What causes a pulmonary embolism? Blood clots can form for a variety of reasons. Pulmonary embolisms are most often caused by deep vein thrombosis, a condition in which blood clots form in veins deep in the body. The blood clots that most often cause pulmonary embolisms begin in the legs or pelvis.
All ribs are attached posteriorly to the thoracic vertebrae. The neck of the rib is the flattened part that extends laterally from the head. The neck is about 3 cm long, and is placed in front of the transverse process of the lower of the two vertebrae with which the head articulates.
12 pairs (24). 8-12 rib pairs are called false ribs. Our thoracic cage or rib cage is composed of 12 pairs of ribs, sternum, cartilages and thoracic vertebrae. Of the 12 pairs of ribs, the first 7 pairs (1-7) are attached to vertebrae posteriorly and sternum anteriorly (with costal cartilage). These rib pairs are called true ribs.