where does the head of the rib articulate with
Articulation of head of rib The articulations of the heads of the ribs (or costocentral articulations) constitute a series of gliding or arthrodial joints, and are formed by the articulation of the heads of the typical ribs with the facets on the contiguous margins of the bodies of the thoracic vertebrae and with the intervertebral fibrocartilages between them; the first, eleventh and twelfth ribs each articulate with a single vertebra.
Lung The lungs are located in the chest on either side of the heart in the rib cage. They are conical in shape with a narrow rounded apex at the top, and a broad concave base that rests on the convex surface of the diaphragm.[1] The apex of the lung extends into the root of the neck, reaching shortly above the level of the sternal end of the first rib. The lungs stretch from close to the backbone in the rib cage to the front of the chest and downwards from the lower part of the trachea to the diaphragm.[1] The left lung shares space with the heart, and has an indentation in its border called the cardiac notch of the left lung to accommodate this.[2][3] The front and outer sides of the lungs face the ribs, which make light indentations on their surfaces. The medial surfaces of the lungs face towards the centre of the chest, and lie against the heart, great vessels, and the carina where the trachea divides into the two main bronchi.[3] The cardiac impression is an indentation formed on the surfaces of the lungs where they rest against the heart.