The question of whether lungs are located in the back is a common point of confusion, often stemming from the feeling of breathing and discomfort in the posterior body. While the lungs are not situated only in the front, they occupy a significant posterior space. These organs are the primary components of the respiratory system, housed within the protective rib cage.
Where the Lungs Are Located (The Thoracic Cavity)
The lungs are housed within the thoracic cavity, the large, central space in the chest that also contains the heart and major blood vessels. They sit on either side of the heart, protected by the rib cage, which wraps around the entire upper torso. The misconception that the lungs are only in the front arises because the chest is the most visible part of this cavity. The thoracic cavity extends far back to the vertebral column, meaning the lungs occupy a substantial amount of space against the back.
The rib cage acts as a bony shield, protecting the delicate lung tissue. This structure is made up of the ribs, the sternum (breastbone) in the front, and the thoracic vertebrae of the spine in the back. Because the chest wall is deepest from front to back, the lungs are extensive, with the greater part of the lower lobes positioned toward the posterior aspect of the body.
Mapping the Lungs: Boundaries and Extent
The specific anatomical boundaries help map the lungs’ extent within the thoracic cavity. The very top of the lung, known as the apex, extends upward slightly above the level of the first rib and into the root of the neck. Conversely, the bottom of the lung, called the base, is concave and rests directly on the dome-shaped diaphragm muscle that separates the chest from the abdomen.
The posterior border of the lungs, which lies against the back, is quite thick and long, extending from the seventh cervical vertebra (C7) down to the tenth thoracic vertebra (T10). The right and left lungs are not perfectly symmetrical due to the positioning of other organs in the chest. The right lung is both shorter and wider to accommodate the liver sitting beneath the diaphragm on the right side. The left lung is slightly smaller, featuring an indentation known as the cardiac notch, which provides space for the heart.
Why Lung Discomfort Can Be Felt in the Back
The sensation of pain or discomfort that feels like it originates in the back of the lungs is a common reason people question their location. Paradoxically, the lung tissue itself has very few pain receptors, meaning injury often does not register as pain. The sharp, localized pain people feel when breathing deeply or coughing is usually caused by irritation of the pleura, the double-layered membrane lining the lungs and the inside of the chest wall.
The outer layer of the pleura, called the parietal pleura, is rich with sensory nerve endings. When this lining becomes inflamed (pleurisy or pleuritis), the layers rub against each other, causing intense discomfort. Because the nerve pathways supplying the pleura share connections with nerves that supply the chest and back muscles, this pain can be felt away from the source, a phenomenon known as referred pain. Irritation of the posterior pleura can send signals that the brain interprets as pain originating in the back or shoulder.
Furthermore, pain in the back that mimics lung discomfort can also be related to musculoskeletal issues surrounding the rib cage. Conditions like costochondritis, inflammation of the cartilage connecting the ribs to the breastbone, can cause sharp chest and back pain. Persistent coughing from a respiratory infection can strain the muscles and ligaments of the back, creating a sensation of posterior lung pain.