rib cage

Examples of rib cage in the following topics:

• Thoracic Cage: Ribs

  • Ribs are long, curved bones that form the rib cage surrounding the thorax.
  • The thoracic cage can expand and contract to facilitate breathing in association with the diaphragm; it also protects the lungs, heart, and other organs of the thoracic cavity.
  • Finally, the shaft forms the majority of the length of the rib as it curves around the thoracic cavity forming the rib cage.
  • Rib 1 is the shortest and most curved of the ribs.
  • Lateral view of rib cage showing its connections to vertebrae.

• Overview of the Axial Skeleton

  • It is composed of: the human skull, the ossicles of the middle ear, the hyoid bone of the throat, the rib cage (including the sternum), and the vertebral column.
  • The human rib cage, also known as the thoracic 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, costal cartilages, and the 12 thoracic vertebrae .

• Thoracic Cage: Sternum

  • The sternum or breastbone is a long, flat, bony plate connected to the rib bones via cartilage that forms the anterior section of the rib cage.
  • Together with the anterior ribs it helps to protect the heart and lungs from damage, as well as facilitates the expansion and contraction of the thoracic cavity during respiration.
  • The manubrium is the most superior region of the sternum and articulates with the clavicles or collarbones and the first pair of ribs.
  • Located below the manubrium, the gladiolus is the longest portion of the sternum and articulates with the ribs, either directly or indirectly, through the costal cartilage
  • Explain the structure and function of the sternum in the thoracic cage

• Rib Fracture, Dislocation, and Separation

  • Joint dislocations and rib cage fractures are painful but treatable injuries involving the axial skeleton.
  • A rib fracture is a break or fracture in one or more of the bones making up the rib cage.
  • Fractures of the first and second ribs may be more likely to be associated with head and facial injuries than are other rib fractures.
  • The middle ribs are the ones most commonly fractured.
  • Rib fractures are usually quite painful because the ribs have to move to allow for breathing.

• Anterior Muscles

  • All intercostal muscles originate on the lower border of a rib and attach to the upper border of the rib below.
  • Diaphragm - The diaphragm is a large, flat, sheet-like muscle that extends horizontally underneath the rib cage.
  • Functionally, the diaphragm separates the thoracic cavity, containing the lungs and heart and enclosed by the rib cage  from the abdominal cavity, which contains the digestive organs.
  • Attachments – Originates from the pubis and attaches to the lower edge of the rib cage and sternum.
  • The intercostals are muscles between the ribs that form the chest cavity wall.

• The Axial Skeleton

  • The rib cage is composed of 25 bones that include the 12 pairs of ribs plus the sternum.
  • The first seven pairs of ribs attach to the sternum with costal cartilage and are known as true ribs.
  • After rib seven, the size begins to decrease.
  • The 8th through 10th ribs have noncostal cartilage that connects them to the ribs above.
  • The last two ribs are called floating ribs because they do not attach to the sternum or to other ribs.

• Aging and the Respiratory System

  • Expiration follows relaxation of diaphragm and abdominal muscles, but can be increased by the downward action of abdominal muscles on the rib cage.
  • Auxiliary intercostal muscles stiffen and shape the rib cage.

• Human Axial Skeleton

  • The thoracic cage, also known as the ribcage, is the skeleton of the chest.
  • It consists of the ribs, sternum, thoracic vertebrae, and costal cartilages .
  • Costal cartilages connect the anterior ends of the ribs to the sternum, with the exception of rib pairs 11 and 12, which are free-floating ribs.
  • The thoracic cage, or rib cage, protects the heart and the lungs.
  • The axial skeleton consists of the bones of the skull, ossicles of the middle ear, hyoid bone, vertebral column, and rib cage.

• Lungs

  • The rib cage is a structure of bones that surrounds and protects the thoracic cavity, with 12 ribs protecting each of the two lungs.
  • The rib cage itself is also able to expand and contract to some degree during breathing, through the action of other respiratory and accessory respiratory muscles.

• Electrostatic Shielding

  • When an external electric field operates on a Faraday cage, the charges within the cage (which are mobile, as the cage is a conductor) rearrange themselves to directly counteract the field and thus "shield" the interior of the cage from the external field
  • The action of a Faraday cage may depend on whether or not it is grounded.
  • Consider a charge placed within a cage.
  • If the cage is not grounded, electrons in the cage will redistribute such that the interior wall of the cage takes on a charge opposite the internal charge.
  • As the field is applied, the negative charge from the cage migrates toward the positive end of the field, canceling the effects of the field at both ends of the cage.