Fasciae of body cavities

The fasciae of the body cavities are connective tissue layers that line and support the internal surfaces of the thoracic, abdominal, and pelvic walls, as well as the viscera contained within them. These fasciae occupy the subserous plane, situated between the musculoskeletal walls and the serous membranes of the body cavities.

They include the parietal fascia, which lies external (superficial) to the parietal serous membrane (such as the parietal pleura or parietal peritoneum), and the visceral fascia, which lies deep (internal) to the visceral serous membrane (such as the visceral peritoneum) surrounding the organs.

An additional connective tissue layer, the extraperitoneal fascia, is present particularly in the abdominopelvic region. It occupies the space between the parietal and visceral fasciae on one side and the parietal and visceral peritoneum on the other.

Together, these fasciae of the body cavities provide structural support, permit controlled mobility of the viscera, and form pathways for blood vessels, lymphatics, and nerves. They also contribute to the formation of mesenteries, ligaments, and connective tissue planes that stabilize and organize the internal organs within each body cavity.