Like other organs, the chest has a protective structure to shield the organs such as the heart, lungs, liver, etc., known as ‘the thoracic wall or thorax. Skin, fat, some muscles, and bones such as ribs, cartilage, and sternum combined make a wall to protect the vital organs.
It also works as a protective cavity inside the abdomen. The chest wall not only works as a protective shield, but it also performs some other functions such as;
- Support breathing
- Support upper arms and shoulder movement
This article will give a brief overview of chest wall anatomy, its structure, and its functioning. Moreover, this article also deals with the health problems related to the chest walls.
Chest Wall Anatomy
The thoracic skeleton (includes the chest wall) is located below your neck and above your tummy. It’s like a box made up of muscles, fat, skin, cartilage, and bones. The primary function of the chest wall is to protect and enclose your essential organs, such as your heart, lungs, and liver.
It is the thoracic wall consists of a framework of bones that are held closely by thoracic vertebrae. The ribs that surround the lateral and anterior thoracic cavities are formed by it.
The manubrium and sternum are connected by the first nine ribs, which bend around the lateral thoracic wall. Ribs 10-12 are short ribs that join to the ribs’ coastal borders slightly above them and do not reach the sternum due to their short path.
The anterior chest wall is defined by the sternum, the vertical bone of the chest that is made up of the following three discrete bone segments of varying size and shape:
- The thick manubrium
- The long body of the sternum, and
- The xiphoid process
It develops separately from the ribs. The sternum may not fully grow in sporadic situations, exposing the underlying heart. The manubrium is the most superior region of the sternum that first forms during embryogenesis.
The sternal body and xiphoid process develops in tandem with the manubrium. However, the manubrium is anatomically placed between the T3 and T4 thoracic vertebral bodies. It is also the sternum’s largest and thickest portion.
The existence of the suprasternal notch on a physical examination of the chest is one distinguishing feature of the manubrium.
The thick attachment from the clavicles can be felt on each side of this notch. Some thoracic surgeons will make a midline incision in the manubrium to access the superior mediastinum, suprasternal goiter, or thymus.
Chest Wall Functioning
The mediastinum and two pleural cavities, one on each side, split the thoracic cavity into three compartments. The heart and major vessels are housed in the mediastinum, whereas the lungs are located in the pleural cavities.
The thoracic cage protects the lungs and heart and provides attachments for the thoracic, upper extremity, back, and abdomen muscles. It connects to the neck via the thoracic outlet and divides the abdomen inferiorly via the respiratory diaphragm.
The thoracic wall’s limits are significant landmarks for clinicians and surgeons doing sternotomies and pericardiocentesis in cardiac tamponade and thoracentesis patients for pleural effusion. Its structure includes;
- The sternum and costal cartilages from the anterior thoracic wall.
- The ribs and intercostal spaces make the lateral thoracic wall.
- The thoracic vertebrae and intervertebral discs form the posterior thoracic wall.
- The suprapleural membrane develops the superior thoracic wall.
- Lastly, the respiratory diaphragm makes the inferior thoracic wall.
Chest wall’s Health issues
Heart and lung disorders are potential concerns in the chest area. However, the chest wall might be afflicted with health problems as well. Following are the chest wall health issues;
1. Infection
Bacteria and viruses can infect your internal organs and chest wall. Following are the types of common infections;
- Pleurisy
- Costochondritis
- Empyema
Pleurisy is a lung illness that causes adverse effects on membranes that connect your chest wall to the lungs. When you breathe, the two layers of membranes move seamlessly together, while pleurisy creates inflammation, friction, and pain during breathing.
The chest wall is also affected by costochondritis, in which the cartilage that connects your sternum and ribs becomes inflamed.
2. Tumors
Tumors can form on the chest wall just like they appear anywhere else on your body. It happens when your tissue’s cells renew and multiply but grow improperly and form a tumor. Tumors in the chest wall are usually benign (noncancerous) and come in three types;
- Fibrous dysplasia
- Osteochondroma
- Chondroma
Sarcomas, which start in your bones, cartilage, or soft tissues, are the most common cancerous tumors in the chest wall.
3. Problems with the structure
Pectus excavatum is one of the most common problems involving the construction of the chest wall. Your ribs grow abnormally with this illness, affecting the structure of your chest wall and giving it a sunken, caved-in appearance.
It’s only a cosmetic concern in moderate cases, but if it’s severe, it might prevent healthy breathing.
References:
- https://www.rocklandthoracicandvascular.com/blog/ what is the chest wall
- https://www.sciencedirect.com/topics/medicine-and-dentistry/thoracic-wall
- https://www.ncbi.nlm.nih.gov/books/NBK535414/