Atlas of Anatomy

12 Spaces

Divisions of the Abdominopelvic Cavity

Fig. 12.1   Organ layers and quadrants
Anterior view. The organs of the abdomen and pelvis can be classified by layer, by quadrant (using the umbilicus at L4), by level (upper and lower abdomen, and pelvis), or with respect to the presence of a mesentery (Table 12.1).

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Fig. 12.2   Peritoneum and mesentery

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Fig. 12.3   Peritoneal relationships
Midsagittal section through male pelvis, viewed from the left side.

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image Clinical

Acute abdominal pain

Acute abdominal pain (“acute abdomen”) may be so severe that the abdominal wall becomes extremely sensitive to touch (“guarding”) and the intestines stop functioning. Causes include organ inflammation such as appendicitis, perforation due to a gastric ulcer (see p. 159), or organ blockage by a stone, tumor, etc. In women, gynecological processes or ectopic pregnancies may produce severe abdominal pain.

Peritoneal Cavity & Greater Sac

image The largest part of the peritoneal cavity is the greater sac. The greater omentum is an apron-like fold of peri toneum suspended from the greater curvature of the stomach and covering the anterior surface of the transverse colon. The transverse colon divides the peritoneal cavity into a supracolic compartment (liver, gallbladder, and stomach) and an infracolic compartment (intestines).

Fig. 12.4   Dissection of the peritoneal cavity
Anterior view.

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Lesser Sac

Fig. 12.5   Lesser sac (Omental bursa)
Anterior view. The lesser sac (omental bursa) is the portion of the peritoneal cavity located behind the lesser omentum and stomach.

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Fig. 12.6   Location of the lesser sac

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Table 12.2 Boundaries of the lesser sac (omental bursa)

Direction

Boundary

Recess

Anterior

Lesser omentum, gastrocolic ligament

Inferior

Transverse mesocolon

Inferior recess

Superior

Liver (with caudate lobe)

Superior recess

Posterior

Pancreas, aorta (abdominal part), celiac trunk, splenic a. and v., gastrosplenic fold, left suprarenal gland, left kidney (superior pole)

Right

Liver, duodenal bulb

Left

Spleen, gastrosplenic ligament

Splenic recess

Fig. 12.7   Omental bursa in situ
Anterior view. Divided: Gastrocolic ligament. Retracted: Liver. Reflected: Stomach.

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Table 12.3 Boundaries of the omental foramen

The communication between the greater and lesser sacs is the omental (epiploic) foramen (see arrow in Fig. 12.7).

Direction

Boundary

Anterior

Hepatoduodenal ligament with the portal v., proper hepatic a., and bile duct

Inferior

Duodenum (superior part)

Posterior

Inferior vena cava, diaphragm (right crus)

Superior

Liver (caudate lobe)

Mesenteries & Posterior Wall

Fig. 12.8   Mesenteries and organs of the peritoneal cavity
Anterior view. Removed: Stomach, jejunum, and ileum. Reflected: Liver.

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Fig. 12.9   Posterior wall of the peritoneal cavity
Anterior view. Removed: All intraperitoneal organs. Revealed: Structures of the retroperitoneum (see Table 12.4 and p. 180).

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Contents of the Pelvis

Fig. 12.10   Male pelvis

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Fig. 12.11   Female pelvis

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Peritoneal Relationships

Fig. 12.12   Peritoneal relationships in the pelvis: Female

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Fig. 12.13   Peritoneal relationships in the pelvis: Male

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Pelvis & Perineum

Fig. 12.14   Pelvis and urogenital triangle
Coronal section, anterior view.

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Fig. 12.15   Pelvis: Coronal section Anterior view.

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Transverse Sections

Fig. 12.16   Abdomen: Transverse section
Inferior view.

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Fig. 12.17   Pelvis: Transverse section
Inferior view.

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