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Index

TEMPORAL AND INFRATEMPORAL FOSSAE

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The temporal and infratemporal fossae are interconnected spaces on the

lateral side of the head. Their boundaries are formed by bone and soft tissues.

The temporal fossa is superior to the infratemporal fossa, above the zygomatic arch,

and communicates with the infratemporal fossa below through the gap between thezygomatic arch and the more medial surface of the skull.

The infratemporal fossa is a wedge-shaped space deep to the masseter

muscle and the underlying ramus of the mandible.

Contents:2 Muscles:Medial and lateral pterygoids, 2 Nerves:Mandibular and

horda tympani, 2 Vessels:Maxillary artery and !terygoid plexus of veins and1

ganglion: "tic ganglion.

"f the four muscles of mastication #masseter, temporalis, medial pterygoid,and lateral pterygoid$ that move the lower %aw at the temporomandibular %oint, one

#masseter$ is lateral to the infratemporal fossa, two #medial and lateral pterygoid$ are

in the infratemporal fossa, and one fills the temporal fossa #temporalis$.

Bony boundaries of the infrate!ora" fossa

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Anatoi#a" features of andib"e

Mus#"es of asti#ationThere are four muscles of mastication&

'- Temporalis

(- Masseter

)- Medial pterygoid

*- +ateral pterygoid

Te!ora"is us#"e:

Ori$in: loor of temporal fossa and deep surface of temporal fascia, inferior temporal

line.

Insertion: oronoid process and anterior border of ramus of mandible.

Ner%e su!!"y: eep temporal nerves #from the anterior division of mandibular

nerve$.A#tion: levation #anterior fibers$ and retraction #posterior fibers$ of the mandible.

Masseter us#"e:

Ori$in:+ower border and inner surface of the zygomatic arch.

Insertion:+ateral aspect of the ramus of the mandible.

Ner%e su!!"y:anterior division of the mandibular nerve.

A#tion:levation and protraction of the mandible.

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Latera" !tery$oid us#"e:

Ori$in:

/pper head& from the infratemporal surface of the greater wing of sphenoid bone.

+ower head& from the lateral surface of the lateral pterygoid plate.

Insertion:anterior aspect of the neck of the mandible and the articular disc of thetemporo-mandibular %oint.

Ner%e su!!"y:anterior division of the mandibular nerve.

A#tion:pulls the head of mandible forward during opening of the mouth #helps in

depression of mandible$, protracts the mandible and side to side moves it #chewing$.

Masseter& te!ora"is& edia" and "atera" !tery$oid us#"es

Media" !tery$oid us#"e:

Ori$in:0uperificial head& from the maxillary tuberosity.

eep head& from the medial surface of the lateral pterygoid plate.

Insertion:medial surface of the ramus of the mandible above the angle and below

mylohyoid groove.

Ner%e su!!"y:Main trunk of the mandibular nerve.

A#tion:helps in elevation of mandible, protraction of the mandible and side to side

movement.

xternal surface Medial surface

Atta#hent of us#"es of asti#ation to the andib"e

Mandibu"ar ner%e

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Course:

1 It enters the Infra-temporal fossa through the foramen ovale.

1 It has a large sensory root and a smaller motor root.

1 In foramen ovale, both roots %oin each other to form the trunk of the nerve

which is very short and rapidly divides below the foramen into anterior andposterior division.

I' Bran#hes of the trun(:

'. 2erve to medial pterygoid muscle which also supplies tensor palate and tensor

tympani muscles.

(. Meningeal branch to meninges of middle cranial fossa.

II- Bran#hes of Anterior di%ision&

#3ll its branches are motorEXCEPTthe bu##a" Ner%e$

'$ Mus#u"ar bran#hes& to masseter, lateral pterygoid and temporalis.

($ Bu##a" ner%e& It supplied the skin covering buccinators muscle. Then, it

pierces buccinators to supply the mucous membrane of the mouth in the inner

surface of buccinators.

III' Bran#hes of Posterior di%ision:

#3ll branches are sensoryEXCEPTthe mylohyoid nerve$

)* Inferior a"%eo"ar ner%e:

It innervates the lower teeth. The inferior alveolar nerve and its accompanying

vessels enter the mandibular foramen on the medial surface of the ramus of

mandible and travel anteriorly through the bone in the mandibular canal. 4efore it

enters the mandibular canal it gives motor ner%e to y"ohyoid us#"e #which

pierces sphenomandibular ligament$ and anterior be""y of di$astri# muscle.

3d%acent to the first premolar tooth, the inferior alveolar nerve divides into incisiveand mental branches&

The in#isi%e bran#hinnervates the related teeth and gum.

The enta" ner%e exits the mandible through the mental foramen and

innervates the chin and lower lip.

(. Lin$ua" ner%e:It originates in the infratemporal fossa and passes anteriorly

into the floor of the oral cavity and continues forward on the medial surface of

the mandible ad%acent to the last molar tooth at the posterior end of mylohyoid

line #dangerous position$. The lingual nerve then continues anteromedially

across the floor of the oral cavity and ascends into the tongue on the lateral

surface of the hyoglossus muscle.

+' Auri#u"o'te!ora" ner%e: It arises by two roots which encircle the middle

meningeal artery. It supplies the scalp over the temporal region.

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Mandibu"ar ner%e Bran#hes of !osterior di%ision of

and its bran#hes andibu"ar ner%e

Distribution of andibu"ar ner%e

Oti# $an$"ion: It is a parasympasytic ganglion in the infratemporal fossa below foramen ovale

medial to the main trunk of mandibular nerve.

Roots:

'. Sensory root:from mandibular nerve.

(. Sy!atheti# root:from plexus around middle meningeal artery.

). Parasy!atheti# root:lesser superficial petrosal nerve #from $"osso!haryn$ea" nerve.

"nly the parasympathetic root relays in ganglion$.

Bran#hes:

'. !arasymathetic postganglionic branches to parotid gland.

(. 0ensory branches to parotid gland.

). 0ympathetic branches to blood vessels of parotid gland.6

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- The ganglion is also traversed by the nerve to medial pterygoid which passes

through the ganglion without relay to supply tensor palati and tensor tympani.

Position& roots and bran#hes of the oti# $an$"ion

Ma,i""ary artery

Origin:

The maxillary artery originates from external carotid artery within the

substance of the parotid gland

Course:

The course of the artery is divided into ) parts according to its relation with

the lateral pterygoid muscle

)' irst !art& Medial to the neck of the mandible.

-' 0econd part& "n the lateral surface of the lateral pterygoid muscle.

+' Third part& !asses between the two heads of the lateral pterygoid to reach the

pterygopalatine fossa.

Branches:

'- Bran#hes of )st !art It gives the middle meningeal and inferior alveolar

arteries and a number of smaller branches #deep auricular, anterior tympanic,

and accessory meningeal$.

(- Bran#hes of -nd!artIt gives origin to deep temporal, masseteric, buccal, and

pterygoid branches for medial and lateral pterygoid muscles, which coursewith branches of the mandibular nerve.

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)- Bran#hes of the +rd !art #in the pterygopalatine fossa$& It gives posterior

superior alveolar, infra-orbital, greater palatine, pharyngeal, and

sphenopalatine arteries, and the artery of the pterygoid canal. the infraorbital

artery gives a. "rbital branches to the orbit. b. 3nterior superior alveolar

artery. c. Terminal branches in face #palpebral, nasal, and labial branches$.

Co""e#ti%e"y, these branches supply much of the nasal cavity, the roof of theoral cavity, upper teeth, sinuses, oropharynx, and floor of the orbit.

Ma,i""ary artery .#ourse and bran#hes/

Ptery$oid P"e,us of 0eins

Site& It is a network of veins lying around and within the lateral pterygoid

muscle.

Tributaries:

'. 5eins corresponding to the branches of the maxillary artery.

(. Inferior ophthalmic vein through the inferior orbital fissure.

). eep facial vein.

Draina$e:

The pterygoid plexus drains into the maxillary vein which unites with the

superficial temporal vein to form the retromandibular vein.

Fun#tion: It acts as a peripheral heart to aid venous return by the pumping

action of the lateral pterygoid.

Conne#tions:

It communicates with&

'. 3nterior facial vein through the deep facial vein.

(. avernous sinus via emissary veins passing through foramen ovale,

foramen spinosum and emissary sphenoid foramen.

). Inferior ophthalmic vein via a communicating vein passing through the

inferior ophthalmic fissure.

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The Ptery$oid P"e,us of 0eins

The Mouth Ca%ity

Di%isions:

The mouth cavity is divided into ( main parts&

)' 5estibule of the mouth.

-' Mouth cavity proper.

)' 0estibu"e of outh:

It is a slit like space bound externally by the lips and cheeks, internally by

gums and teeth. The vestibule opens into outside through the oral fissure. 6hen the

%aws are closed, the vestibule is connected to the mouth cavity proper through an

interval behind the last molar teeth on each side.

-' Mouth #a%ity !ro!er

It is bounded by:

)' Anterior and "atera""y:the gums and teeth.

-' Posterior"y:it communicates with the pharynx through the isthmus of fauces.

This isthmus is bounded by the palato-glossal arch on each side.

+' Roof:is formed by the hard and soft palate.

1' F"oor:is formed by the anterior (7) of the tongue.

3 median fold of mucosa connects the under surface of the tongue to the floor of

the mouth8 this is called the frenulum linguae. The floor presents a small ridge on

each side of the frenulum. This ridge is called the sublingual fold. +ateral to the

frenulum there are the lingual vein and lateral to it are the fimbriated folds #one on

each side$.

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Origin: It arises from the whole length of the mylohyoid line of mandible.

!nsertion: The posterior fibers are inserted into the body of the hyoid bone8 the

anterior fibers are inserted into a fibrous raphe in the mid line.

Nerve supply: It is supplied by mylohyoid branch of the inferior alveolar nerve.

ction: - 6hen the mandible is fixed, they elevate the floor of the mouth and hyoid

bone during the first stage of swallowing.-6hen the hyoid bone is fixed, it assists in the depression of the mandible and the

opening the mouth.

My"ohyoid us#"e 2eniohyoid us#"e

1' 2eniohyoid us#"e:

Origin: It takes origin from the inferior genial tubercle of the mandible.

!nsertion: It is inserted into the anterior surface of the body of the hyoid bone.

Nerve supply: . ' component of the hypoglossal nerve.

ction: levates the hyoid bone or depresses the mandible.

Sa"i%ary $"ands The paired parotid glands, together with the paired submandibular and

sublingual glands and the numerous small glands scattered throughout the mouth

cavity, constitute the salivary glands.

Latera" side of the head sho3in$ the sa"i%ary $"ands

The Parotid 2"and

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The parotid gland is the largest of the salivary glands.

3 small part of the facial process may be separated from

the main gland and is called the a##essory !art of the

$"and*

Sha!e and "obes and surfa#es of the $"and: The parotid gland is wedge-shaped, with its base above

and its apex behind the angle of the mandible.

It has three surfaces&

'- 0uperficial surface.

(- 3ntromedial surface.

)- !osteromedial surface.

Boundaries:

- /pwards& 9ygomatic arch.

- ownwards& 3ngle of the mandible #%ust below it$.

- 3nterior& Masseter #overlies its posterior part$.

- !osterior& 0ternomastoid #overlies its upper part$.Ca!su"es of the $"and:

The parotid gland is surrounded by a connective-tissue

capsule. In addition, the gland is enclosed in a dense fibrous capsule derived from the

investing layer of deep cervical fascia.

Parotid du#t:

The parotid duct emerges from the anterior border of the gland and passes forward

over the lateral surface of the masseter muscle. 3t the anterior border of the muscle it

turns sharply medially and pierces the buccal pad of fat and buccinator muscle. It then

opens into the vestibule of the mouth opposite the upper second molar tooth.

Surfa#e anatoy of the !arotid du#t:

- It corresponds to the middle third of a line extending between two points&

'. 3 point midway between the red margin of the upper lip and ala of the nose.

(. 3 point at the lower end of the tragus of the ear.

Position of the !arotid $"and and !arotid du#t

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Stru#tures 3ithin the !arotid $"and after its reo%a"

Stru#tures 3ithin the !arotid $"and:

)' Fa#ia" ner%e&

- The facial nerve enters the gland through the postero-medial surface. Then, it breaks

to form a plexus #pes anserinus$ inside the parotid gland.

- The plexus gives a group of terminal branches which leave the gland through&a. /pper end& Temporal branches. b. 3nterior border& 9ygomatic, buccal, and,

mandibular branches.c. +ower end& ervical branch.

-' Retroandibu"ar %einThe superficial temporal vein enters the parotid gland

through the upper end. The maxillary vein enters the gland through the antero-medial

surface. The two veins form the retromandibular vein inside the gland.

- The retro-mandibular vein leaves the gland through the lower end as anterior and

posterior branches.

+' E,terna" #arotid artery- The external carotid artery enters the gland through the

postero-medial surface. It divides inside the gland into the maxillary and superficial

temporal arteries. The superficial temporal artery leaves the gland through the upper

end. The maxillary artery leaves the gland through the antero-medial surface.1'Auri#u"ote!ora" ner%e- it enters the gland through the antero-medial surface

and leaves it through the upper pole.

4* Parotid $rou! of "y!h nodesare also located within the gland.

B"ood su!!"y:

The external carotid artery and the terminal branches within the gland, namely,

superficial temporal and maxillary arteries, supply the gland. The veins drain into

retromandibular vein.

Ly!h draina$e:

The lymph vessels drain into parotid lymph nodes and the deep cervical lymph

nodes.Ner%e su!!"y:

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Parasy!atheti#secretomotor fibers from the inferior salivary nucleus of the ninth

cranial nerve supply the parotid gland. The nerve fibers pass to the otic ganglion via

the lesser petrosal nerve. !ostganglionic parasympathetic fibers reach the parotid

gland via auriculotemporal nerve.

!ostganglionic sy!atheti#fibers reach the gland as a plexus of nerves around the

external carotid artery.Sensory:

or the capsule---------:reat auricular nerve.

or parenchyma-------3uriculo-temporal nerve.

Re"ations of the !arotid $"and:

Trans%erse se#tion in the !arotid re$ion

' The su!erfi#ia" ."atera"/ re"ationsare skin, superficial fascia containing platysma,

parotid lymph nodes and great auricular nerve.

' The !osteroedia" re"ationsare mastoid process, sternocleidomastoid, posterior

belly of the digastric, styloid process and its attached muscles, carotid sheath withinternal carotid artery, internal %ugular vein and vagus nerve, glossopharyngeal,

accessory, hypoglossal, and facial nerves.

' The anteroedia" re"ationsare the posterior border of the ramus of the mandible,

masseter and medial pterygoid muscle.

The Subandibu"ar 2"and

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The submandibular gland is a large salivary gland which lies partly under

cover of the body of the mandible and is made up of a large superficial part and a

small deep part, which are continuous with each other around the posterior border of

mylohyoid muscle.

The su!erfi#ia" !art of the $"andlies in the digastric triangle. !osteriorly, it isseparated from the parotid gland by stylomandibular ligament.

Position of subandibu"ar $"and Ner%e su!!"y of subandibu"ar& sub"in$ua"

$"ands

Re"ations of the su!erfi#ia" !art of the $"and:

'Su!erfi#ia" .inferior/ surfa#e:0kin, superficial fascia containing platysma, and

the investing layer of the deep cervical fascia, cervical branch of the facial nerve,0ubmandibular lymph nodes and anterior facial vein.

'Media" surfa#e: it is related medially to mylohyoid muscle, mylohyoid nerve and

vessels, hyoglossus muscle, lingual and hypoglossal nerves.

'Latera" surfa#e: it lies in contact with the submandibular fossa on the medial

surface of the mandible, facial artery, and medial pterygoid.

The dee! !art of the $"and extends forward in the interval between mylohyoid

below and laterally and hyoglossus and styloglossus medially.

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Position and re"ations of subandibu"ar $"and Dee! re"ations of the $"and

Re"ations of dee! !art of subandibu"ar $"and

Re"ations of the dee! !art of the $"and:

- It extends forwards between mylohyoid and hyoglossus muscles also8 it is related to

the lingual nerve above and to the hypoglossal nerve below.

Ca!su"es of the $"and:

The submandibular gland is surrounded by a connective-tissue capsule. Inaddition, the gland is partly enclosed in a dense fibrous capsule derived from the

investing layer of deep cervical fascia.

Subandibu"ar du#t:

The submandibualr duct from the medial surface of the superficial part of the

gland. It emerges from the anterior end of the deep part of the gland. It passes forward

along the side of the tongue, beneath the mucous membrane of the floor of the mouth.

It is crossed laterally by the lingual nerve #triple relation$ and then lies between the

sublingual gland and genioglossus muscle. It opens into the mouth on the summit of a

small papilla, which is situated at the side of the frenulum of the tongue.

B"ood su!!"y:

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It is supplied by branches of the facial and lingual arteries. The veins drain into the

facial and lingual veins.

Ly!h draina$e:

+ymph vessels drain into the submandibular and deep cervical lymph nodes.

Du#ts of sa"i%ary $"ands Arteria" su!!"y of subandibu"ar $"and

Ner%e su!!"y:

!arasympathetic secretomotor supply from the superior salivary nucleus of the

seventh cranial nerve #facial nerve$ via the chorda tympani nerve. !ostganglionic

parasympathetic fibers reach the gland either directly or along the duct.

!ostganglionic sympathetic fibers reach the gland as a plexus of nerves around the

facial and lingual arteries.

The Sub"in$ua" Sa"i%ary 2"and

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Position of the sa"i%ary $"ands

The sublingual gland is the smallest of the three main salivary glands. It lies

beneath the mucous membrane of the floor of the mouth, close to the midline.

Re"ations:

Media""y:it is related to genioglossus muscle, lingual nerve, and submandibular duct.

Latera""y:it is related to sublingual fossa of the medial surface of the mandible.

Su!erior"y: it is related to mucous membrane of the floor of the mouth.

Inferior"y: the gland is supported by the mylohyoid muscle.

Sub"in$ua" du#ts: The sublingual ducts are eight to twenty in number. The ma%ority

open into the mouth on the summit of the sublingual fold.

B"ood su!!"y: The gland is supplied by branches of the facial and lingual arteries.

The veins drain into the facial and lingual veins.

Ly!h draina$e: +ymph vessels drain into the submandibular and the deep cervical

lymph nodes.

Ner%e su!!"y: 0imilar to submandibular

gland.

The !a"ate

The palate forms the roof of the mouth. It is divided into&

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5ard !a"ate&

It is the bony anterior two thirds. It is composed of the palatine processes of

the maxillae and the horizontal plates of the palatine bones. It is bounded by the

alveolar arches and is continuous posteriorly with the soft palate. It forms the floor of

the nasal cavity. It is covered with mucous membrane with an inferior median rapheand bilateral corrugations on both sides.

Ora" #a%ity sho3in$ !arts of the !a"ate Mus#"es of the !a"ate

Soft !a"ate: It extends from the posterior border of the hard palate. It is covered with

mucous membrane. It ends posteriorly with the uvula and is continuous on both sides

with the lateral wall of the pharynx.

Contents of the soft !a"ate:

!alatine aponeurosis. Muscles.

2erves.

5essels.

+ymphoid

tissue.

Pa"atine a!oneurosis:

It is a fibrous sheet attached to the posterior border of the hard palate. It is the

expanded tendon of the tensor palati muscle. It splits to enclose the musculus uvulamuscle.

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Mus#"es of the soft !a"ate:

)* Tensor !a"ati us#"e:

Ori$in: It takes origin from scaphoid fossa, greater wing of sphenoid, spine of the

sphenoid and outer surface of the auditory tube #cartilaginous part$.Insertion: Its tendon hooks around the pterygoid hamulus to be inserted in the

palatine crest.

Ner%e su!!"y: Trunk of mandibular nerve.

A#tion: Tenses or tighten the soft palate.

-* Le%ator !a"ati us#"e:

Ori$in: rom ;uadrangular area on the inferior surface of the petrous part of temporal

bone and medial surface of the auditory tube #cartilaginous part$.

Insertion: It is inserted into the upper surface of palatine aponeurosis.

Ner%e su!!"y: ranial part of accessory nerve through the pharyngeal plexus.

A#tion: levation of the soft palate.

+* Pa"ato$"ossus us#"e:

Ori$in: The under surface of palatine aponurosis.

Insertion: It is inserted into the lateral side of the tongue.


A#tion: It depresses the palate, elevates the root of the tongue, and narrows the

oropharyngeal isthmus #between the mouth cavity and oropharynx$.

1* Pa"ato!haryn$eus us#"e:

Ori$in: !osterior border of the hard palate and palatine apponeurosis.

Insertion: The lamina of thyroid cartilage.


A#tion: epression of the palate and together with the soft palate it narrows the

nasopharyngeal isthmus during deglutition.

4* Mus#u"us u%u"ae:

Ori$in: rom posterior nasal spine.

Insertion: It is inserted into mucous membrane of the uvula.


A#tion:

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Media" side of the head sho3in$ us#"es of !a"ate

Ner%e su!!"y of the !a"ate:

A' Sensory ner%e su!!"y:

)* :reater palatine nerve. =ard palate

-*2asopalatine nerve

+* +esser palatine nerve. 0oft palate

1* :lossopharyngeal nerve.

- Se#retootor fibres to the !a"atine $"ands:

The facial nerve through its greater petrosal nerve relays in the sphenopalatine

ganglion. !ostganglionic fibers reach the palatine glands through the lesser palatine

nerves.

- Taste sensation:

Taste fibers reach the inferior surface of the palate through the lesser palatine nerves.

B' Motor ner%e su!!"y:

3ll the muscles are supplied by the cranial part of accessory nerve except the tensor

palati muscle which is supplied by the mandibular nerve.

Arteria" su!!"y of the !a"ate:

)* :reater palatine artery #branch from the maxillary artery$.

-* 3scending palatine artery #branch from the facial artery$.

+* !alatine branch of ascending pharyngeal artery.

0enous draina$e of the !a"ate: Through pterygoid and pharyngeal plexuses of veins.

Ly!hati# draina$e of the !a"ate:

)* The hard palate drains into submandibular lymph nodes.

-* The soft palate drains into upper deep cervical and retropharyngeal lymph nodes.

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The Ton$ue

It is a mass of striated muscles covered with mucous membrane.

Parts:

It is formed of & tip > dorsal and ventral surfaces > root.

The u#ous ebrane of the ton$ue:

The dorsal surface of the anterior two thirds #oral part$ is separated from the

posterior third #pharyngeal part$ by a 5 shaped sulcus, the sulcus terminalis. The apex

of the sulcus is marked by a small pit #the foramen caecum$.

The anterior surface is covered with papillae #filiform, fungiform and vallate$,

6hile the posterior surface is devoid of papillae and contains aggregations of

lymphoid tissue #lingual tonsil$.

The mucous membrane of the inferior surface of the tongue is smooth and

reflected to the floor of the mouth, and is connected to it by the frenulum.

"n both sides lie the lingual artery, lingual nerve, and deep lingual vein #frommedial to lateral$. +ateral to the lingual vein the mucous membrane forms a fringed

fold #plica fimbriata$.

Mus#"es of the ton$ue:

The muscles of the tongue are divided into two types&

)* Intrinsi# us#"es: They are confined to the tongue and not attached to bone. They

are supplied by the hypoglossal nerve. They change the shape of the tongue as

narrowing the tongue #by transverse muscle$, 0hortening #by longitudinal muscle$,

Thinning #by vertical muscle$.

Dorsu of the ton$ue sho3in$ its u#ous ebrane

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Sa$itta" se#tion of the head sho3in$ E,trinsi# us#"es of ton$ue

intrinsi# us#"es of ton$ue

-* E,trinsi# us#"es:

They change the position of the tongue

)' Sty"o$"ossus us#"e:

Origin: 0tyloid process of the temporal bone.

!nsertion: The side of the tongue.

Nerve supply: =ypoglossal nerve.

ction: It draws the tongue upwards and backwards.

-' Pa"ato$"ossus us#"e:

It is described with the palate.

+' 2enio$"ossus us#"e:It is a flat fan shaped muscle which lies close to its fellow of the opposite side.

Origin: 0uperior genial tubercle of the mandible.

!nsertion: The whole length of the tongue.


ction: 6ith the opposite muscle it protrudes the tongue. They also depress the

median part of the tongue.

1' 5yo$"ossus us#"e:

It is a ;uadrilateral muscle.

Origin: It takes origin from the lateral part of the body and whole length of the

greater horn of hyoid bone.!nsertion: It is inserted into the side of the tongue lateral to the hyoglossus muscle.


ction: epression of the tongue.

Ner%e su!!"y of the ton$ue:

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It is a musculomembranous tube present posterior to the nose, mouth, and

larynx. It extends from the base of the skull to the sixth cervical vertebra, where it

%oins the oesophagus. The wall of the pharynx is composed of&

)* +ining mucous membrane.

-* The inner fibrous coat #pharyngobasilar fascia$ which is attached to the base of the

skull superiorly and blends with the wall of the oesophagus inferiorly.+* The muscles of the pharynx.

1* The outer fibrous coat #buccopharyngeal fascia$.

Mus#"es of the !haryn,:

)' Su!erior #onstri#tor us#"e:

Ori$in:lower part of the posterior border of the medial pterygoid plate, pterygoid

hamulus, pterygomandibular raphe and posterior end of the mylohyoid line of the

mandible.

!nsertion: Into the pharyngeal tubercle and the median fibrous pharyngeal raph.

Nerve supply:!haryngeal plexus.

-' Midd"e #onstri#tor us#"e:Origin: +ower part of the stylohyoid ligament and lesser and greater horns of the

hyoid bone.

!nsertion: Its fibres radiate medially to be inserted into the median fibrous pharyngeal

raphe.

Nerve supply: !haryngeal plexus.

+* Inferior #onstri#tor us#"e:

Origin: "bli;ue line of thyroid cartilage and the side of the cricoid cartilage.

!nsertion: It overlaps the lower surface of the middle constrictor muscle and is

inserted into the median pharyngeal raphe.

Nerve supply: !haryngeal plexus

Latera" side of the ne#( sho3in$ us#"es of !haryn,

ction o" constrictor #uscles:

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- uring the process of swallowing contraction of the upper fibres of the superior

constrictor will pull the pharyngeal wall forwards. This will aid the soft palate in

closure of the nasopharyngeal isthmus #between the nasopharynx and oropharynx$.

- The successive contractions of the superior, middle and inferior constrictor muscles

propel the bolus of food downwards to the oesophagus.

1* Sty"o!haryn$eus us#"e:

Origin: It takes origin from styloid process of the temporal bone.

!nsertion: It is inserted into the posterior border of thyroid cartilage.

Nerve supply: :lossopharyngeal nerve.

ction:levation of the larynx and pharynx during swallowing.

4* Sa"!in$o!haryn$eus us#"e:

Origin: It takes origin from the inferior surface of the cartilaginous part of auditory

tube.

!nsertion: It blends with the palatopharyngeus muscle.

Nerve supply: !haryngeal plexus.ction: It assists in elevation of the pharynx.

6* Pa"ato!haryn$eus us#"e:

It has been discussed with the palate.

The interior of the !haryn,:

The !haryn, is di%ided into three !arts:

)' Naso!haryn,

-' Oro!haryn,

+' Laryn$o!haryn,

)' Naso!haryn,:

- It extends from the base of the skull to the upper surface of the soft palate #at

level of . '$. It is discussed with the respiratory system.

-' Oro!haryn,:- It extends from the lower surface of the soft palate to the upper border of the

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epiglottis.

- It communicates anteriorly with the oral cavity by an opening called the

oropharyngeal

isthmus made by the palatoglossal arch on each side #each arch is made by

palatoglossus muscle covered by mucous membrane$.

- It also contains the palatopharyngeal arch #made by palatopharyngeus musclecovered by mucous membrane$.

- 4etween the palatoglossal and palatopharyngeal arches there is the ?palatine

tonsil@.

Sa$ita" se#tion of the head sho3in$ the interior of oro'!haryn,

Pa"atine tonsi"s

They are two masses of lymphoid tissue in the lateral wall of the oropharynx.

They are covered with mucous membrane. Its medial surface pro%ects into the lumen

of the oropharynx. Its surface is pitted by numerous small openings which lead into

the tonsi""ar #ry!ts. The upper part of the medial surface has a deep intratonsi""ar

#"eft. It is covered on its lateral surface by a #a!su"e.

Re"ations of the !a"atine tonsi"s:

3nteriorly& !alatoglossal arch.

!osteriorly& !alatopharyngeal arch.

0uperiorly& 0oft palate.

Inferiorly& !osterior third of the tongue.

Medially& avity of the oropharynx.

+aterally #tonsillar bed$& 0uperior

constrictor muscle, paratonsillar vein

and tonsillar artery.

Arteria" su!!"y of the tonsi":

'- Tonsillar artery .fro fa#ia" artery/*

(- 3scending palatine artery #from facial artery$.

)- +ingual artery #from external carotid artery$.*- 3scending pharyngeal artery #from external carotid artery$.

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0enous draina$e: !aratonsillar vein

Ner%e su!!"y of the tonsi"s:

)*:lossopharyngeal nerve* -*+esser palatine nerve*

Ly!hati# draina$e of the tonsi": eep cervical lymph nodes #mainly the %ugulo-

digastric nodes$.

+' Laryn$o!haryn,:

- It extends from the upper border of the

epiglottis to the level of the cricoid cartilage

#level of . A$ where it continues as the

oesophagus.

- Its upper part lies behind the inlet of the

larynx.

B !yriform fossa&- It is a depression on each side of the

inlet of the larynx.

- It has the following boundaries&

a. Medial& 3ryepiglottic fold of the larynx.

b. +ateral& Thyrohyoid membrane above

and the lamina of the thyroid cartilage below.

- The nerve supply of the mucous membrane

of the pyriform fossa is the internal laryngeal

nerve.

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Laryn$o!haryn,

2a!es of the !haryn,:

'. 3 gap between the upper border of the superior constrictor and the skull base

- This gap is occupied by the pharygobasilar fascia.

- It gives passage to levator palati, ascending palatine artery, and auditory tube.

(. 3 gap laterally between the superior and middle constrictors

- It gives passage to the following& a. 0tylopharyngeus passing down to the pharynx.

b. :lossopharyngeal nerve passes forwards to the tongue.

). 3 gap laterally between the middle and

inferior constrictors

- This gap is closed by the thyrohyoid

membrane.

- The structures passing through this gap are&

a. Internal layryngeal nerve. b.

0uperior laryngeal artery.

*. 3 gap between the two parts of the inferior

constrictor

- It is a weak area at the back of the pharynx

called #CillianDs dehiscence$

E. 3 gap at the lower border of the inferior

constrictor

- It is pierced by&

a. Inferior laryngeal artery. b.

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It is supplied mainly by the pharyngeal plexus which is composed of&

'- The glossopharyngeal nerve.

(- The pharyngeal branch of the vagus nerve #carrying fibres of cranial accessory nerve$.

)- 4ranches of the superior cervical sympathetic ganglion.

Motor ner%e su!!"y:Through the pharyngeal plexus #by cranial part of accessory nerve$ except the

stylopharyngeas muscle which is supplied by the glossopharyngeal nerve.

Sensory ner%e su!!"y:

- Mucous membrane of the nasopharynxis supplied by Maxillary nerve.

- Mucous membrane of the oropharynxis supplied by :lossopharyngealnerve.

- Mucous membrane of the laryngopharynx is supplied by internal laryngeal branch

of the vagus nerve.

Arteria" su!!"y of the !haryn,:

- 3scending pharyngeal artery.- 3scending palatine artery.

- acial and lingual arteries.

0enous draina$e of the !haryn,:

!haryngeal plexus of veins which drains into the internal %ugular vein.

Ly!hati# draina$e of the !haryn,:

- eep cervical lymph nodes. -

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'-

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Fas#ia of the Anterior Abdoina" 7a""

Mus#"es of anterior abdoina" 3a"":

Mus#"e Ori$in Insertion A#tion Inner%ation

xternal

abdominal

obli;ue

xternal surface of

lower ribs.

Its fibers are

directeddownwards,

forwards and

medially.

4y an apponeurosis

into linea alba, pubic

crest K tubercle,

anterior superior iliacspine K anterior half

of iliac crest.

lexes and

laterally bends the

trunk

Intercostal nerves H-

'', subcostal,

iliohypogastric and

ilioinguinal nerves

Internal

abdominal

obli;ue

Thoracolumbar

fascia, anterior (7)

of the iliac crest,

lateral (7) of the

inguinal ligament.

Its fibers are

directed upwards,forwards and

medially.

+ower ) or * ribs,

linea alba, pubic crest

and pectin. Its lower

fibers form an arch

called con%oint

tendon.

lexes and

laterally bends the

trunk


'', subcostal,

iliohypogastric and

ilioinguinal nerves

Transversus

abdominis

Inner surface of the

lower A ribs,

thoracolumbar

fascia, anterior (7)

of the inner lip of

iliac crest, lateral

'7) of inguinal

ligament.

+inea alba, pubic

crest and pectin. Its

lower fibers form an

arch together with the

lower fibers of

internal obli;ue

called con%oint

tendon.

lexes and

laterally bends

trunk


'', subcostal,

iliohypogastric and

ilioinguinal nerves

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around the spermatic

cord and testis #or

around the distal

portion of the round

ligament of the

uterus$

Notes:

The inguinal ligament is the infolded lower part of the external abdominal obli;ue

aponeurosis. The external spermatic fascia is the external abdominal obli;ue

muscleJs contribution to the coverings of the testis and spermatic cord.

'.

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Mus#"es of anterior abdoina" 3a""

Mus#"es of anterior abdoina" 3a""

Re#tus Sheath:

Definition:'

It is a fibrous envelope that surrounds rectus abdominis muscle formed by the

aponeurosis of the anterior abdominal wall muscles.

Foration:

'$ The internal obli;ue muscle splits for a greater part of its length into anterior

and posterior layers.

($ The anterior layer fuses with the aponeurosis of the external obli;ue to form

the anterior 3a"" of the re#tus sheath, while the posterior layer fuses with the

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aponeurosis of the transversus abdominis to form the !osterior 3a"" of the

re#tus sheath*

7a""s of the re#tus sheath:'

The wall of the rectus sheath is subdivided into three !artsby t3o "ineswhich are&

'. +ine midway between theubi"i#us and the,i!hoid !ro#ess.

(. +ine midway between theubi"i#us and the

sy!hysis !ubis*

#3$/pper part&-

3nterior wall formed by& 3poneurosis of the

external obli;ue muscle.

!osterior wall formed by& The Eth, Athand Hth

costal cartilage.

#4$ Middle part&-

3nterior wall formed by &

'. 3poneurosis of external obli;ue.

(. The anterior layer of the aponeurosis of internal

obli;ue

!osterior wall formed by &

'. !osterior wall of the aponeurosis of internal

obli;ue. Trans%erse se#tion of re#tus sheath

(. 3poneurosis of the transversus abdominis.

#$ +ower part&-

3nterior wall formed by &

'. 3poneurosis of external obli;ue.

(. 3poneurosis of internal obli;ue.

). 3poneurosis of the transversus abdominis.

!osterior wall formed by& ascia transversalis. The posterior wall ends here

forming an arched border called the ar#uate "ine.

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Anterior and !osterior 3a""s of re#tus sheath

Contents of re#tus sheathContent of the re#tus sheath:'

'. Two muscles '$

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epigastric artery.

(. Musculophrenic artery #from the internal thoracic artery$.

). +ower two posterior intercostal and subcostal arteries #from the descending

thoracic aorta$.

*. Inferior epigastric artery #from the external iliac artery$. - It passes medial to the deep inguinal ring then it pierces fascia transversalis to

enter the rectus sheath in front of the arcuate line.

- It ends by anastomosing with the superior epigastric artery.

- It gives the following branches, pubic branch, cremasteric branch #supplies

cremaster muscle$ and muscular branches.

E. eep circumflex iliac artery #from the external iliac artery$

- It gives the following branches, ascending branch, anastomotic branch and

muscular branches.

A. 0uperficial branches of the femoral artery which are superficial epigastric artery,

superficial circumflex iliac artery, and superficial external pudendal artery.

H. +umbar arteries #from the descending abdominal aorta$.

Arteries of anterior abdoina" 3a""

Ner%e Su!!"y of Anterior Abdoina" 7a""&

- The anterior abdominal wall muscles and the overlying skin are supplied by&

I. +ower five intercostal and subcostal nerves&

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- They run in the costal groove #the subcostal nerve runs below the last rib$.

- Then, they pass between the costal origin of the diaphragm and transversus

abdominis muscle.

- More laterally, they pass between transversus abdominis and internal obli;ue

muscles.- inally, they pierce the posterior wall of the rectus sheath, rectus abdominus, and

the anterior wall of the rectus sheath to terminate as the anterior cutaneous nerves.

II. Iliohypogastric and ilioinguinal nerves&

- 4oth nerves pierce psoas ma%or where they appear on its lateral border, then they

pass between the kidney and ;uadratus lumborum.

- Then, they pierce transversus abdominis and pass between it and internal obli;ue

where they supply both muscles #the ilioinguinal nerve pierces it close to the anterior

superior iliac spine which is the site of the appendicectomy$.

- inally, they pierce internal obli;ue and pass between it and external obli;ue where

they supply both muscles.

B The iliohypogastric nerve pierces the aponeurosis of external obli;ue two inches

above the medial part of the inguinal ligament to supply the overlying skin.

B The ilioinguinal nerve passes through the superficial inguinal ring to supply the

skin of the upper part of the medial side of the thigh and the skin of the anterior part

of the scrotum or labia ma%ora.

Inner%ations of anterior abdoina" 3a""

Ly!hati#s of anterior abdoina" 3a"":

Ly!hati#s in the re$ion abo%e the ubi"i#us aredrained into the axillary

lymph nodes.

Ly!hati#s in the re$ion be"o3 the ubi"i#usare drained into the superficial

inguinal nodes.

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The In$uina" #ana"

It is an obli;ue inter-muscular slit * cm long above the medial half of inguinal

ligament.

It begins at the deep inguinal ring and terminates at the superficial ring.

In$uina" rin$s:

Su!erfi#ia" in$uina" rin$:

It is a triangular opening in the aponeurosis of the external obli;ue muscle that

lies %ust lateral to the pubic tubercle.

Dee! in$uina" rin$:

It lies in the transversalis fascia, %ust lateral to the inferior epigastric vessels. It

is half an inch above the midpoint of inguinal ligament.

Boundaries:

3nterior wall& aponeurosis of the external obli;ue muscle along the whole

length of the canal and fleshy fibers of internal obli;ue muscle along the lateral

'7( of the canal.

!osterior wall& it is formed by transversalis fascia along the whole length of the

canal, con%oint tendon along medial '7( and reflected ligament along medial

'7*.

0uperior wall #roof$& arching fibers of the internal obli;ue and transverse

muscles.

Inferior wall #floor$& inguinal and lacunar ligaments.

ontents& it transmits the spermatic cord or the round ligament of the uterus

and the genital branch of the genitofemoral nerve, both of which also runthrough the deep inguinal ring and the inguinal canal. 3n indirect inguinal

hernia #if present$ also passes through this canal.

In$uina" #ana"& #ontents and boundaries

In$uina" trian$"e:

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On ea#h side:'(th

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Mus#"es of !osterior abdoina" 3a""

The Abdoina" aorta

The abdominal aorta is the largest artery in the abdominal cavity.

It is a direct continuation of descending thoracic aorta. It is ') cm long. It enters the abdomen opposite '( th thoracic vertebra through aortic opening of

the diaphragm. It ends by dividing into ( common iliac arteries opposite the

*th lumbar vertebra.

Anterior re"ations of aorta and inferior %ena #a%a

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Anterior view

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Re"ations of abdoina" aorta:

Anterior re"ations fro su!erior to inferior:

eliac ganglia and plexus.

4ody of the pancreas.

0plenic and left renal veins.

#)rdpart$ part of the duodenum.

0uperior mesenteric vessels and root of mesentery.

Posterior re"ations:

+umbar vertebrae #'-*$ and intervertebral discs.

3nterior longitudinal ligament.

)rdand *thlumbar veins.

On the ri$ht:

3zygos vein.

isterna chyle and thoracic duct.

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Bran#hes of abdoina" aorta:

Bran#h 0ertebra" "e%e" Paired or sin$"e

inferior phrenicarteries +' #upper border$ !aired

coeliactrunk +' #upper border$ 0ingle

superior mesentericartery +' #lower border$ 0ingle

middle suprarenalarteries +' #lower border$ !aired

renalarteries +( !aired

gonadalarteries +) !aired

four lumbararteries +'-+* !aired

inferior mesentericartery +) 0ingle

median sacralartery +*0ingle

common iliacarteries +* !aired

N*B*4ifurcation #union$ of the inferior vena cavais at +E #below that of the

bifurcation of the aorta$.

Bran#hes of aorta

Coon I"ia# Arteries:

1 The abdominal aorta divides, on the left side of the body of the fourth lumbar

vertebra, into the two common iliac arteries.

1 ach artery ends in front of sacro- iliac %oint by dividing into external and

internal iliac arteries.

45
http://en.wikipedia.org/wiki/Inferior_phrenic_arteryhttp://en.wikipedia.org/wiki/Inferior_phrenic_arteryhttp://en.wikipedia.org/wiki/Celiac_trunkhttp://en.wikipedia.org/wiki/Superior_mesenteric_arteryhttp://en.wikipedia.org/wiki/Middle_suprarenal_arteryhttp://en.wikipedia.org/wiki/Renal_arteryhttp://en.wikipedia.org/wiki/Renal_arteryhttp://en.wikipedia.org/wiki/Gonadal_arteryhttp://en.wikipedia.org/wiki/Gonadal_arteryhttp://en.wikipedia.org/wiki/Lumbar_arterieshttp://en.wikipedia.org/wiki/Lumbar_arterieshttp://en.wikipedia.org/wiki/Inferior_mesenteric_arteryhttp://en.wikipedia.org/wiki/Median_sacral_arteryhttp://en.wikipedia.org/wiki/Common_iliac_arteryhttp://en.wikipedia.org/wiki/Inferior_vena_cavahttp://en.wikipedia.org/wiki/Inferior_phrenic_arteryhttp://en.wikipedia.org/wiki/Celiac_trunkhttp://en.wikipedia.org/wiki/Superior_mesenteric_arteryhttp://en.wikipedia.org/wiki/Middle_suprarenal_arteryhttp://en.wikipedia.org/wiki/Renal_arteryhttp://en.wikipedia.org/wiki/Gonadal_arteryhttp://en.wikipedia.org/wiki/Lumbar_arterieshttp://en.wikipedia.org/wiki/Inferior_mesenteric_arteryhttp://en.wikipedia.org/wiki/Median_sacral_arteryhttp://en.wikipedia.org/wiki/Common_iliac_arteryhttp://en.wikipedia.org/wiki/Inferior_vena_cava

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E,terna" i"ia# Arteries:

1 "ne of the two terminal branches of the common iliac artery.

1 ach begins at the sacro-iliac %oint.

1 It leaves the abdomen by passing behind the mid-inguinal point where it

becomes the femoral artery.1 4ranches& inferior epigastric artery and deep circumflex iliac artery.

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Inferior %ena #a%a .I0C/

1 It is the largest vein in the body. It is formed by union of two common iliac veins

anterior to and %ust to the right of E thlumber vertebra.

1 It ascends on the right side of aorta, passes in the vena cava opening of diaphragm

opposite T and drains into the right atrium.

1 It conveys blood from the whole body below the diaphragm to the right atrium.

Posterior re"ations:

+ower part& is related to vertebral column, anterior longitudinal ligament, rightsympathetic trunk.

/pper part& is related to right crus of the diaphragm, right renal artery, right middle

suprarenal artery, right suprarenal gland, right celiac ganglion and right phrenic

artery.

Anterior re"ations:

!osterior surface of the liver, 'stpart of the duodenum, head of the pancreas, )rdpart of

the duodenum, right gonadal and common iliac arteries, peritoneum and coils of the

small intestine.

Tributaries of I*0*C:'

'. Two common iliac veins&

- they unite together forming

I.5..

(. Two pairs of lumbar veins&

- )rd, *th.

). Two renal veins #

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Inferior %ena #a%a and its tributaries

Ner%es of !osterior abdoina" 3a""

0everal important components of the nervous system are in the posterior

abdominal region. These include the sympathetic trunks and associated splanchnic

nerves, the plexus of nerves and ganglia associated with abdominal aorta, and lumberplexus of nerves.

Sy!athati# Trun(:

1 Two long ganglionated nerve strand one on each side of the vertebral column.

1 It extends from the base of the skull to the coccyx.

1 It enters the abdomen deep to the medial arcuate ligament of the diaphragm.

1 It lies along the medial border of psoas ma%or. 3nteriorly on the right side, it lies

behind the I.5.. and on the left side, it lies along the left side of the aorta.

1 It passes inferiorly behind common iliac vessels.

1 Its termination is by %oining to form unpaired ganglion impar #anterior to sacrum$.

ach trunk has four ganglia and receives a white ramus from each of the upper

two or three lumber nerves and sends grey rami to each of the five lumber nerves to

be distributed with nerves to somatic structures. our rami, the lumber splanchnic

nerves, run medially to the inter-mesentric and superior hypogastric plexuses to be

distributed with blood vessels to viscera.

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Sy!athati# trun( and !re%ertebra" !"e,uses and $an$"ia

Lubar !"e,us:

ormation& formed by anterior rami of +'-+), and upper part of +*.

!osition& lies within substance of psoas ma%or. Therefore, relative to the psoas

ma%or muscle the various branches emerge either&

3nterior N genitofemoral nerve8

Medial N obturator nerve and lumbosacral trunk

+ateral- iliohypogastric, ilioinguinal, femoral nerve and lateral cutaneous

nerve of the thigh.

The i"iohy!o$astri# ner%e

The iliohypogastric nerve is formed by fibers from +'. It supplies the skin over the

lateral gluteal region and the skin above the pubis.

The i"ioin$uina" ner%e

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The ilioinguinal nerve is formed in common with the iliohypogastric nerve. It

passes through the superficial inguinal ring.

The $enitofeora" ner%e

The genitofemoral nerve is formed from +', ( and passes through the psoas to emerge

on its anterior surface. It runs downwards on the psoas and divides into genital and femoral

branches. The genital branch enters the inguinal canal through the deep inguinal ring to

supply the cremasteric muscle and a small area of overlying skin. The femoral branch

passes behind the inguinal ligament to enter the femoral sheath and supply the skin over the

femoral triangle.

Latera" #utaneous ner%e of the thi$h

The lateral cutaneous nerve of the thigh emerges at the lateral border of the psoas

muscle. It is formed from the posterior division of the +(,) anterior primary rami. It

supplies the skin on the lateral part of the thigh.

The feora" ner%e

The femoral nerve arises from posterior division of the +(,),* anterior primary rami.

The nerve lies between psoas and iliacus and enters the thigh behind the inguinal ligament.The obturator ner%e

The nerve arises from anterior division of the +(,),* anterior primary rami. It emerges

medial to the psoas muscle and leaves the pelvis through the obturator foramen.

The "ubosa#ra" trun(

3 part of the anterior division of the +* primary ramus and the +E primary ramus form the

lumbosacral trunk. The trunk lies anterior to the ala of the sacrum to %oin the 0' anterior

primary ramus.

Mus#u"ar ner%es

The T'( and lumbar primary rami send short nerves into neighboring muscles8 the

;uadratus lumborum, and psoas.

Bran#hes of "ubar !"e,us

Thora#o'"ubar fas#ia:

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This is strong fascia which covers the muscles of the back and trunk. It is also called

lumber fascia because it is well developed in the lumbar region, but it extends

upwards to the neck and downward to the sacrum.

It is formed of three layers in the lumbar region&

a. 3nterior layer& lies infront of ;uadratus lumbrum muscle and is attached to the

anterior surface of transverse processes of lumbar vertebrae.b. Middle layer& it covers the posterior surface of ;uadratus lumbrum muscle and

is attached to the tip of transverse processes of lumbar vertebrae.

c. !osterior layer& It covers the deep muscles and is attached to lumbar spines.

Trans%erse se#tion of abdoen sho3in$ the thora#o"ubar fas#ia

The Peritoneu

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'To understand the extent of the greater sac, it is followed in a vertical direction.

ollowing the peritoneum on the inner aspect of the anterior abdominal wall in an

upward direction, a sickle shaped fold of peritoneum connects the anterior abdominal

wall with the liver to the right of the median plane. "n the right side of the falciform

ligament, the peritoneum continues on the under surface of the diaphragm. Then, it isreflected from the under surface of the diaphragm on to the superior surface of the

liver. This reflection is called the u!!er "ayer of #oronary "i$aent.

- The peritoneum passes from the upper surface of liver to its anterior surface, then to

its inferior surface. rom the posterior part of the inferior surface, the peritoneum is

reflected to the front of right kidney and suprarenal gland. This reflection is called the

"o3er "ayer of #oronary "i$aent*These two layers of coronary ligament bound the

bare area of the "i%er which has no peritoneal covering.

- ollowing the upper and lower layers of coronary ligament to the right shows that

they meet at the apex of bare area to form the ri$ht trian$u"ar "i$aent*

- rom the front of right kidney, the peritoneum passes to the front of the duodenum

and right colic flexure. Oust above the duodenum, the peritoneum passes medially in

front of inferior vena cava to form the posterior boundary of the e!i!"oi# foraen*

- If the stomach is reflected away from the liver, a peritoneum fold ."esser

oentu/is found connecting the liver with the stomach which is formed by two

layers. The two layers of peritoneum separate to enclose the stomach. Then, they

come close together at the greater curvature of stomach to form a big peritoneal fold

.$reater oentu/. The two layers of greater omentum descend down and then recur

up to be attached to the anterior border of pancreas.

- The peritoneum of greater sac passes down from the anterior border of the pancreas

to form another peritoneal fold .trans%erse eso#o"on/to enclose the transverse

colon.

- rom the anterior border of pancreas, the peritoneum passes down to cover the

inferior surface of body of pancreas, duodenum and structures found in the posterior

abdominal wall.

- !eritoneum covering the posterior abdominal wall makes a reflection along the

course of superior mesenteric artery to enclose the free part of small intestine

.esentery of sa"" intestine/*

- The peritoneum continues down to continue into the pelvis to form the pelvic

peritoneum.

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Sa$itta" se#tion of the abdoen sho3in$ Trans%erse se#tion of the

atta#hent of fa"#ifor "i$aent* abdoen sho3in$ the

atta#hent of esentry*

Atta#hents of the $reater Anterior %ie3 of abdoina" #a%ity

and "esser oentu sho3in$ atta#hent of esentery

and trans%erse eso#o"on

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Atta#hent of !eritoneu on the different surfa#es of the "i%er

Peritonea" ref"e#tions in horionta" se#tion:

- the peritoneum covers the inner aspect of the anterior abdominal wall and reflects in

a horizontal pattern to form gastrosplenic, lienorenal, lesser omentum, falciform

ligaments of the liver.

Lesser sa#:

This is a diverticulum from greater sac8 it extends down behind the stomach as far as

the transverse mesocolon and is bounded below the stomach by the greater omentum.

The opening of the lesser sac #e!i!"oi# foraen$ lies behind the free edge of the

lesser omentum.

Boundaries of the e!i!"oi# foraen:

Posterior:the inferior %ena #a%alies immediately behind the posterior peritoneum.

Su!erior:the inferior surface of the liver, the #audate !ro#ess.

Inferior:the first !art of the duodenu.

Anterior:the free edge of the lesser omentum8 in which the !orta" %ein "ies behind& the #oon

bi"e du#t in front and the he!ati# artery in front on the "eft of the bi"e du#t*

Re"ations of the "esser sa#:

The lesser sac has t3o 3a""s& anterior and posterior, and four borders:upper,

lower, left and right.

Anterior 3a""& It is formed by&

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The lesser omentum.

!eritoneum covering the posterior surface of the stomach K first part of

duodenum.

3nterior two layers of the greater omentum.

Posterior 3a"": Its lower part is formed by the posterior two layers of the greater

omentum, while its upper part is formed by peritoneum covering structures on the

posterior abdominal wall which include&

4ody of the pancreas.

/pper part of abdominal aorta.

eliac artery and its branches.

iaphragm.

+eft kidney.

+eft suprarenal gland.

;!!er border: It is formed by reflection of peritoneum between liver and the

diaphragm.

Lo3er border: It is formed by the inferior margin of the greater omentum where the

anterior two layers become continuous with the posterior two layers.

Left border: formed by the gastrosplenic K lienorenal ligaments.

Ri$ht borderthe epiploic foramen #foramen of 6inslow$.

The Stoa#h

Site:

The stomach is situated in the left hypochondriac, epigastric and umbilical regions

of the abdomen. It is O-shaped organ and has t3o orifi#es, the cardiac and pyloric

orifices, t3o #ur%atures, the greater and lesser curvatures, and t3o surfa#es, an

anterior and a posterior surface.

Parts of the stoa#h:'- Fundus:is dome-shaped and pro%ects upward and to the left of the cardiac

orifice. It is usually full of gas.

(- Body:extends form the fundus to a line extending from the incisura angularis

on the lesser curvature to the prepyloric bulge on the greater curvature.

)- !y"ori# !art: it is lower part of the stomach. It has three parts #pyloric antrum,

pyloric canal and pyloric sphincter$.

Cur%atures of the stoa#h:

)' Lesser #ur%ature:forms the right border of the stomach and extends from the

cardiac orifice to the pylorus. The lesser omentum extends from the lesser

curvature to the liver. It is related to the right and left gastric vessels.

-' 2reater #ur%ature:forms the left border of the stomach and extends fromthe cardiac orifice to the pylorus. It gives attachment to gastrophrenic,

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gastrosplenic and greater omentum from above downwards. It is related to

right and left gastroepiploic vessels.

Orifi#es of the stoa#h:

)' Cardia# orifi#e:is ) in#hto the left of the median plane at level of T*)

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Stru#tures forin$ the stoa#h bed

B"ood su!!"y of the stoa#h:

)' Arteria" su!!"y to the stoa#h:

These are derived from the bran#hes of the #e"ia# trun(.

a. Left $astri# arteryarises from the celiac artery.

b. Ri$ht $astri# arteryarises from the hepatic artery.

c. Short $astri# arteriesarise from the splenic artery.

d. Left $astroe!i!"oi# arteryarises from the splenic artery.

e. Ri$ht $astroe!i!"oi# arteryarises from the gastroduodenal branch of

the hepatic artery.

-' 0enous draina$e of the stoa#h:

The "eft and ri$ht $astri# %einsdrain directly into the portal vein.

The short $astri# %einsand the "eft $astroe!i!"oi# %ein%oin the splenic vein

The ri$ht $astroe!i!"oi# %ein%oins the superior mesenteric vein.

Ly!h draina$e of stoa#h:

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- The gastric lymph vessels drain ultimately into the celiac lymph nodes.

Ly!hati# draina$e of stoa#h

Ner%e su!!"y of the stoa#h:

'- Sy!atheti#:from celiac plexus around celiac trunk. It causes relaxation of

the wall and contraction of pyloric sphincter. It carries also pain sensation.(- Parasy!atheti#: from anterior and posterior gastric nerves. It is secretory to

the glands of the stomach, inhibitory to the pyloric sphincter and motor to the

wall.

The Sa"" Intestine The sa"" intestine& is a convoluted tube, about A meters long, extending from the

!y"orus to the i"eo'#e#a" %a"%e, situated centrally in the abdominal cavity and is

flanked laterally and superiorly by the large intestine.

Di%isions:

'. uodenum (. Oe%unum ). Ileum

The Duodenu

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' It is the shortest, widest and most fixed part of the small intestine.

Parts of the duodenu

Position and Sha!e:

ixed to the posterior abdominal wall #retroperitoneal$, occupies the epigastric

and umbilical regions.

ollows a C'shaped course around the head of the pancreas.

xtends from the pylorus to the duodeno-%e%unal flexure.

Parts of the duodenu:

)* First !art:

' - inches long, its 'stinch is mobile because it is covered by peritoneum

anteriorly and posteriorly.

'Itbe$insat the pylorus, '7( an inch to the right of the median plane at the level of

L) #transpyloric plane$.

Re"ations:

Anterior"y& ;uadrate lobe of the liver and gallbladder.

Posterior"y& neck of the pancreas, portal vein, bile duct, and gastro-duodenal

artery.

Inferior"y& head of pancreas.

Su!erior"y:related to epiploic foramen.

-* Se#ond !art:

) inches long and descends vertically from the level of +' to the level of +). This part

is only covered by peritoneum anteriorly.

Re"ations:

Anterior:right lobe of the liver, gall bladder, transverse colon and coils of

%e%unum.

Posterior: hilum of the right kidney.

Latera":hepatic flexure of the large intestine.

Media": head of pancreas, bile duct and pancreatico Nduodenal arteries.

+* Third !art&

* inch long, lies horizontally opposite to the level ofL+*

Re"ations&

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Anterior: superior mesenteric vessels in the root of the mesentery of the small

intestine and coils of small intestine.

Posterior: it is related to the following structures from the right to the left side&

right ureter, right psoas ma%or, right. gonadal vessels, I5, aorta and inferior

mesenteric artery. Su!erior& head of pancreas.

Inferior& coils of small intestine.

1* Fourth !art&

It is one inch long. It ascends from the level of the third to the level of the second

lumber vertebra one inch to the left of median plane at the dudeno-%e%unal flexure.

Re"ations:

Anterior: transverse colon and transverse mesocolon.

Re"ations of the duodenu

Posterior: left sympathetic chain, left psoas ma%or, left gonadal and left renal vessels.

Media": head of pancreas and aorta.

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They form the mobile part of the small intestine, suspended from the posterior

abdominal wall by a mesentery.

Differen#es bet3een 8e8unu and i"eu&

>e8unu I"eu

'. Len$th The proximal (7E The distal )7E

(. Diaeter 6ide 2arrow

+*Arteria" ar#ades ew and simple 2umerous and complex

1* Mesentery ew fat ,presents 3indo3s Much fat, no 3indo3s

4* Mu#osa" Cir#u"ar

Fo"ds

. P"i#a Cir#u"aris/

2umerous ew

?*Peyer&s Pat#hes no Nuerous Peyer@s !at#hes

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Mesentery of sa"" intestine

Mesentery of the sa"" intestine& is a fan- shaped peritoneal fold which has an

anterior free border and posterior attached border. The anterior border contains the

%e%unum and ileum and is A meter long. The posterior border is the root of mesentery

and is A inches long.

Borders:

)* Atta#hed border#root of mesentery$& It is Ainches, extends from duodeno-%e%unal

flexure to iliocecal %unction.

Stru#tures #rossed by the root of the esentery .6/:

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'. )rdpart of duodenum

(. 3bdominal aorta and right gonadal vessels.

). I5.

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Len$th:is about '.E meters.

Parts:

aecum and appendix.

olons #ascending,transverse,descending and pelvic$ lexures #right and left colic flexures$.

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Position: It occupies the right iliac fossa and is completelycoveredwith peritoneum.

Re"ations:

Anterior"y& anterior abdominal wall, greater omentum, and coils of small

intestine.

Posterior"y& - Muscles& !soas ma%or and iliacus.

( 2erves& emoral and lateral cutaneous nerve of the thigh.

Posterior re"ations of #ae#u

Couni#ations of the #ae#u:

Terina" i"eu:opens into the posteromedial aspect of the caecum at

i"eo#e#a" orifi#e& guarded by i"eo#e#a" %a"%e*

A!!endi,& opens into the posteromedial aspect, inferior to the ileocecal

opening*

As#endin$ #o"on: continuous upwards with it.

Interior of #e#u to sho3 i"eo#e#a" %a"%e

Peritonea" re#esses re"ated to the #e#u:

)* Su!erior I"eo#e#a" Re#ess:behind the vascular fold of the cecum.

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-* Inferior I"eo#e#a" Re#ess:behind the ileocecal fold.

+* Retro#e#a" Re#ess:behind the cecum.

Peritonea" re#esses re"ated to the #e#u

B"ood su!!"y of #ae#u:

Arteria" su!!"y: anterior and posterior #ae#a" arteries from i"eo#o"i# artery

which is a branch from superior mesenteric artery.

0enous draina$e:into superior mesenteric vein then into portal vein.

The 0erifor a!!endi,

It is a worm like tube, about 'F cm long, opens by its base into posteromedialaspect of the caecum below the terminal ileum. It has a mesentery known as

mesoappendix which is a triangular peritoneal fold, containing the appendicular artery

in its free border.

Positions of the A!!endi,:

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the posterior caecal artery from ileocolic artery.

0enous drain$e: into superior mesenteric vein.

Surfa#e anatoy of the Base of the a!!endi,

.M#Burney@s !oint/:

It is represented by a point at the %unction oflateral '7)

rdand medial (7)rdof a line connecting

anterior superior iliac spine and the umbilicus.

C"ini#a" note:inflammation of the appendix

#appendicitis$ causing ill-defined colicky pain, felt in the umbilical region whyQ

4ecause, the appendix is supplied with sympathetic fibers from 'F ththoracic spinal cord

segment, and the 'Fththoracic somatic nerve supplies the skin of umbilical region.

The As#endin$ #o"on

It begins as a continuation of the cecum and ends %ust below the "i%er& here it

continues with the transverse colon atthe ri$ht #o"i# .hepatic/ f"e,ure*It is covered

by peritoneum anteriorly and on each side.

Position and !eritonea" #o%erin$ of as#endin$ #o"on

Re"ations:

Posterior re"ations&

iliolumbar ligament, transverses abdominis, ;uadratus lumborum and iliacus.

) nerves& iliohypogastric, ilioinguinal and lateral cutaneous of the thigh.

' viscera& right kidney.

Anterior re"ations: oils of small intestine and greater omentum.

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Posterior re"ations of as#endin$ #o"on

B"ood su!!"y:

Arteria" su!!"y: rom superior mesenteric artery

'- Ileocolic artery (-

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Contents of trans%erse eso#o"on:

'. Transverse colon. (. Middle colic artery.

). xtra-peritoneal fat. *. sympathetic nerves.

B"ood su!!"y:Arteria" su!!"y:

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Peritonea" #o%erin$s: It is covered by peritoneum anteriorly and on each side.

N*B: left colic flexure is higher than the right flexure and attached to the diaphragm

by a peritoneal fold called !hreni#o'#o"i# "i$aent which prevents vertical descent

of the spleen into the left iliac fossa in case of splenomegaly.

The Pe"%i# .si$oid/ #o"on

It begins at the left side of the pelvic brim.

It ends at the )rdsacral piece where the rectum begins.

It describes 0-shaped course.

It is completely covered with peritoneum and suspended by the sigmoid

mesocolon.

Arteria" su!!"y of "ar$e intestine Inferior re"ations of !e"%i# #o"on

B"ood su!!"y:

Arteria" su!!"y: sigmoid branches of the inferior mesenteric artery.

0enous draina$e:It drains its venous blood into the veins corresponding to the

arterial supply.

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Si$oid eso'#o"on: is a peritoneal fold which is attached to the posterior pelvic

wall by an inverted 0'shaped root*

0igmoid meso-colon has an apex and two limbs.

The apex of the meso-colon lies anterior to the left ureter and the point ofbifurcation of the left common iliac artery.

Medial limb& descends infront of the sacrum and ends opposite the ) rdsacralpiece.

+ateral limb& extends along the left side of pelvic brim along the left externaliliac vessels.

Contents of the si$oid eso#o"on:

'. 0igmoid colon in the free border.

(. 0igmoid vessels in the lateral limb.

). 0uperior rectal vessels in the medial limb.

The Re#tu

Be$innin$:

Course:

Terination:

Be$insat the +rdsa#ra" !ie#eas a continuation of the

sigmoid colon.

Fo""o3sthe concavity of sacrumK coccyx #sa#ra" f"e,ure/*

Endsat the recto-anal %unction, about ) in#h in frontand

be"o3thetip of coccyx by bending posteriorly #!erinea"

f"e,ure/.

Its lower part is dilated and called a!u""a*

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Peritonea" #o%erin$ ;!!er )=+rdfront and sides are covered by peritoneum.

Midd"e )=+rdfront is only

covered by peritoneum.

Lo3er )=+rdhas No

peritoneal covering.

Latera" F"e,ures

Mu#osa" fo"ds

.valves$*

'. +ateral flexures&

a. /pper flexure& oncave to the left side. b. Middle flexure& oncave to the right side.

c. +ower flexure& oncave to the left side.

(. 3ntero-posterior flexures&

a. 0acral flexure&

- It is concave forwards #following the concavity of the

sacrum$.

b. !erineal flexure&

- It is convex forwards and lies at the recto-anal %unction.

- The lower end of the rectum is dilated and called the

?ampulla of the rectum@.

Re"ations of the re#tu:

In a"es: In fea"es

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'* Su!erior re#ta" artery&

- It is the continuation of inferior

esenteri# artery*

- It supplies the rectum and upper half

of anal canal.

(. Midd"e re#ta" artery& It arises from the anterior division of

internal iliac artery.

)* Inferior re#ta"artery&

It arises from internal pudendal artery.

)* Su!erior re#ta" %eincontinues up

as inferior esenteri# %ein 3hi#h

drains into the s!"eni# %ein*

.Porta" #ir#u"ation/

-* Midd"e re#ta" %ein:

rains into internal iliac vein..Systei# #ir#u"ation/

+* Inferior re#ta" %ein:

rains intointerna" !udenda" %ein*

.Systei# #ir#u"ation/

C"ini#a" note:

0uperior, middle, and inferior rectal

veins anastomose with each other in

submucosa of rectum and anal canal.

5eorrhoids .!i"es/: is the dilation

of the veins at the site of anastomosis*

Ly!h draina$e:

'- /pper half drains to para rectal +.2s which drain to inferior mesenteric +.2s.

(- +ower half drains to internal iliac lymph nodes.

The Ana" #ana"

Be$innin$: It be$ins one in#hbelow and anterior to the tip of the coccyx at the

recto-anal %unction*Course: It runsdown and backwards.

Terination: It ends at the anus.

Re"ations:

Latera""y:Ischioanal fossae.

Posterior"y:3nococcygeal raphe between it and tip of coccyx.

Anterior"y:!erineal body between it and bulb of penis in males.

!erineal body between it and vagina in females.

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&emorr#oids

'(iles)

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In fea"e In a"e

Anterior and !osterior re"ations of ana" #ana" .sa$itta" se#tion/

Latera" re"ations of ana" #ana" .#orona" se#tio

B"ood su!!"y& ner%e su!!"y and "y!h draina$e of ana" #ana":

/pper part +ower part

4lood

supply

-It is supplied by superior rectal

artery.

- It is drained by superior rectal vein

.!orta" #ir#u"ation$.

-It is supplied by&

'- Middle rectal artery of internal iliac artery.

(- Inferior rectal artery of internal pudendal

artery.

-The corresponding veins drain into internal

iliac vein #systei# #ir#u"ation.$

2erve

supply

3bove pectinate line by autonomic

nerve fibers.

4elow pectinate line by inferior rectal nerve

.Sensiti%e to !ain tou#h$.

+ymphaticdrainage

Abo%epectinate line into interna"i"ia# LNs.

Be"o3the pectinate line into su!erfi#ia"in$uina" LNs*

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Ana" s!hin#ters:

Interna" ana" s!hin#ter:

'It is the thickenedinner in%o"untary #ir#u"ar muscle layer of the anal canal.

-Surroundsthe upper +=1thof the anal canal, extending from ano-rectal %unction till

the white line #=iltonDs line$.

Ner%e su!!"y: autonomic

E,terna" ana" s!hin#ter:

'Striated %o"untary us#"e fibers*

'Surrounds the 3ho"e "en$th of the anal canaloutside the internal anal sphincter*

'Parts:

I/ Sub#utaneous Part&-0urrounds the anus %ust under the perianal skin.

-3ttached to perineal body Kanococcygeal raphe.

II/ Su!erfi#ia" Part:

'0urrounds the lower part of the internal sphincter above the subcutaneous part.

- It takes origin from anococcygeal body and last piece of coccyx.

III/ Dee! !art:

' It encircles the upper part of anal canal and no bony attachments.

7a"" of ana" #ana" sho3in$ ana" s!hin#ters

Ana" trian$"e:

1 It is the posterior division of the perineum that is bounded by&

- Tip of coccyx #post.$

- 0acrotuberous ligament on each side.

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- 3n imaginary line that connects the two ischialtuberosities #ant$.

Di%isions of the !erineu

Contents:

1 +ower part of anal canal in the middle.

1 Ischio-anal #Ischio-rectal$ fossa on each side.

The Is#hiore#ta" Fossa

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Contents and !osition of !udenda" #ana"

Arteria" su!!"y of the a"ientary #ana"

6hen the disposition of the peritoneum in the adult is clear, the course of the three

ventral branches of the aorta to the gut can be followed simply. They are distributed

subse;uently to the foregut, midgut, and foregut.

Arteria" su!!"y of the fore$ut

Coe"ia# trun(

- It is the artery of the foregut, and it divides into three branches which supply thealimentary canal down to the opening of bile duct, and liver, spleen and pancreas.

- It arises from the front of the aorta opposite the upper part of the body of the first

lumbar vertebra. It is a short wide trunk.

- The semilunar sympathetic #coeliac$ ganglia lie on each side of the artery and send

nerves to the artery which are carried along all its branches.

Coe"ia# trun( and its bran#hes

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- It appears at the upper border of the pancreas and divides immediately into its three

branches&

)' Left $astri# artery: It gives an oesophageal branch which runs up on the

oesophagus to supply the lower part of oesophagus. It then enters between the two

leaves of the lesser omentum and turns to the right along the lesser curvature. It breaksinto two parallel branches which anastomose with the two branches of the right gastric

artery.

Bran#hes of #e"ia# trun(

-' S!"eni# arteryarises at the upper border of the pancreas and passes to the left. It is

very tortuous. It runs above the pancreas then it turns forward in the lieno-renal

ligament to the hilum of the spleen. =ere it breaks up into four or five short

branches that radiate as they sink into the splenic substance.

Bran#hes:

'. Pan#reati#branches& They are the main source of arterial supply to the

pancreas. 0everal branches supply that gland one large branch is named the

arteria !an#reati#a a$na.

(. Left $astro'e!i!"oi# artery& It passes to the greater curvature of the stomach

between the leaves of lesser omentum.

). Short $astri# arteries:They are short arteries that pass to the fundus of the

stomach.

+' 5e!ati# arterypasses over the upper border of the pancreas, downwards and to

the right as far as the first part of the duodenum. It turns forward at the opening

into the lesser sac and curves upwards between the two layers of lesser omentum

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- The two vessels then pass over the third part of the duodenum and enter the upper

end of the mesentery of the small intestine. - They pass down to the right along the

root of the mesentery and end at the ileum ( feet proximal to the caecum.

Position and re"ations of su!erior esenteri# artery

Bran#hes :

'- Inferior !an#reati#o'duodena" artery:It supplies the duodenum below the

entrance of the bile duct. It runs in the curve between the duodenum and the head

of the pancreas and anastomoses with the superior pancreatico-duodenal artery.

(- >e8una" arteries: They arise from the left of the main trunk and pass forward

between the two layers of the mesentery. They %oin each other in a series of

anastomosing loops which form single arterial arcades in the upper part of the

%e%unum, double arcades down. rom the arcades straight arteries pass to the

mesenteric border of the %e%unum.

)- I"ea" arteries: They enter the mesentery and form a series of arterial arcades.

0traight vessels #vasa recta$ pass to the mesenteric border of the ileum. The arcades

of the terminal ileal branch anastomose with those of the terminal part of the main

trunk of the superior mesenteric artery.

*- I"eo'#o"i# artery:It arises from the right side of the superior mesenteric trunk low

down in the base of the mesentery. It runs to the ielo-colic %unction, where it gives

off&

a* I"ea" bran#h:It anastomoses with the terminal branch of the superior

mesenteric artery.

b* Co"i# bran#h:It runs up along the left side of the ascending colon to

anastomose with the right colic artery.#* Anterior #oe#a" artery:It ramifies over the anterior surface of the caecum.

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d* Posterior #oe#a" artery: It supplies the posterior wall of the caecum.

e* A!!endi#u"ar artery: It passes towards the tip of the appendix in the meso-

appendix.

E- Ri$ht #o"i# artery: It arises in the root of the mesentery from the right side of the

superior mesenteric artery. It runs to the right and divides near the left side of theascending colon into two branches.

a* The descending branch runs down to anastomose with the colic branch of the

ileo-colic artery. b* The ascending branch runs up to anastomose with a

branch of the middle colic artery.

A- Midd"e #o"i# arterypasses forwards between the two leaves of the transverse

mesocolon and at the intestinal border of the transverse mesocolon it divides into

right and left branches which run along the transverse colon. The right branch

anastomoses with the ascending branch of the right colic artery. The left branch

anastomoses with a branch of the left coli artery.

Arteria" su!!"y of the hind$ut

The inferior esenteri#which supplies the whole extent of the hindgut.

Inferior esenteri# artery

- It arises from the front of the aorta at the inferior border of the third part of the

duodenum opposite the third lumber vertebra. - It runs obli;uely down to the pelvic

brim. "ver the pelvic brim it continues along the pelvic wall in the root of the pelvicmesocolon as the su!erior re#ta" artery.

Bran#hes:

)' Left #o"i# artery& It passes up to the left towards the splenic flexure. It divides into

two branches. 3. The upper branch passes to splenic flexure. 4. The lower branch

passes transversely to the descending colon. ach of the arteries divides into

ascending and descending branches which anastomose with the left branch of the

middle colic artery and with each other.

-' Si$oid arteries: They are three or four branches which pass forwards between

the layers of the pelvic mesoclon, in which they form anastomosing loops from whichvessels sink into the wall of the pelvic colon.

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Arteria" su!!"y of id and hind $ut

The Porta" %enous syste

It is the system formed by the veins draining the :IT. These veins collect into the portal vein which breaks into the liver sinusoids.

Porta" %ein:

Ori$in:It is formed by union of the superior mesenteric and splenic veins behind

the neck of pancreas and in front of I5.

Course re"ations: It ascends behind the 'stpart of duodenum and in front of

I5, then in the free border of the lesser omentum with the hepatic artery

#left$ and bile duct #right$ anterior to it.

Porta" %ein and its tributaries

Tributaries:

'- 0uperior mesenteric vein.

(- 0plenic vein #It receives the inferior mesenteric vein$.

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)-

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*. 3nastomosis between the right colic vein #portal$ and the right renal vein

#systemic$.

#the same on the left side$

E. 3nastomosis between the bare area of the liver #portal$ and the phrenic veins

#systemic$.A. 3nastomosis between the superior mesenteric vein #portal$ and the I5 #systemic$

through the vein of

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Su!erior re"ations of the "i%er

*- Posterior surfa#e: It is formed of& bare area, groove for I5, caudate lobe #it has

two processes& the caudate process anteriorly to the right, and the papillary process

anteriorly to the left$, fissure for ligamentum venosum and oesophageal notch.

Bare area of "i%er: It is a triangular area related directly to the diaphragm #not

covered by peritoneum$, its base is formed by the groove for I5, its apex is formed

by right triangular ligament, its sides are the two layers of coronary ligament.

E- Inferior .0is#era"/ surfa#e& it shows the following features and impressions&

a. :astric impression, b. issure for ligamentum teres, c. Suadrate lobe, d. ossa forgall bladder, e. uodenal impression, f.

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It is a rectangular part of the inferior surface of liver. It is bounded by&

- inferior border of liver #inf$.

- porta hepatis #post$

- gall bladder fossa #on the right$

- fissure for ligam. teres #on left side$B It is related to& transverse colon #ant$, pylorusK

'st part of duodenum #middle$ and lesser

omentum #post$.

Caudate "obe:

It is related on the right side to groove for the

I5, "n the left side to fissure for the

ligamentum venosum superior to ligamentum

venosum as it curves to %oin the I5. and

inferior to porta hepatis.

The lower and right part of the caudate lobe

forms a pro%ection called the caudate

process which forms the superior boundary of

the epiploic foramen.

The lower and left part of the caudate lobe forms a pro%ection called the papillary

proces

module 17 git

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