| Costal margin | |
|---|---|
 Anterior surface of sternum and costal cartilages. (The costal margin forms a large upside-down V on the inferior border.) | |
| Details | |
| Identifiers | |
| Latin | arcus costalis |
| TA98 | A02.3.04.006 |
| TA2 | 1101 |
| FMA | 7569 |
| Anatomical terminology | |
The costal margin, also known as the costal arch, [1] is the lower edge of the chest (thorax) formed by the bottom edge of the rib cage.
The costal margin is the medial margin formed by the cartilages of the seventh to tenth ribs. It attaches to the body and xiphoid process of the sternum. [2]
The thoracic diaphragm attaches to the costal margin. [3]
The costal angle is the angle between the left and right costal margins where they join the sternum. [2]
The costal margins somewhat protect the higher abdominal organs, such as the liver. [4] [5]
The costal margin may be used for tissue harvesting of cartilage for use elsewhere in the body, such as to treat microtia. [4]
Different abdominal organs may be palpated just below the costal margin, such as the liver on the right side of the body. [5]
Pain across the costal margin is most commonly caused by costochondritis. [6]
The costal paradox, also known as Hoover's sign and the costal margin paradox, is a sign where the costal angle decreases upon inspiration rather than increasing, indicating chronic obstructive pulmonary disease. [2]
In vertebrate anatomy, ribs are the long curved bones which form the rib cage, part of the axial skeleton. In most tetrapods, ribs surround the chest, enabling the lungs to expand and thus facilitate breathing by expanding the chest cavity. They serve to protect the lungs, heart, and other internal organs of the thorax. In some animals, especially snakes, ribs may provide support and protection for the entire body.
The rib cage is an endoskeletal enclosure in the thorax of most vertebrate animals that comprises the ribs, vertebral column and sternum, which protects vital organs such as the heart, lungs and great vessels. The circumferential enclosure formed by left and right rib cages, together known as the thoracic cage, is a semi-rigid bony and cartilaginous structure which surrounds the thoracic cavity and supports the shoulder girdles to form the core part of the axial skeleton.
The xiphoid process, also referred to as the ensiform process, xiphisternum, or metasternum, constitutes a small cartilaginous process (extension) located in the inferior segment of the sternum, typically ossified in adult humans. Both the Greek-derived term xiphoid and its Latin equivalent, ensiform, connote a "swordlike" or "sword-shaped" morphology.
The thorax or chest is a part of the anatomy of mammals and other tetrapod animals located between the neck and the abdomen. In insects, crustaceans, and the extinct trilobites, the thorax is one of the three main divisions of the creature's body, each of which is in turn composed of multiple segments.
The thoracic diaphragm, or simply the diaphragm, is a sheet of internal skeletal muscle in humans and other mammals that extends across the bottom of the thoracic cavity. The diaphragm is the most important muscle of respiration, and separates the thoracic cavity, containing the heart and lungs, from the abdominal cavity: as the diaphragm contracts, the volume of the thoracic cavity increases, creating a negative pressure there, which draws air into the lungs. Its high oxygen consumption is noted by the many mitochondria and capillaries present; more than in any other skeletal muscle.
In anatomy, the epigastrium is the upper central region of the abdomen. It is located between the costal margins and the subcostal plane. Pain may be referred to the epigastrium from damage to structures derived from the foregut.
The celiacartery, also known as the celiac trunk or truncus coeliacus, is the first major branch of the abdominal aorta. It is about 1.25 cm in length. Branching from the aorta at thoracic vertebra 12 (T12) in humans, it is one of three anterior/ midline branches of the abdominal aorta.
The cricothyroid ligament is a ligament in the neck. It connects the cricoid cartilage to the thyroid cartilage. It prevents these cartilages from moving too far apart. It is cut during an emergency cricothyrotomy to treat upper airway obstruction.
The transverse abdominal muscle (TVA), also known as the transverse abdominis, transversalis muscle and transversus abdominis muscle, is a muscle layer of the anterior and lateral abdominal wall, deep to the internal oblique muscle. It is thought by most fitness instructors to be a significant component of the core.
An abdominal examination is a portion of the physical examination which a physician or nurse uses to clinically observe the abdomen of a patient for signs of disease. The abdominal examination is conventionally split into four different stages: first, inspection of the patient and the visible characteristics of their abdomen. Auscultation (listening) of the abdomen with a stethoscope. Palpation of the patient's abdomen. Finally, percussion (tapping) of the patient's abdomen and abdominal organs. Depending on the need to test for specific diseases such as ascites, special tests may be performed as a part of the physical examination. An abdominal examination may be performed because the physician suspects a disease of the organs inside the abdominal cavity (including the liver, spleen, large or small intestines), or simply as a part of a complete physical examination for other conditions. In a complete physical examination, the abdominal exam classically follows the respiratory examination and cardiovascular examination.
The sternal angle is the projecting angle formed between the manubrium and body of a sternum at their junction at the manubriosternal joint.
The intercostal nerves are part of the somatic nervous system, and arise from the anterior rami of the thoracic spinal nerves from T1 to T11. The intercostal nerves are distributed chiefly to the thoracic pleura and abdominal peritoneum, and differ from the anterior rami of the other spinal nerves in that each pursues an independent course without plexus formation.
The abdomen is the part of the body between the thorax (chest) and pelvis, in humans and in other vertebrates. The abdomen is the front part of the abdominal segment of the torso. The area occupied by the abdomen is called the abdominal cavity. In arthropods, it is the posterior tagma of the body; it follows the thorax or cephalothorax.
In human anatomy, the superior epigastric veins are two or more venae comitantes which accompany either superior epigastric artery before emptying into the internal thoracic vein. They participate in the drainage of the superior surface of the diaphragm.
The costal cartilages are bars of hyaline cartilage that serve to prolong the ribs forward and contribute to the elasticity of the walls of the thorax. Costal cartilage is only found at the anterior ends of the ribs, providing medial extension.
In anatomy, the division of the abdomen into regions can employ a nine-region scheme. The hypochondrium refers to the two hypochondriac regions in the upper third of the abdomen; the left hypochondrium and right hypochondrium. They are located on the lateral sides of the abdominal wall respectively, inferior to (below) the thoracic cage, being separated by the epigastrium.
Thoracic splanchnic nerves are splanchnic nerves that arise from the sympathetic trunk in the thorax and travel inferiorly to provide sympathetic supply to the abdomen. The nerves contain preganglionic sympathetic fibers and general visceral afferent fibers.
The sternocostal joints, also known as sternochondral joints or costosternal articulations, are synovial plane joints of the costal cartilages of the true ribs with the sternum. The only exception is the first rib, which has a synchondrosis joint since the cartilage is directly united with the sternum. The sternocostal joints are important for thoracic wall mobility.
The rectus sheath is a tough fibrous compartment formed by the aponeuroses of the transverse abdominal muscle, and the internal and external oblique muscles. It contains the rectus abdominis and pyramidalis muscles, as well as vessels and nerves.
The sternum or breastbone is a long flat bone located in the central part of the chest. It connects to the ribs via cartilage and forms the front of the rib cage, thus helping to protect the heart, lungs, and major blood vessels from injury. Shaped roughly like a necktie, it is one of the largest and longest flat bones of the body. Its three regions are the manubrium, the body, and the xiphoid process. The word sternum originates from Ancient Greek στέρνον (stérnon) 'chest'.
