Spondylolysis and Spondylolisthesis

Spondylolysis is a type of stress fracture in the spine. The fracture occurs in the back of the bone, in an area called the pars interarticularis. The condition is the most common cause of low back pain in adolescent athletes and thought to be an overuse injury that results from repetitive microtrauma to the bone. The term spondylolysis originates from the Greek words spondylo, meaning “vertebrae” (or bone of the spine), and lysis, meaning “to dissolve.”

A fracture of the pars interarticularis may become unstable, allowing the vertebrae to slip out of position. This slippage is called spondylolisthesis. ...