thoracic cavity

or chest cavity

Second largest hollow space of the body, enclosed by the ribs, vertebral column, and breastbone and separated from the abdominal cavity by the diaphragm. It contains the lungs and bronchi, part of the esophagus and trachea, and the heart and major blood vessels. A membrane called the pleura lines the cavity (parietal pleura) and continues over the lung (visceral pleura) and the rest of the cavity's contents, defining a space called the mediastinum. Disorders include blood (hemothorax) or air (pneumothorax, which can lead to atelectasis) in the pleural cavity and inflammation of the pleura (pleurisy).

Learn more about thoracic cavity with a free trial on Britannica.com.

The chest is a part of the anatomy of humans and various other animals sometimes referred to as the thorax.

Chest anatomy - Humans and other hominids

In hominids, the chest is the region of the body between the neck and the abdomen, along with its internal organs and other contents. It is mostly protected and supported by the ribcage, spine, and shoulder girdle. Contents of the chest include the following:

• organs
• heart
• lungs
• muscles
• major and minor pectoral muscles
• trapezius muscles and neck
• internal structures
• diaphragm
• esophagus
• trachea
• xiphoid process
• arteries and veins
• aorta
• superior vena cava
• inferior vena cava
• pulmonary artery
• bones
• the shoulder socket containing the upper part of the humerus
• scapula
• sternum
• thoracic portion of the spine
• collarbone
• ribcage
• Floating ribs
• external structures
• nipples
• mammary glands
• thoracic abdomen (stomach, kidney/adrenal, pancreas, spleen, and lower oesophagus)

In humans, the portion of the chest protected by the ribcage is also called the thorax.

Chest anatomy - Other animals

In insects and other creatures with an exoskeleton, the area corresponding to the chest is called the thorax.

In four legged mammals, the mammary glands and nipples are located closer to the back legs, and are therefore not part of the chest. Otherwise, the anatomy contains similar internal organs in different configurations.

Chest injury

Injury to the chest (also referred to as chest trauma, thoracic injury, or thoracic trauma) results in up to ¼ of all deaths due to trauma in the United States.

References

See also

• Thoracic cavity
• Pectus excavatum
• Pectus carinatum
• Breast
• Chest hair
• Barechested