1. Abdominal regions. 2. Walls of abdomen. 3. Muscles of abdomen: classification. 4. Superficial and internal inguinal rings. Abdominal press. 5. Fasciae of abdomen. 6. Weak points of walls of abdomen.

1. The Department of Human anatomyThe Department of Human anatomy
The abdomen.The abdomen.
Regions, muscles,Regions, muscles,
weak points of walls ofweak points of walls of
abdomenabdomen

2. PLANPLAN
 Abdominal regions.Abdominal regions.
 Walls of abdomen.Walls of abdomen.
 Muscles of abdomen: classification.Muscles of abdomen: classification.
 Superficial and internal inguinalSuperficial and internal inguinal
rings. Abdominal press.rings. Abdominal press.
 Fasciae of abdomen.Fasciae of abdomen.
 Weak points of walls of abdomen.Weak points of walls of abdomen.

3. Abdomen is theAbdomen is the
region of bodyregion of body
lying betweenlying between
the diaphragmthe diaphragm
above and pelvisabove and pelvis
below. It containsbelow. It contains
the contents ofthe contents of
digestive anddigestive and
urinary systems.urinary systems.

4.  Two horizontal andTwo horizontal and
two vertical linestwo vertical lines
divide the abdomendivide the abdomen
into nine "regions."into nine "regions."

5. I. Epigastrium:I. Epigastrium:
1 (regio epigastrica)1 (regio epigastrica)
2. (regio hypocondrica dexter)2. (regio hypocondrica dexter)
3. (regio hypochondrica sinistra)3. (regio hypochondrica sinistra)
ІІ. Mesogastrium:ІІ. Mesogastrium:
4. (regio umbilicalis)4. (regio umbilicalis)
5. (regio lateralis dextra)5. (regio lateralis dextra)
6. (regio lateralis sinistra)6. (regio lateralis sinistra)
ІІІ. Hypogastrium:ІІІ. Hypogastrium:
7. (regio pubica)7. (regio pubica)
8. (regio inguinalis dextra)8. (regio inguinalis dextra)
9. (regio inguinalis sinister)9. (regio inguinalis sinister)
("hypo" means "below" and "epi" means("hypo" means "below" and "epi" means
"above", "chond" means "cartilage""above", "chond" means "cartilage"
(in this case, the cartilage of the rib)(in this case, the cartilage of the rib)
and "gast" means stomach).and "gast" means stomach).

6. Walls of abdomen:Walls of abdomen:
 Superior Wall:Superior Wall: The superior wall of abdomen is formed by theThe superior wall of abdomen is formed by the
diaphragm. It is a strong muscular sheath that has a vital role indiaphragm. It is a strong muscular sheath that has a vital role in
respiratory system.respiratory system.
 Inferior Wall:Inferior Wall: the conditional line to the entry of the pelvicthe conditional line to the entry of the pelvic
cavity.cavity.
 Anterior Wall:Anterior Wall: The anterior wall of abdomen is formed above byThe anterior wall of abdomen is formed above by
the lower part of thoracic cage. Below it is formed by Rectusthe lower part of thoracic cage. Below it is formed by Rectus
abdominis, External oblique, Internal oblique and Transversusabdominis, External oblique, Internal oblique and Transversus
abdominis muscles along with their fasciae.abdominis muscles along with their fasciae.
 Posterior Wall:Posterior Wall: The posterior wall of abdomen is formed in theThe posterior wall of abdomen is formed in the
midline by the five lumbar vertebrae and their intervertebralmidline by the five lumbar vertebrae and their intervertebral
discs. Laterally, it is formed by the twelfth rib, psoas muscle,discs. Laterally, it is formed by the twelfth rib, psoas muscle,
quadratus lumborum muscle and the border of bony pelvis. Thequadratus lumborum muscle and the border of bony pelvis. The
aponeurosis of origin of transversus abdominis muscle is alsoaponeurosis of origin of transversus abdominis muscle is also
involved in the formation of posterior wall of the abdomen.involved in the formation of posterior wall of the abdomen.

7. The layers of the abdominal wall are (fromThe layers of the abdominal wall are (from
superficial to deep):superficial to deep):
 SkinSkin
 FasciaFascia
 Camper's fascia - fatty superficial layer.Camper's fascia - fatty superficial layer.
 Scarpa's fascia - deep fibrous layer.Scarpa's fascia - deep fibrous layer.
 MuscleMuscle
 Rectus abdominisRectus abdominis
 External oblique muscleExternal oblique muscle
 Internal oblique muscleInternal oblique muscle
 Transverse abdominal muscleTransverse abdominal muscle
 Fascia transversalisFascia transversalis
 PeritoneumPeritoneum

8. Abdominal muscles
The muscles
of anterior wall
The muscles
of posterior wall
The muscles
of laterar wall
Pyramidalis
Obliquus externus
abdominis
Rectus Abdominus
Obliquus internus
abdominis
Transversus abdominis
Quadratus lumborum

9. The muscles
of anterior wall
Rectus Abdominus
Origin
5, 6, 7 costal cartilages,5, 6, 7 costal cartilages,
xiphoid processxiphoid process
InsertionInsertion
Pubic crest and pubic
symphysis
ActionAction
 Flexes trunk, aids forcedFlexes trunk, aids forced
expiration and raise intra-expiration and raise intra-
abdominal pressureabdominal pressure

10. Pyramidalis
Origin
 Pubic crest
Insertion
 Lower linea alba
ActionAction
 Is a tensor of the lineaIs a tensor of the linea
albaalba
 Reinforces lower rectusReinforces lower rectus
sheathsheath

11. The muscles of lateral wall
Obliquus externus Abdominis
Origin
 Anterior angles of lower eight
ribs
InsertionInsertion
 Outer anterior half of iliac crest,Outer anterior half of iliac crest,
inguinal lig, pubic tubercle andinguinal lig, pubic tubercle and
crest, and aponeurosis ofcrest, and aponeurosis of
anterior rectus sheathanterior rectus sheath
Action
 Supports abdominal wall,
assists forced expiration, aids
raising intraabdominal pressure
and, with muscles of opposite
side, abducts and rotates trunk

12. Obliquus internus
abdominis
Origin
 Lumbar fascia, ant. two thirds
of iliac crest and lateral two
thirds of inguinal ligament
InsertionInsertion
 Costal margin, aponeurosis ofCostal margin, aponeurosis of
rectus sheath (ant. and post. ),rectus sheath (ant. and post. ),
conjoint tendon to pubic crestconjoint tendon to pubic crest
and pectineal lineand pectineal line
ActionAction
 Supports abdominal wall,Supports abdominal wall,
assists forced respiration, aidsassists forced respiration, aids
raising intraabdominal pressureraising intraabdominal pressure
& , with muscles of other side ,& , with muscles of other side ,
abducts and rotates trunk.abducts and rotates trunk.
Conjoint tendon supportsConjoint tendon supports
posterior wall of inguinal canalposterior wall of inguinal canal

13. Transversus abdominis
Origin
 Costal margin , lumbar fascia,
ant two thirds of iliac crest and
lateral half of inguinal ligament
InsertionInsertion
 Aponeurosis of posterior andAponeurosis of posterior and
anterior rectus sheath andanterior rectus sheath and
conjoint tendon to pubic crestconjoint tendon to pubic crest
and pectineal lineand pectineal line
ActionAction
 Supports abdominal wall, aidsSupports abdominal wall, aids
forced expiration and raisingforced expiration and raising
intraabdominal pressure.intraabdominal pressure.
Conjoint tendon supportsConjoint tendon supports
posterior wall of inguinal canalposterior wall of inguinal canal

14. The muscles of posterior
wall
Quadratus lumborum
Origin
 Inferior border of 12th rib
Insertion
 Transverse processes of
L1-4, iliolumbar ligament
and post. 1/3 of iliac crest
ActionAction
 Fixes 12th rib duringFixes 12th rib during
respiration and lateralrespiration and lateral
Flexes of trunkFlexes of trunk

15. Rectus sheath above and below the umbilical chordRectus sheath above and below the umbilical chord
 1 – (m. rectus abdominis);1 – (m. rectus abdominis);
 2 – (m. obliguus externus abdominis);2 – (m. obliguus externus abdominis);
 3 – (m. obliguus internus abdominis);3 – (m. obliguus internus abdominis);
 4 – (m. transversus abdominis);4 – (m. transversus abdominis);
 а) (aponeurosis m. obliguus externus abdominis);а) (aponeurosis m. obliguus externus abdominis);
 b) (lamina anterior m. obliguus internus abdominis);b) (lamina anterior m. obliguus internus abdominis);
 c) (lamina posterior m. obliguus internus abdominis);c) (lamina posterior m. obliguus internus abdominis);
 d) (aponeurosis m. transverses abdominis);d) (aponeurosis m. transverses abdominis);
 e) (fascia transversalis).e) (fascia transversalis).

16.  weak points of walls of abdomenweak points of walls of abdomen
1) canalis inquinalis1) canalis inquinalis
2) linea alba2) linea alba
3) anulus umbilicalis3) anulus umbilicalis
4) trigonum lumbale Petiti4) trigonum lumbale Petiti
5) spatium tendinosum lumbale5) spatium tendinosum lumbale
6) trigonum hypochondriacum6) trigonum hypochondriacum
7) linea semilunaris Spigelii7) linea semilunaris Spigelii
8) trigonum sternocostale dext. et sin.8) trigonum sternocostale dext. et sin.
trigonum costolumbalis dext. et sin.trigonum costolumbalis dext. et sin.
9) canalis obturatorius9) canalis obturatorius
10) Foramen supra- et infrapiriformis10) Foramen supra- et infrapiriformis
11) canalis femoralis11) canalis femoralis

18.  Inguinal canal is an obliqueInguinal canal is an oblique
passage through the lower partpassage through the lower part
of anterior abdominal wall. It isof anterior abdominal wall. It is
present in both males andpresent in both males and
females.females.

19. Functions of inguinal canal:Functions of inguinal canal:
 In males, the inguinal canal allows structures ofIn males, the inguinal canal allows structures of
the spermatic cord to pass to and from the testisthe spermatic cord to pass to and from the testis
to the abdomen. This allows the testes to leaveto the abdomen. This allows the testes to leave
the abdominal cavity. The importance of thisthe abdominal cavity. The importance of this
phenomenon can be appreciated by remindingphenomenon can be appreciated by reminding
the fact that spermatogenesis takes place only ifthe fact that spermatogenesis takes place only if
the testes leave the abdominal cavity to go to athe testes leave the abdominal cavity to go to a
cooler environment in the scrotum.cooler environment in the scrotum.
 In the females, the inguinal canal is smaller asIn the females, the inguinal canal is smaller as
compared to males. It transmits the roundcompared to males. It transmits the round
ligament of uterus to pass from the uterus toligament of uterus to pass from the uterus to
labium majus.labium majus.
 In both males and females, the inguinal canal alsoIn both males and females, the inguinal canal also
transmits the ilioinguinal nerve.transmits the ilioinguinal nerve.

20. Structure of inguinal canal:Structure of inguinal canal:
 Inguinal canal is about 4-5 cm long in adults. ItInguinal canal is about 4-5 cm long in adults. It
extends fromextends from deepdeep inguinal ringinguinal ring, downward and, downward and
medially, to themedially, to the superficial inguinal ringsuperficial inguinal ring. The deep. The deep
inguinal ring is an oval opening in fasciainguinal ring is an oval opening in fascia
transversalis, while the superficial inguinal ring is atransversalis, while the superficial inguinal ring is a
triangular defect in the aponeuorsis of externaltriangular defect in the aponeuorsis of external
oblique muscle.oblique muscle.
 The inguinal canal lies immediately above andThe inguinal canal lies immediately above and
parallel to the inguinal ligament. However, inparallel to the inguinal ligament. However, in
infants, the deep inguinal ring lies almost posteriorinfants, the deep inguinal ring lies almost posterior
to the superficial, so that the canal is shorter. As ato the superficial, so that the canal is shorter. As a
result of growth in following years, the deepresult of growth in following years, the deep
inguinal ring moves laterally and the canalinguinal ring moves laterally and the canal
elongates.elongates.

21.  Walls of inguinal canal:Walls of inguinal canal:

22.  Anterior wall:Anterior wall: TheThe
anterior wall is formedanterior wall is formed
along its entire lengthalong its entire length
by the aponeuorsis ofby the aponeuorsis of
external obliqueexternal oblique
muscle. In its lateralmuscle. In its lateral
part, it is reinforced bypart, it is reinforced by
the origin of internalthe origin of internal
oblique from theoblique from the
inguinal ligament.inguinal ligament.

23.  Posterior wall:Posterior wall: TheThe
posterior wall of inguinalposterior wall of inguinal
canal is formed along itscanal is formed along its
entire length by theentire length by the
fascia transversalis.fascia transversalis.

24.  Floor of inguinal canalFloor of inguinal canal
(inferior wall):(inferior wall): The floor ofThe floor of
the canal is formed by thethe canal is formed by the
inguinal ligament. Thisinguinal ligament. This
ligament is in fact the rolled-ligament is in fact the rolled-
under inferior edge ofunder inferior edge of
aponeuorsis of externalaponeuorsis of external
oblique muscle. The medialoblique muscle. The medial
part of this wall is formed bypart of this wall is formed by
the lacunar ligament.the lacunar ligament.
 Roof of inguinal canalRoof of inguinal canal
(superior wall):(superior wall): The roof ofThe roof of
the canal is formed by thethe canal is formed by the
lowest fibers of internallowest fibers of internal
oblique and transversusoblique and transversus
abdominis muscles.abdominis muscles.

25.  Internal surface of anterior abdominalInternal surface of anterior abdominal
wallwall

27.  Inguinal canal as a potential weakness inInguinal canal as a potential weakness in
abdominal wall:abdominal wall:
 The presence of inguinal canal in lower partThe presence of inguinal canal in lower part
of anterior abdominal wall presents aof anterior abdominal wall presents a
potential weakness the structure of the wall.potential weakness the structure of the wall.
 The canal is oblique in its form. This causesThe canal is oblique in its form. This causes
the weaker parts of it to lie at some distancethe weaker parts of it to lie at some distance
apart, thus reducing chances of any type ofapart, thus reducing chances of any type of
damage.damage.

28.  The weak inguinal canal can be exploitedThe weak inguinal canal can be exploited
during forceful activities like coughing,during forceful activities like coughing,
sneezing, straining, parturition, defecationsneezing, straining, parturition, defecation
etc. To prevent this, the arching lowestetc. To prevent this, the arching lowest
fibers of internal oblique and transversusfibers of internal oblique and transversus
abdominis muscles contract and flatten outabdominis muscles contract and flatten out
the arched roof so that it is loweredthe arched roof so that it is lowered
towards the floor. In this condition, thetowards the floor. In this condition, the
canal is virtually closed.canal is virtually closed.

29. AnAn inguinal herniainguinal hernia
is a protrusionis a protrusion
of abdominal-of abdominal-
cavity contentscavity contents
through the inguinalthrough the inguinal
canal. They are verycanal. They are very
common (lifetimecommon (lifetime
risk 27% for men,risk 27% for men,
3% for women), and3% for women), and
their repair is one oftheir repair is one of
the most frequentlythe most frequently
performed surgicalperformed surgical
operations.operations.

30.  There are two types ofThere are two types of
inguinal hernia,inguinal hernia, directdirect andand indirectindirect, which are, which are
defined by their relationship to the inferiordefined by their relationship to the inferior
epigastric vessels. Direct inguinal hernias occurepigastric vessels. Direct inguinal hernias occur
medial to the inferior epigastric vessels whenmedial to the inferior epigastric vessels when
abdominal contents herniate through a weak spotabdominal contents herniate through a weak spot
in the fascia of the posterior wall of the inguinalin the fascia of the posterior wall of the inguinal
canal, which is formed by the transversalis fascia.canal, which is formed by the transversalis fascia.
Indirect inguinal hernias occur when abdominalIndirect inguinal hernias occur when abdominal
contents protrude through the deep inguinal ring,contents protrude through the deep inguinal ring,
lateral to the inferior epigastric vessels; this maylateral to the inferior epigastric vessels; this may
be caused by failure of embryonic closure ofbe caused by failure of embryonic closure of
the processus vaginalis.the processus vaginalis.

31.  Inguinal hernias, in turn, belongInguinal hernias, in turn, belong
to groin hernias, which alsoto groin hernias, which also
includes femoral hernias. A femoral herniaincludes femoral hernias. A femoral hernia
is not via the inguinal canal, but via theis not via the inguinal canal, but via the
femoral canal, which normally allowsfemoral canal, which normally allows
passage of the common femoral artery andpassage of the common femoral artery and
vein from the pelvis to the leg.vein from the pelvis to the leg.
 In Amyand's hernia, the content of theIn Amyand's hernia, the content of the
hernial sac is the vermiform appendix.hernial sac is the vermiform appendix.
 In Littre's hernia, the content of the hernialIn Littre's hernia, the content of the hernial
sac contains a Meckel's Diverticulum.sac contains a Meckel's Diverticulum.

32. Thank you for attention!Thank you for attention!