1, sternal stalk: the sternal stalk is the upper part of the sternum, slightly flat, and forms a sternoclavicular joint with the sternal joint surface of the clavicle. The sternoclavicular joint is an important connection between the upper limb and the trunk. It participates in maintaining the integrity of the thoracic cavity and provides some protection for organs in the thoracic cavity, such as the heart and lungs.
2. Sternal body: The sternal body is the main part of the sternum, which is connected with the sternal stalk and extends downward. The sternum is arched, which helps to protect the organs in the chest. There is a longitudinal intercostal groove inside the sternum, which is the attachment of intercostal muscle, which helps to maintain the stability of the chest.
3. xiphoid process: xiphoid process is a conical protrusion under the sternum, which is connected with the seventh and eighth costal cartilage to form the costal xiphoid joint. Xiphoid process plays an important role in stabilizing thoracic cavity and protecting organs such as heart and lung. In the process of human breathing, xiphoid process also plays a certain role in assisting breathing.
The role of sternum in human body;
1. Support and protect the chest: The sternum is located in the human chest and is an important part of the chest. It provides support and protection for the heart, lungs and other important organs. The sternum, ribs, thoracic vertebrae and other structures * * * together form the skeleton frame of the thoracic cavity, maintaining the stability of the thoracic cavity and ensuring the normal function of organs in the thoracic cavity.
2. Participate in respiratory movement: the sternum, ribs, thoracic vertebrae and other structures participate in respiratory movement. When breathing, the sternum and ribs will fluctuate with breathing, changing the shape and size of the chest to help complete the breathing process. Especially xiphoid process, the movement of xiphoid process can assist the expansion and contraction of lungs and help breathing.
3. Attachment point of muscles and ligaments: The sternum is the attachment point of many muscles and ligaments, which is mainly involved in the movement and posture maintenance of upper limbs. For example, muscles such as pectoralis major and pectoralis minor can assist the movement of shoulders and upper limbs by attaching to the sternum. Ligaments such as intercostal ligaments are also attached to the sternum to help maintain the stability of the chest. The exertion of these functions ensures the normal physiological function and athletic ability of human body.