1 Know what a set and an element are. 2  Write a mathematical statement with an equal sign or an inequality.  Identify what numbers belong to the set of natural numbers, whole numbers, integers, rational numbers, irrational numbers, and real numbers.
Discogenic spondylosis, which is often thought of as a form of spinal osteoarthritis, refers to a degenerative condition that affects the joints of the spine.
Infection can also arise following surgery or injection of the disc space or via contiguous spread from adjacent soft tissue infection. The terms vertebral osteomyelitis and discitis are often used interchangeably, and the diagnosis and management of the two entities are similar in most patients. The term pyogenic spondylitis refers to either vertebral osteomyelitis or discitis. Pyogenic vertebral osteomyelitis will be reviewed here.