torace

Torace, or thorax, is the central part of the trunk between the neck and the abdomen. In humans, it encloses the thoracic cavity and contains the heart and lungs, protected by the rib cage and sternum. The term is used in several languages; in English this region is usually called the thorax or chest.

The thorax is bounded posteriorly by the thoracic vertebrae, laterally by the ribs, anteriorly by the sternum, and inferiorly by the diaphragm. It comprises the thoracic skeleton—twelve vertebrae, twelve pairs of ribs with costal cartilage, and the sternum (manubrium, body, xiphoid process). The intercostal muscles and diaphragm are key respiratory muscles.

The thoracic cavity is divided by the mediastinum into two pleural cavities. It contains the lungs, each within a pleural sac, and the mediastinal contents, including the heart, great vessels, trachea, esophagus, and thymus (more prominent in children). The pericardial sac surrounds the heart.

Functions of the torace include breathing, protection of the heart and lungs, and providing attachments for muscles that move the upper limbs and maintain posture. The diaphragm and intercostal muscles enable ventilation by expanding and compressing the thoracic volume.

Nerve and blood supply: intercostal nerves (T1–T11) innervate the intercostal muscles and overlying skin; the phrenic nerve (C3–C5) innervates the diaphragm. Arterial supply comes mainly from the internal thoracic arteries and posterior intercostal arteries; venous return follows the azygos system to the superior vena cava.

Clinical relevance: traumatic injury, pneumothorax, pleural effusion, rib fractures, and mediastinal masses are common thoracic conditions. Surgical procedures may involve thoracic cavity access via the chest walls.