#Rib cage diagrams free#

Its head has a single facet because it only articulates with the T1 vertebra, and its body has two transverse grooves crossing its superior surface for the subclavian artery and vein. Its body is the widest and is nearly horizontal.

So, the 1st rib is the broadest, shortest, and most sharply curved of the seven true ribs. Now, the 1st, 2nd, 10th through 12th rib are atypical ribs because they are unlike the typical ribs in various ways. The internal surface of the body is concave and has a costal groove that’s parallel to the inferior border of the rib, which provides protection for the intercostal nerves and vessels at that level. This angle also demarcates the lateral limit of attachment of the deep back muscles to the ribs. The body is thin, flat, and curved, especially at the costal angle, where the rib makes an anterolateral turn. The tubercle, located at the junction of the neck and body, has a smooth articular part that connects with the corresponding transverse process of the vertebra and a rough nonarticular part where the costotransverse ligament attaches. The neck connects the head with the body at the level of the tubercle. The inferior facet articulates with the numerically corresponding vertebra, and the superior facet articulates with the vertebra above it. On a posterior view, the head of a typical rib is wedge shaped and has two facets - superior and inferior - that are separated by the crest of the head.

Typical ribs are the 3rd through the 9th pair of ribs and have the following components: head, neck, tubercle, and body. Ribs can further be classified as either typical or atypical ribs.

The cartilages of these ribs don’t connect anteriorly to the sternum at all instead they end up in the posterior abdominal musculature.

#Rib cage diagrams free#

The floating ribs or vertebral or free ribs are the 11th, the 12th pair of ribs, and sometimes the 10th pair of ribs. The false or vertebrochondral ribs are the 8th, 9th, and usually the 10th pair of ribs, and their cartilages are connected to the cartilage of the rib above them.Ĭonsequently, their connection to the sternum is indirect. The true or vertebrosternal ribs are the first 7 pairs of ribs, and they attach directly to the sternum through their own costal cartilages. There are three types of ribs based on their connection to the sternum: true, false, and floating ribs. They’re curved, flat, lightweight, and highly resilient bones.Įach rib has a spongy interior that contains bone marrow or hematopoietic tissue which forms blood cells. Okay, let’s start talking about the ribs, which form most of the thoracic cage. The structures that cover its posterior aspect are considered to belong to the back.Īdditionally, the mammary glands of the breasts lie within the thoracic wall subcutaneous tissue, and the anterolateral axioappendicular muscles are also considered part of the thoracic wall. Now, the true thoracic wall includes the thoracic cage and the muscles between the ribs and the skin, as well as subcutaneous tissue, muscles and fascia that cover its anterolateral aspect. The ribs and costal cartilages form the largest part of the thoracic cage and both can be identified numerically, going from 1 to 12 for the ribs, and going from 1 to 10 for the costal cartilage, as ribs 11 and 12 do not have an associated costal cartilage. This skeleton is made up of the sternum, 12 pairs of ribs and associated costal cartilages, as well as 12 thoracic vertebrae and intervertebral discs interposed between them. The thoracic skeleton forms the osteocartilaginous thoracic cage that protects the thoracic viscera and some of the abdominal organs. The thorax is the area between the neck and abdomen and consists of the thoracic cavity, its contents, and the walls that surround it.