Abdomen Wall

The abdomen is the part of the trunk that lies between the thorax
and the pelvis.

The abdominal cavity is located between the thoracic diaphragm and
the pelvic rim (linea terminalis)

The diaphragm forms the roof of the abdominal cavity.

The cavity is continuous with the pelvic cavity; therefore it has no
floor.

******The abdominal cavity extends superiorly into the osteocartilaginous
thoracic cage to about the 5th intercostal space in the supine position;
consequently, parts of the liver, stomach, and spleen are protected by
the thoracic cage.

The abdominal wall extends from the osteocartilagenous thoracic cage to the pelvis

Anterior Abdominal Wall
-Superiorly by the right and left costal margins.
-Inferiorly by a line connecting each ASIS to the pubis.
-Laterally by a vertical line through ASIS.

Umbilicus: L3-L4
intervertebral disc

Line Alba: median fibrous
white line divides the
abdomen into right and
left sides. Indicated by a
vertical groove from the
xiphoid process to the
pubis

*****Linea Semilunaris: curved
line or groove (convex
laterally). It extends from
the 9th costal cartilage to
the pubis. It is located 5-8
cm from the median plane.
Represents the lateral
border of the rectus
abdominis muscle

Tendinous Intersections:
transverse lines over the
rectus abdominis muscle

Inguinal Groove: division
between the anterior
abdominal wall and
anterior thigh region

******Pubic Symphysis: firm
resistance felt at the inferior
end of the linea alba at the
anterior aspect of the
median plane

Pubic crest and tubercle:
bony landmark located 2.5
cm laterally of the pubic
symphysis. The inguinal
ligament attaches there

The abdomen is the part of the trunk that lies between the thorax
and the pelvis.

Epigastric Fossa: slight
depression in the
epigastric region just
inferior to the xiphoid
process. Particularly
noticeable in the supine
position

*****Subcostal Plane: joins the inferior margins of the 10th costal
cartilage passing through L2-L3.

*****Transtubercular Plane (TTP): through the iliac tubercles.
Usually passes through the body of L5.

*****Transpyloric Plane (TPP): This plane is usually midway
between the xiphosternal joint and the umbilicus. It passes
through the inferior borders of L1. Key plane: many abdominal
viscera related to it.

*****Transumbilical Plane (TUP): through the umbilicus. Indicates
the level of intervertebral disc between L3-L4.

TRANSPYLORIC PLANE (L1)

SUBCOSTAL PLANE (10TH costal cartilage-L2/L3)

TRANSUMBILICAL PLANE (L3-L4)

INTERTUBERCULAR PLANE (L5)

The fascia of the anterior abdominal wall is broken into superifical and deep

The fatty superifical fascia is called camper's fascia and the membranous deep superifical fascia is called scarpa's fasica . There is also a deep fasica that covers the superifical muscles.

- aponeuroses of all three
muscles form the anterior wall
of the rectus sheath.
-FASCIA TRANSVERSALIS

The membranous deep layer is also continuous with the superficial
fascia of the perineum or Colle’s fascia, and with that investing the
scrotum, penis, and the labia majora

********SUPERFICIAL VESSELS IN THE SUPERFICIAL FASCIA
(Superficial Epigastric arteries [femoral artery] and veins)

1. External oblique
2. Internal oblique
3. Tranversus Abdominis
4. Rectus abdominis

N: Inferior 6 thoracic nerve + subcostal nerve
A: Compress and support abdominal viscera, flex/ rotate the trunk

-The fibers of the external oblique muscle run inferoanteriorly and medially.
-As the fibers pass medially, they become aponeurotic. This aponeurosis ends in the linea alba.

Inferiorly, the aponeurosis of the EOM folds back on itself to form the
INGUINAL LIGAMENT (Poupart’s Ligament) which extends from the
ASIS to the pubic tubercle.

N: Inferior 6 thoracic nerve
A: Compress and support the abdominal visera, flex and rotate the trunk

*****• In the male the spermatic cord passes through the internal oblique
muscle fibers from which the cremasteric muscle is formed.
• The inguinal canal passes through it and, it is formed in part by the
IOM.

N: Inferior 6 thoracic nerves
AL Compress and support abdominal visera

Insertion of IOM and
transversus abdominis onto the pubic symphysis

N: Inferior six thoracic nerves
A: Flexes the trunk and compresses the abdominal viscera

The rectus sheath is formed by the aponeurosis of the EOM, IOM
and transversus abdominis as they insert into the
linea alba.

The internal oblique muscle aponeurosis splits into two
layers, with the anterior portion
going ABOVE the rectus
abdominis, and the posterior
part going BELOW the rectus.

The upper 2/3 of the rectus sheath is made by the EOM aponeursis, the IOM aponeurosis, and the transversus abdominis

Superior to the acurate line the rectus sheath goes external oblique, internal oblique *SPLITS*, ***rectus abdominus, internal oblique again *SPLITS*and then transversus abdominis

Inferior to the acurate line, the rectus sheath goes external oblique, internal oblique, transversus abdominis, **** rectus abdominus, and then transversalis fascia

The lower 1/3 of the rectus sheath is formed by the aponeurosis of all three muscles of anterior wall and the fascia transversalis (posterior)

UPPER 2/3 OF RECTUS
SHEATH:
Between ASIS and Costal
margins

LOWER 1/3 OF RECTUS
SHEATH:
Between ASIS and Pubic
symphysis

The inferior limit of the posterior wall of the rectus sheath is marked
by a crescentic border called the ARCUATE LINE which is located
midway between the umbilicus and the pubis.

The internal spermatic fascia of the spermatic cord is derived from the fascia transversalis

• Skin
• Superficial fascia: Camper’s
• Scarpa’s
• Deep fascia
• EOM and aponeurosis
• IOM and aponeurosis
• Transversus Abdominis
• Fascia transversalis
• Extraperitoneal fat
• Peritoneum: • Parietal • Peritoneal cavity • Visceral • Abdominal viscera

T7-T11

T12

T12

L1

L1

*****Iliohypogastric nerve (L1) = skin over upper inguinal
region (groin), skin over iliac crest.

******lioinguinal nerve (L1) = skin over the superomedial
aspect of the thigh. Also, the skin of the lower inguinal
region, mons pubis, anterior scrotum, or labia majora.

Superior epigastric artery (Internal thoracic)

Inferior epigastric artery (External iliac artery)

Lumbar arteries (abdominal aorta)

Deep circumflex iliac (External iliac artery)

Superficial epigastric artery (femoral artery)

The inferior epigastric artery runs superiorly on the
transversalis fascia and enters the arcuate line to gain
the rectus sheath.

********The superior epigastric artery enters the rectus sheath
superiorly just inferior to the 7th costal cartilage.

Superior to the umbilicus

Large median fold =
FALCIFORM
LIGAMENT which goes
to the liver and
diaphragm. Its free edge
is the LIGAMENTUM
TERES containing the
remnant of the umbilical
vein (obliterated)

Inferior to the Umbilicus:
– Median Umbilical Fold =
urachus
– Medial Umbilical Fold =
obliterated umbilical
artery
– Lateral Umbilical Fold =
inferior epigastric artery