The most common organism in spinal infection is from the bacteria Staphylococcus aureus which typically exists on human skin, followed by Escherichia coli. Most spine infections occur in the lumbar spine because of the blood supply to this region of the spine.
Feudalism, a system of political and military relationships, evolved in western Europe. The feudal system was a simple but effective means of medieval government in which the king rented land to barons, who provided him knights and taxes
This article is about the classic, or medieval, Western European form of feudalism. For feudalism as practiced in other societies, as well as that of the Europeans, see Examples of feudalism.