Espiral AtlasTypical rib (3rd–9th)
costa
Study entry
Parts
A flat, curved, light and very elastic bone, with red bone marrow inside. Wedge-shaped head, with two articular surfaces separated by a crest; neck, which connects the head to the shaft; tubercle, at the junction of the neck with the shaft, with a smooth articular part and a rough one; thin, flat, curved shaft, which turns forward and to the side at the angle; on the inner surface, the costal groove, next to the lower border. The areas are painted on the 6th rib.
Joints
Costovertebral: the head with the body of the vertebra of the same number and with that of the vertebra above; the tubercle with the transverse process of the vertebra of the same number. In front, it continues in the costal cartilage (the 1st–7th reach the sternum directly, the 8th–9th through the cartilage above).
Clinical
The middle ribs are the ones that fracture most, usually from a blow or compression; the weakest point lies just in front of the angle.
Source: cap. 4, «Costillas, cartílagos costales y espacios intercostales» y cuadro clínico «Fracturas de costilla»