In its classic definition, by FranÃ§ois-Louis Ganshof (1944), feudalism describes a set of reciprocal legal and military obligations among the warrior nobility revolving around the three key concepts of lords, vassals and fiefs.
The exact cause of intracardiac echogenic foci remains unclear; however, they appear to be caused by small deposits of calcium in the papillary muscle of the fetal heart.
Causes of neurogenic claudication. Spinal stenosis is often the primary factor behind neurogenic claudication. Spinal stenosis is a degenerative spine condition in which the passageways that allow the nerve roots to exit the spinal canal become constricted, often placing pressure on these nerves. Spinal stenosis also can occur in the spinal canal itself, placing painful pressure directly on the spinal cord.