AnatomAnatom

yy of of AnterioAnterio

r r AbdomiAbdominal Wallnal Wall

Mohammed El-MataryLecturer of General SurgeryLecturer of General Surgery

Ain Shams UniversityAin Shams University

Anterior Anterior Abdominal WallAbdominal Wall

• Layer of anterior abdominal wall:Layer of anterior abdominal wall: A- Lateral:A- Lateral: 1- Skin. 2- Subcutaneous tissue. 3- External oblique muscle. 4- Internal oblique muscle. 5- Transversus abdominis muscle. 6- Fascia transversalis. 7- Peritoneum.

Anterior Anterior Abdominal WallAbdominal Wall

B- Medial:B- Medial: 1- Skin.1- Skin.

2- Superficial fascia.2- Superficial fascia.

3- Anterior wall of rectus sheath.3- Anterior wall of rectus sheath.

4- Rectus muscle.4- Rectus muscle.

5- Posterior wall of rectus sheath.5- Posterior wall of rectus sheath.

6- Peritoneum.6- Peritoneum.

1 -Skin

A- Lateral

2 -Subcutaneous tissue

A- Lateral

3 -External Oblique m.

A- Lateral

4 -Internal Oblique m.

A- Lateral

5 -Transversus abdominis m.

A- Lateral

6- Fascia Transversalis m

A- Lateral

7- Peritoneum

A- Lateral

Anterior Anterior Abdominal WallAbdominal Wall

• Layer of anterior abdominal wall:Layer of anterior abdominal wall:

B- Medial:B- Medial: 1- Skin.1- Skin.

2- Superficial fascia.2- Superficial fascia.

3- Anterior wall of rectus sheath.3- Anterior wall of rectus sheath.

4- Rectus muscle.4- Rectus muscle.

5- Posterior wall of rectus sheath.5- Posterior wall of rectus sheath.

6- Peritoneum.6- Peritoneum.

1 -Skin

B- Medial

2 -Subcutaneous tissue

B- Medial

3 -Ant. Wall of Rectus sheath

B- Medial

4 -Rectus Muscle

B- Medial

B- Medial

5 -Post. Wall of Rectus sheath

B- Medial

6 -Peritoneum

External Oblique MuscleExternal Oblique Muscle

OriginOrigin

Fleshy digitations from the lower 8 ribs

External Oblique MuscleExternal Oblique Muscle

The muscle is inserted by fleshy fibers as well as aponeurosis, as follows:

A- Fleshy fibers:Outer lip of the iliac crest

B- Aponeurosis:1. Medial part → linea alba from xiphoid process to

symphysis pubis

2. Lateral part → folded upwards & backwards upon itself to form the inguinal ligament (ASIS → pubic tubercle)

InsertionInsertionXiphoid

Process

Symphysis Pubis

External Oblique MuscleExternal Oblique Muscle

Direction of fibersDirection of fibers

DownwardDownward

Forwards Forwards

MediallyMedially

External Oblique MuscleExternal Oblique Muscle

Nerve SupplyNerve Supply

Intercostal nerves (TIntercostal nerves (T7 7 -T-T1111) & ) &

Subcostal nerve (TSubcostal nerve (T1212))

Internal Oblique MuscleInternal Oblique Muscle

OrigiOriginn

InsertionInsertion

1. Anterior 2/3 of the intermediate line of the iliac crest2. The lateral 2/3 of the inguinal ligament3. Lumbar fascia

1. Lower 6 costal cartilages 2. Xiphoid process 3. Linea Alba 4. Pubic crest

Internal Oblique MuscleInternal Oblique MuscleDirection of fibersDirection of fibers

UpwardsUpwards

Forwards Forwards

MediallyMedially

Nerve SupplyNerve SupplyTT77-T-T1212

Iliohypogastric n. Iliohypogastric n.

Ilioinguinal n.Ilioinguinal n.

Transversus Abdominis MuscleTransversus Abdominis MuscleOriginOrigin

1- Lower 6 intercostal cartilages1- Lower 6 intercostal cartilages

2- Lumbar Fascia2- Lumbar Fascia

3- Ant. 2/3 of inner lip of iliac crest3- Ant. 2/3 of inner lip of iliac crest

4- Lat. 1/3 of inguinal ligament4- Lat. 1/3 of inguinal ligament

Transversus Abdominis MuscleTransversus Abdominis MuscleInsertionInsertion

1- Xiphoid Process1- Xiphoid Process

2- Pubic Crest2- Pubic Crest

3- Linea Alba3- Linea Alba

Direction of Direction of fibersfibers

Transversus Abdominis MuscleTransversus Abdominis Muscle

HorizontallyHorizontally

Nerve SupplyNerve Supply

Transversus Abdominis MuscleTransversus Abdominis Muscle

TT77-T-T1212

Iliohypogastric n. Iliohypogastric n.

Ilioinguinal n.Ilioinguinal n.

Rectus Abdominis Rectus Abdominis MuscleMuscle

OriginOrigin

From the pubic crestFrom the pubic crest

InsertionInsertion

7th, 6th, 5th costal cartilages7th, 6th, 5th costal cartilages

Xiphoid processXiphoid process

Rectus Abdominis Rectus Abdominis MuscleMuscle

The muscle is divided into segments The muscle is divided into segments by tendinous intersections, Which by tendinous intersections, Which indicate that the muscle arises from a indicate that the muscle arises from a number of myotomes, fused togethernumber of myotomes, fused together

1- Segmental nerve supply.1- Segmental nerve supply.

2- Hematoma of rectus m. is localized2- Hematoma of rectus m. is localized

2- In paramedian incision 2- In paramedian incision displace m. displace m.

laterally (n. supply comes from lateral)laterally (n. supply comes from lateral)

Surgical ImportanceSurgical Importance

Pyramidalis Pyramidalis MuscleMuscle

It is a landmark of linea It is a landmark of linea alba intraoperativealba intraoperative

Actions of Anterior Abdominal Actions of Anterior Abdominal Wall MusclesWall Muscles

• They assist in raising the intra-bdominal pressure (so, They assist in raising the intra-bdominal pressure (so, they help in vomiting, cough, delivery, etc….)they help in vomiting, cough, delivery, etc….)

• Keep the abdominal viscera in position.Keep the abdominal viscera in position.• Rectus abdominis flexes the trunk, while the 2 oblique Rectus abdominis flexes the trunk, while the 2 oblique

muscles bend the trunk laterally.muscles bend the trunk laterally.• Act as accessory expiratory muscles.Act as accessory expiratory muscles.• Lower midline & paramedian incisions.Lower midline & paramedian incisions.

MediallyMedially

LaterallyLaterally

Rectus SheathRectus Sheath

Linea AlbaLinea Alba

Linea SemilunarisLinea Semilunaris

Arcuate LineArcuate Line

Rectus SheathRectus Sheath

Falciform LigamentFalciform Ligament

External ObliqueExternal Oblique

Internal ObliqueInternal Oblique

Transversus AbdominisTransversus Abdominis

Ant. Layer of Rectus SheathAnt. Layer of Rectus Sheath

Post. Layer of Rectus SheathPost. Layer of Rectus Sheath

Rectus Abdominis Rectus Abdominis

Above Arcuate LineAbove Arcuate Line

SKINSKIN

PeritoneumPeritoneumTransverslais FasciaTransverslais Fascia

Rectus SheathRectus SheathExternal ObliqueExternal Oblique

Internal ObliqueInternal Oblique

Transversus AbdominisTransversus Abdominis

Ant. Layer of Rectus SheathAnt. Layer of Rectus Sheath

Rectus Abdominis Rectus Abdominis

Below Arcuate LineBelow Arcuate Line

Urachus in Median Umbilical FoldUrachus in Median Umbilical Fold

Medial Umbilical Ligament Medial Umbilical Ligament

Transverslais FasciaTransverslais Fascia

SKINSKIN

PeritoneumPeritoneum

Superior epigastric a.Superior epigastric a.

Subcostal a.Subcostal a.

Inferior epigastric a.Inferior epigastric a.

Deep circumflex iliac a.Deep circumflex iliac a.

- I -- I -Internal Mammary a.Internal Mammary a.

- III -- III -External Iliac a.External Iliac a.

- II - - II - Descending AortaDescending Aorta

1010thth, 11, 11thth intercostal a. intercostal a.