What are the 4 parts of the thoracic cage?
The thoracic cage (human rib cage) is a bony and cartilaginous structure which surrounds the thoracic cavity and supports the pectoral girdle, forming a core portion of the human skeleton. A typical human rib cage consists of 24 ribs, the sternum (with xiphoid process), costal cartilages, and the 12 thoracic vertebrae.
What anatomical structures make up the thoracic wall?
The thoracic wall consists of a bony framework that is held together by twelve thoracic vertebrae posteriorly which give rise to ribs that encircle the lateral and anterior thoracic cavity. The first nine ribs curve around the lateral thoracic wall and connect to the manubrium and sternum.
How many bones are there in the thoracic cage?
The rib cage surrounds the lungs and the heart, serving as an important means of bony protection for these vital organs.In total, the rib cage consists of the 12 thoracic vertebrae and the 24 ribs, in addition to the sternum.
What are the three main parts of the thoracic cage?
It consists of three parts: the manubrium, body, and xiphoid process. The manubrium is the wider, superior portion of the sternum.
What are ribs 11 and 12 called?
The last false ribs (11–12) are also called floating (vertebral) ribs, because these ribs do not attach to the sternum at all. Instead, the ribs and their small costal cartilages terminate within the muscles of the lateral abdominal wall.
How is the thoracic cage formed?
The thoracic cage (rib cage) is the skeleton of the thoracic wall. It is formed by the 12 thoracic vertebrae, 12 pairs of ribs and associated costal cartilages and the sternum. The thoracic cage takes the form of a domed bird cage with the horizontal bars formed by ribs and costal cartilages.
What is the general shape of the thoracic cage?
The thoracic cage, a flexible framework of bones and cartilage, is conical in shape. It is narrower at the top and broadens to fit and protect some critical organs of respiration and circulation—that is, the lungs and heart.
What are 3 parts of the sternum?
The sternum is a partially T-shaped vertical bone that forms the anterior portion of the chest wall centrally. The sternum is divided anatomically into three segments: manubrium, body, and xiphoid process. The sternum connects the ribs via the costal cartilages forming the anterior rib cage.
What is the most inferior portion of the sternum?
The inferior tip of the sternum is called the xiphoid process, meaning “sword shaped.”
Why are the last two ribs called floating ribs?
The last two pairs of ribs at the very bottom of the rib cage do not attach to the sternum at all. These ribs are referred to as “floating ribs” as their only attachment is found at the back of the rib cage, anchored to the vertebrae of the spine.