MEDICAL DICTIONARY

Table of Contents

Abdominal cavity

The abdominal cavity is a large body cavity located in the abdomen and contains many vital organs. It is part of the larger abdominopelvic cavity, which also includes the pelvic cavity. The abdominal cavity is enclosed by the abdominal muscles, spine, and diaphragm, and it plays a critical role in housing and protecting key organs involved in digestion, excretion, and other physiological processes.

Anatomy and Structure

The abdominal cavity is bounded by:

  • Superiorly: The diaphragm, which separates the abdominal cavity from the thoracic cavity.
  • Inferiorly: The pelvic inlet, leading into the pelvic cavity.
  • Anteriorly and laterally: The abdominal muscles (rectus abdominis, transverse abdominis, internal and external obliques).
  • Posteriorly: The vertebral column and posterior abdominal muscles (psoas major, quadratus lumborum).

Contents of the Abdominal Cavity

The abdominal cavity contains several vital organs:

  • Digestive Organs: Stomach, small intestine (duodenum, jejunum, ileum), large intestine (including the cecum, ascending, transverse, descending, and sigmoid colon), liver, gallbladder, pancreas.
  • Excretory System: Kidneys, ureters.
  • Lymphatic Structures: Mesentery, lymph nodes, and major lymphatic vessels.
  • Vascular Structures: Abdominal aorta, inferior vena cava, and branches supplying blood to abdominal organs.
  • Other Structures: Spleen, adrenal glands.

Physiological Importance

  • Protection and Cushioning: The abdominal cavity, protected by layers of muscles and fat, safeguards the internal organs from external forces.
  • Support for Vital Functions: The organs within the cavity play roles in digestion (e.g., breaking down food), metabolism (e.g., liver processing nutrients), excretion (e.g., kidney filtration), and immune response (e.g., spleen filtering blood).
  • Intraperitoneal and Retroperitoneal Organs: Organs within the abdominal cavity are categorized based on their position relative to the peritoneum:
    • Intraperitoneal Organs: Stomach, spleen, liver, jejunum, ileum.
    • Retroperitoneal Organs: Kidneys, pancreas, parts of the duodenum.

Clinical Relevance

  • Peritonitis: Inflammation of the peritoneum, often due to infection or perforation of abdominal organs.
  • Ascites: Accumulation of fluid in the abdominal cavity, commonly associated with liver diseases like cirrhosis.
  • Hernias: Protrusion of organs or tissues through a weakened area in the abdominal wall.
  • Abdominal Trauma: Damage to organs within the cavity can occur due to blunt force, necessitating immediate medical attention.
References
  1. Gray, H. (1918). Gray’s Anatomy: The Anatomical Basis of Medicine and Surgery.
  2. Standring, S. (2020). Gray’s Anatomy: The Anatomical Basis of Clinical Practice. 41st Edition.
  3. Moore, K. L., & Dalley, A. F. (2018). Clinically Oriented Anatomy.
  4. Wikipedia contributors. “Abdominal Cavity.” Wikipedia, The Free Encyclopedia. Link.