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
The System of Feudalism. When the Western Roman Empire fell in 476 C.E., a state of chaos encompassed Western Europe for many centuries. Essentially, the people of Western Europe needed some form of a political system to defend themselves. Thus, feudalism developed. The system literally accounted for all aspects of a society, aside from religion.