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.
There are 24 ribs in the human body, divided into two sets of 12 curved, flat bones. Each one is attached by cartilage at the back to the thoracic vertebrae. The first upper seven ribs are known as 'true ribs' and are directly attached by cartilage to a long flat bone at the centre of the chest called the sternum (breastbone). The remaining pairs of ribs are known as âfalse ribsâ. The eighth, ninth and tenth ribs are also attached to the sternum but not directly.