Trunk

The trunk is the central part of the body, located between the neck and the limbs (thoracic and pelvic).

It is divided into four major parts:

• The back: This corresponds to the vertebral column (thoracic, lumbar, and sacral parts) and the dorsal muscles, which ensure the support and mobility of the entire body. This part is fundamental for maintaining posture and for protecting the spinal cord;

• The thorax: It is defined by the thoracic cavity (ribs, sternum, and thoracic vertebrae) and contains the lungs, the heart, and the large blood vessels. The thorax plays an essential role in breathing thanks to the movements of the ribs and the diaphragm;

• The abdomen: Located below the thorax, it extends to the pelvis. It houses most of the digestive organs (stomach, intestines, liver, pancreas, spleen) as well as the kidneys and adrenal glands. It is bounded by the abdominal muscles (rectus, obliques, transverse) that provide support for the viscera and participate in breathing and locomotion;

• The pelvis: This is the terminal part of the trunk, in continuity with the abdomen. It includes the pelvic bones (pelvis) and houses the urogenital organs as well as the rectum. It contributes to body stability, supports the abdominal viscera, and is involved in reproductive functions.