharynxis attached to
(a) the medial pterygoid
plate;(b)the pterygo-mandibular raphe;(c)the
mandible;(d)the tongue;(e)the hyoid bone;and
(f)the thyiod and cricoids cartilages.
(B)it communicates on each side with the middle
ear cavity through the auditory tube.
(C)the pharynxis related on either side to:
(a)the styloid process and the muscles
attached to it and
(b)the common carotid, internal
carotid and external carotid and thecranial nerves
realted to them.

29. NASOPHARYNX
Thenasopharynx is behind the posterior apertures (choanae)of the nasal
cavities , abovethe level of the hardpalate and lateral tothe top ofthe soft palate
.
Its ceiling is formedby the sloping base of the skull and consists of the posterior
partofthe body of the sphenoid bone andthe basal part of the occipital bone
(BASI-SPHENOID).
Theceiling and lateral walls of the nasopharynx form a domed vault at the top of
the pharyngeal cavity that is always open.

30. Roof : Basisphenoid & Basioccipital
POSTERIOR WALL : C1Vertebrae
ANTERIOR WALL : Choanae( Inferior& Middle )
PosteriorEdge Of NasalSeptum
LATERAL WALL : Pharyngealopening ofEustachiantube
FossaofRossenmuller
Torustubaralis
Floor : Softpalteantriorly
Nasopharyngealisthmusposteriorly

32. Elevation of the soft palate and constriction of the palatopharyngeal sphincter close the pharyngealisthmus
duringswallowing and separate the nasopharynxfromthe oropharynx
Thecavity of the nasopharynx is continuous below with thecavity of the oropharynxat the pharyngeal
isthmus.
Theposition of thepharyngealisthmus is markedon the pharyngealwall by a mucosal fold caused by the
underlyingpalatopharyngeal sphincter, which is part of the superior constrictor muscle.

33. The opening ofthe
pharyngotympanictubeis posterior
tothe inferiorturbinateandslightly
abovethe level ofthe hardpalate,
andlateraltothetopofthe soft
palate.
Becausethepharyngotympanictube
projectsintothenasopharynxfroma
posterolateraldirection, itsposterior
rim formsanelevation orbulge on
the pharyngealwall.(torus tubarius)
Posteriorto thistubalelevation is a
deep recess (the pharyngealrecess).

34. Mucosal foldsrelatedtothe
pharyngotympanictubeinclude:
the small verticalsalpingopharyngealfold,
which descendsfromthe tubalelevation and
overlies salpingopharyngeusmuscle;
abroadfoldor elevation (toruslevatorius)
thatappearstoemerge fromjustunderthe
opening ofthe pharyngotympanictube,
continuesmedially ontothe uppersurfaceof
the softpalate,andoverlies thelevatorveli
palatinimuscle.

35. NASOPHARYNGEAL BURSA :
Epithelial lined medial recess extending from pharyngealmucosa to the periosteum of
basiocciput.Represent attachment of notochord to pharyngealendoderm during embryoniclife.
Abscess of this bursa is called as thornwald’s disease.
RAKTHE’S POUCH :
Remniscent of buccal mucosal invagination to formthe anterior lobe of pituitary.
Represented by dimple above adenoids.
SINUS OF MORGAGNI :
Space between the base of skulland upper border of superior constrictor
muscle.Throughthis pass auditorytube , levator palati muscle & ascending pharyngealartery
PASSAVANT’S RIDGE :
It is an elevation formedby fibres of palatopharyngeus &superior constrictor. Soft
palate makesfirm contact with theridge to cut off nasopharynx from oropharynxduring deglutition
&speech

36. ANTERIOR: Eustuchian tube
Levator palati
POSTERIOR: Pharyngealmucosa
Pharyngo-basilarfascia
Retro-pharyngealspace with Node of Rouviere
MEDIAL : Nasopharynx
SUPERIOR : Foramen lacerum
Floor of carotid canal
POSTERO-LATERAL(APEX) : Carotid canalopening
Petrous apex – posteriorly
Foramenovale
Spinosum – laterally
LATERAL: Tensor Palatini
Mandibular Nerve
Pre-styloid Compartment Of ParapharyngealSpace

39. POSTERIOR WALL : Posterioprpharyngealwalllying oppositetoc2 & c3
ANTERIOR WALL : Baseof tongue–posteriortocircumvallate papillae
Lingualtonsils
Valleculae–is adepressionlying between baseof
tongueandanteriorsurfaceofepiglottis
LATERAL WALL : Palatine(faucial)tonsil
Anteriorpillar( palatoglossalarch)
Posteriorpillar (palatopharyngealarch)
INFERIOR BOUNDARY :Upper borderofepiglottis
Pharyngoepiglotticfold

40. Theoropharynxis posteriorto theoralcavity,inferiortothe level ofthe softpalate,andsuperior
tothe uppermarginof theepiglottis .
Thepalatoglossalfolds(arches), one oneach side,thatcoverthe palatoglossalmuscles, markthe
boundarybetween theoralcavityandthe oropharynx.
The archedopening betweenthe twofoldsis theoropharyngealisthmus.
Justposteriorandmedial tothesefoldsareanotherpairof folds(arches),the palatopharyngeal
folds,one oneach side,thatoverlie the palatopharyngeusmuscles.

41. The anteriorwall oftheoropharynxinferior totheoropharyngealisthmus isformedbythe
upperpartofthe posteriorone-thirdorpharyngealpartofthe tongue.
Largecollectionsoflymphoidtissue(thelingual tonsil)arein the mucosacovering thispart
ofthe tongue
Thepalatinetonsils areonthe lateralwallsof theoropharynx.
On eachside, thereis a largeovoidcollection of lymphoidtissuein themucosalining the
superiorconstrictormuscleandbetween the palatoglossalandpalatopharyngealarches.
Thepalatinetonsils arevisible throughtheoralcavityjust posteriortothe palatoglossalfolds.

42. Whenholding liquid orsolids in the oralcavity,theoropharyngealisthmus isclosedby
depressionofthe softpalate,elevation ofthe backofthetongue,andmovement towardthe
midline ofthepalatoglossalandpalatopharyngealfolds.
This allowsapersontobreathewhile chewing ormanipulatingmaterialin theoralcavity.
On swallowing,the oropharyngealisthmusis opened, thepalateis elevated,the laryngeal
cavityis closed, andthe foodor liquidis directedintothe esophagus.
A personcannotbreatheandswallowatthesametime becausethe airwayis closed attwo
sites,thepharyngealisthmusandthelarynx.

45. Thelaryngopharynxextendsfromthe superiormarginof theepiglottis tothe topofthe
esophagusatthelevel ofvertebraC6
The laryngealinletopensintothe anteriorwall of
thelaryngopharynx.
Inferiortothe laryngealinlet,the anteriorwall
consistsofthe posteriorsurfaceofpairedarytenoid
cartilageandposteriorplateofcricoid cartilage.
The cavityofthe laryngopharynxis related
anteriorlytoapairof mucosalpouches(valleculae),
one oneach sideofthe midline, betweenthe base
ofthe tongueandepiglottis.
Thevalleculaearedepressionsformedbetween a
midline mucosalfoldandtwolateralfoldsthat
connectthe tongueto theepiglottis.

46. Thereisanotherpairofmucosalrecesses
(piriform fossae)between thecentral
partofthe larynxandthemorelateral
laminaofthe thyroidcartilage.
Thepiriformfossaeformchannelsthat
direct solidsandliquids fromtheoral
cavityaroundthe raisedlaryngealinlet
andintothe esophagus.

47. Post cricoid region
lies between theupperandlower borderofcricoid lamina.
Regiondowntothe inferiorborderofcricoid cartilage, iscalled thepharyngo-oesophageal
junction
Boundedanteriorlybyposteriorplateofcricoid cartilage.
Encirclebycricopharyngeusmusclewhich formsthe upperoesophagealsphincter.

48. Pyriform fossa
UPPERSHALLOWPART
Laterally: Thyrohyoidmembrane
Medially :Ariepiglottic fold
LOWERDEEPERPART
INFERIORLY:Paraglottic space
LATERALLY : ThyroidCartilage
MEDIALLY:Cricoid cartilage

49. the ascendingpharyngealartery;
the ascendingpalatineand tonsillar
branchesofthefacialartery;
numerousbranchesofthemaxillaryand
the lingual arteries
Arteries thatsupplythelower partsofthe
pharynxinclude pharyngealbranchesfrom
the inferiorthyroidartery,whichoriginates
fromthethyrocervicaltrunkofthe
subclavianartery
The majorbloodsupplyto thepalatine
tonsilis fromthe tonsillarbranchofthe
facialartery,whichpenetratesthe superior
constrictormuscle.

50. Lymphaticvessels fromthepharynxdrain
intothe deep cervical nodesandinclude
retropharyngeal(between nasopharynx
andvertebralcolumn),paratracheal,and
infrahyoidnodes.
The palatinetonsils drainthroughthepharyngealwall into thejugulodigastricnodesin theregion
wherethe facialvein drainsintothe internaljugularvein (andinferiorto theposteriorbelly ofthe
digastricmuscle)
Veins ofthe pharynxformaplexus, which
drainssuperiorlyintothe pterygoidplexus
in theinfratemporalfossa,andinferiorly
intothe facialandinternaljugular veins

51. Motorandmostsensoryinnervation
(except forthe nasalregion) ofthe
pharynxis mainlythroughbranchesof
thevagus[X]and
glossopharyngeal[IX]nerves, which form
aplexus in theouterfasciaofthe
pharyngealwall
Thepharyngealplexusis formedby:
the pharyngealbranchofthe
vagusnerve[X]
branchesfromtheexternal
laryngealnervefromthe Superiorlaryngeal
branchofthe vagusnerve[X]and
pharyngealbranchesofthe
glossopharyngealnerve[IX].
cranialpartofaccesorynerve

52. All muscles ofthe pharynxare
innervatedbythe vagusnerve[X]
mainlythroughthepharyngeal
plexus,except forthe
stylopharyngeus,whichis
innervateddirectlybya branchof
theglossopharyngealnerve[IX].

53. Afterexiting theskullthroughthejugular foramen,the glossopharyngealnerve[IX] descendson
the posteriorsurfaceofthe stylopharyngeusmuscle, passesontothelateralsurfaceofthe
stylopharyngeus,andthenpassesanteriorlythroughthegap between thesuperiorandmiddle
constrictorstoeventuallyreach theposterioraspectofthe tongue.
Theglossopharyngealnerve[IX] isrelatedtothe pharynxthroughoutmostof itscourse
outsidethe cranialcavity
As theglossopharyngealnerve[IX] passesunderthe freeedgeof superiorconstrictorit is just
inferiortothe palatinetonsil lying onthe deepsurfaceofthe superiorconstrictor
Pharyngealbranchestothepharyngealplexus andamotorbranchtothe stylopharyngeus
muscle areamongbranchesthatoriginatefromthe glossopharyngealnerve[IX] in theneck.
Becausesensoryinnervationoftheoropharynxisbytheglossopharyngealnerve[IX],this
nervecarriessensoryinnervationfromthepalatinetonsilandisalsotheafferentlimbofthe
'gag'reflex.

54. Soft palate

55. Mobile , flexiblepartitionb/w the
nasopharyngealairwayandoropharyngeal
foodpassage.
The softpalatecontinuesposteriorlyfrom
the edgeof thehardpalateandlaterally
bendswith thelateralwall ofthe
oropharynx.
It formstheroofofthe oropharynxandfloor
ofthe nasopharynx.
Acts asavalve thatcan be
1)depressed tohelp closethe
oropharyngealisthmus;
2) elevated toseparatethe nasopharynx
fromthe oropharynx.

56. PALATINE APONEUROSIS
Formed bytheexpandedtendonofthe
tensorpalatiwhich join in amedian raphe
Attachedtothe posterioredgeof hardpalate
andtoits interiorsurfacebehindthe palatine
crest.
Nearthe midlineit splits toenclosethe
uvularmuscle, all othermusclesattachedto
it.

57. Isthumus of the fauces
The twopalato-pharyngealfoldsif formed
fromthe baseofthe uvulatothe lateral
wall oftheoropharynx,
joinedtogethertoformpalatopharyngeal
arch
Palato-glossalfoldformedfromthe soft
palatetotheside ofthetongue,
Joinedtogethertoformthe palatoglossal
arch(which formsthe junctionofthe
buccalcavityandthe oropharynx).
This term“isthumusoffauces”is
sometimesused todescribeboththe
palatalarchestogether.

58. Fivemuscles oneach sidecontributeto theformationandmovement ofthe softpalate.
Twoofthese, tensorveli palatiniandlevatorveli palatini,descendinto thepalatefromthe
baseof theskull.
Twoothers,palatoglossusandpalatopharyngeus,ascend intothepalatefromthe tongue
andpharynx,respectively.
The lastmuscle,musculusuvulae, isassociatedwith theuvula.

59. TENSOR VELI PALATINI
Orgin :Scaphoidfossaof sphenoidbone;
fibrouspartofpharyngotympanictube;
spine ofsphenoid
Insertion:Palatineaponeurosis
Innervation:Mandibularnerve [V3]via
the branchtomedial pterygoidmuscle
Function:Tensesthe softpalate;opens
thepharyngotympanictube

60. levator VELI PALATINI
Orgin Petrouspartoftemporalbone
anteriortoopening forcarotidcanal
Insertion:Superiorsurfaceofpalatine
aponeurosis
Innervation:Vagusnerve [X]via
pharyngealbranchto pharyngealplexus
Function:Onlymuscle toelevate thesoft
palateabovethe neutralposition

61. palatopharyngeus
Orgin :Superiorsurfaceofpalatine
aponeurosis
Insertion:Pharyngealwall
Innervation:Vagusnerve[X]via
pharyngealbranchto pharyngealplexus
Function:Depressessoftpalate;moves
palatopharyngealarchtowardmidline;
elevates pharynx

62. palatoglossus
Orgin :Inferiorsurfaceofpalatineaponeurosis
Insertion:Lateralmargin oftongue
Innervation:Vagusnerve[X]via pharyngeal
branchtopharyngealplexus
Function:Depressespalate;
movespalatoglossalarchtowardmidline;
elevates backofthe tongue

63. Musculus uvulae
Orgin :Posteriornasalspine ofhardpalate
Insertion:Connectivetissue of
uvula
Innervation:Vagusnerve[X]via pharyngeal
branchtopharyngealplexus
Function:Elevatesandretractsuvula; thickens
centralregion ofsoftpalate

64. Arteries ofthe palateincludethe
greaterpalatinebranchofthe maxillary
artery,
theascendingpalatinebranchofthe facial
arteryand
thepalatinebranchof theascending
pharyngealartery.
The maxillary,facial,andascending
pharyngealarteriesareallbranchesthat
arisein theneck fromtheexternalcarotid
artery

65. Veins fromthe palategenerally
followthe arteriesandultimately
drainintothepterygoidplexus of
veins in theinfratemporalfossa,
intoa networkofveins associated
withthe palatinetonsil ( which
drainintothepharyngealplexus
ofveins ordirectlyinto thefacial
vein) .

66. Lymphatic vessels from the
palate drain into deep
cervical nodes

67. Thepalate is supplied by the
greaterand lesser palatine
nervesand the nasopalatine
nerve
General sensory fibers carriedin
all these nerves originate in the
pterygopalatine fossa from the
maxillary nerve[V2].

68. Parasympathetic(toglands)andSA(tasteon softpalate)fibersfromabranchofthe facialnerve
[VII] join thenerves in the pterygopalatinefossa,as dothesympathetics(mainly tobloodvessels)
ultimatelyderived fromthe T1spinalcordlevel.

70. CONSISTS OF
1. PHARYNGOBASILAR FASCIA
2. MUSCULAR LAYER
3. BUCCOPHARYNGEAL FASCIA

71. Thepharyngeal fascia is separatedinto two layers, which sandwich the
pharyngeal muscles between them:
a thin layer (buccopharyngeal fascia) coats the outside of the
muscular partofthe wall;
a much thicker layer (pharyngobasilar fascia) lines the inner
surface.
The fasciareinforces thepharyngealwall wheremuscleis deficient.
This isparticularlyevident abovethelevel ofthe superiorconstrictorwherethepharyngeal
wall isformedalmostentirelyoffascia
(This partof thewall isreinforcedexternallybymuscles ofthe softpalate(tensorand levator
veli palatine.
Fascia

72. MUSCULAR LAYER
CONSTRICTOR MUSCLES
Thethreeconstrictormuscles oneach sidearemajor contributorstothestructureofthe
pharyngealwall andtheir namesindicatetheirposition - superior,middle, andinferior
constrictormuscles.
Posteriorly,the muscles fromeach sidearejoinedtogetherbythepharyngealraphe.
Anteriorly,thesemuscles attachtobonesandligaments relatedtothe lateralmarginsofthe
nasalandoralcavitiesandthelarynx.
The constrictormusclesoverlap eachotherin afashionresembling thewalls ofthreeflower
potsstackedoneonthe other.
The inferiorconstrictorsoverlapthe lowermargins ofthe middle constrictorsand,in thesame
way,the middle constrictorsoverlap thesuperiorconstrictors.
Collectively, themuscles constrictor narrowthepharyngealcavity

73. Posteriorattachment: Pharyngealraphe
Anteriorattachment:
Pterygomandibular
rapheandadjacentbone onthe
mandibleandpterygoidhamulus
Innervation:Vagusnerve [X]
Function:Constrictionofpharynx
Superior constrictor
MUSCULAR LAYER
CONSTRICTOR MUSCLES

74. Whenthe superiorconstrictorconstrictsduring swallowing,it formsaprominent
ridgeon thedeep aspect ofthepharyngealwall that'catches'the marginof the
elevatedsoftpalate,whichthen sealsclosed the pharyngealisthmusbetween the
nasopharynxandoropharynx
A special bandof muscle(the palatopharyngealsphincter)originatesfromthe
anterolateralsurfaceofthe softpalateandcirclesthe inner aspectofthe pharyngealwall,
blending withthe inneraspectofthe superiorconstrictor.

75. Posteriorattachment: Pharyngealraphe
Anteriorattachment: Upper marginof
greaterhornofhyoidbone andadjacent
marginsof lesser hornandstylohyoid
ligament
Innervation:Vagusnerve [X]
Function:Constrictionofpharynx
middle constrictor
MUSCULAR LAYER
CONSTRICTOR MUSCLES
The posteriorpartof themiddle constrictorsoverlaps thesuperiorconstrictors.

76. Posteriorattachment: Pharyngealraphe
Anteriorattachment: Cricoidcartilage,
obliquelineofthyroidcartilage,anda
ligament thatspansbetween these
attachmentsandcrosses thecricothyroid
muscle
Innervation:Vagusnerve[X]
Function:Constrictionofpharynx
inferior constrictor
MUSCULAR LAYER
CONSTRICTOR MUSCLES

77. Theposterior partofthe inferior constrictors overlaps themiddle
constrictors. Inferiorly, the muscle fibers blendwith and attach into the
wall of the esophagus.
Theparts of the inferior constrictors attached to the cricoidcartilage
bracket the narrowest partof the pharyngeal cavity.

78. Posteriorly there is a small triangular interval between the upper edgeof
cricopharyngeus & lower fibres of thyropharyngeus , this interval is
sometime referredto as killian’s dehiscence.
Described as the point of weekness in the pharyngeal wall , but this is
incorrect as it is a feature of the normal anatomy of this region.
Howeverwhenthere is incordination of the pharyngeal peristaltic wave ,and
the cricopharyngeus does notrelax at the appropiate time , pressure may
temporarily build up in the lowerpart of the pharynx , in which case the most
likely place for a diverticulum to form is at killian’s dehiscence ,where the
additional support of the constrictor muscle is deficient.

80. MUSCULAR LAYER
longitudinalMUSCLES
The threelongitudinalmuscles ofthe pharyngealwallarenamedaccordingtotheir origins-
stylopharyngeusfromthestyloidprocessof thetemporalbone,salpingopharyngeusfromthe
cartilaginouspartofthepharyngotympanictube(salpinx isGreek fortube), and
palatopharyngeusfromthesoftpalate.
From theirsites oforigin, thesemuscles descend andattachinto thepharyngealwall.
The longitudinalmuscleselevate thepharyngealwall, orduring swallowing,pull the
pharyngealwall upandover abolus offoodbeing moved throughthe pharynxandintothe
esophagus.

81. Orgin :Medial side ofbaseofstyloid
process
Insertion: Pharyngealwall
Innervation:Glossopharyngealnerve
[IX]
Function:Elevationofthe pharynx
stylopharyngeus
MUSCULAR LAYER
longitudinalMUSCLES

82. Orgin :Inferioraspectofpharyngealend
ofpharyngotympanictube
Insertion: Pharyngealwall
Innervation:vagusnerve[X]
Function:Elevationofthe pharynx
salphingopharyngeus
MUSCULAR LAYER
longitudinalMUSCLES

83. Orgin :Upper surfaceofpalatine
aponeurosis
Insertion: Pharyngealwall
Innervation:vagusnerve[X]
Function:Elevationofthe pharynx
Closureoforopharyngealisthmus.
palatopharyngeus
MUSCULAR LAYER
longitudinalMUSCLES

84. Palatopharyngeusformsanimportantfoldin theoverlying mucosa(the palatopharyngeal
arch).This archis visible throughtheoralcavityandis a landmarkforfinding the palatine
tonsil, which is immediately anteriortoit on theoropharyngealwall
In additiontoelevating the pharynx,thepalatopharyngeusparticipatesin closing the
oropharyngealisthmusbydepressing thepalateandmoving the palatopharyngealfold
towardthemidline

85. Gaps betweenmuscles in the pharyngeal wall

86. Gapsbetween muscles ofthe
pharyngealwall provideimportant
routesformusclesand
neurovasculartissues
The tensorandlevator veli palatinimuscles of
the softpalateinitiallydescend fromthe base
ofthe skullandarelateralto thepharyngeal
fascia.
In thisposition,theyreinforcethepharyngeal
wall:
levator veli palatini passes through the pharyngeal fascia
inferior tothe pharyngotympanic tube andenters the soft
palate;
the tendon oftensor veli palatini turns medially around
the pterygoid hamulus andpasses through the origin of
the buccinator muscle toenter the softpalate.

87. One ofthe largestandmostimportantaperturesin thepharyngealwallis betweenthe
superiorandmiddle constrictormusclesof thepharynxandthe posteriorborderofthe
mylohyoidmuscle, whichformsthe floorofthemouth
This triangular-shapedgapnotonlyenables stylopharyngeustoslip intothe pharyngealwall,
butalsoallowsmuscles, nerves,andvessels topassbetweenregions lateralto thepharyngeal
wall andthe oralcavity,particularlythe tongue.
The gapbetween themiddleinferiorconstrictormusclesallows theinternallaryngeal
vessels andnerveaccesstotheaperturein thethyrohyoidmembraneto enterthe larynx
The recurrentlaryngealnerves andaccompanyinginferiorlaryngealvessels enterthelarynx
posteriorto thelesser hornofthehyoidbone deeptotheinferior marginofthe inferior
constrictormuscle.