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.
Ribs, or costae, are elongated, curved, flattened bones that originate on or between the thoracic vertebrate and end in the wall of the thoracic cavity. Humans have 12 pairs of ribs, the first 7 are true ribs connected to the sternum by separate cartilaginous extensions called the coastal cartilages. Ribs 8-12 are called false ribs because they do not connect directly to the sternum. Ribs 11&12 are called floating ribs because they do not connect to the sternum at all.