User:Calpoly90/sandbox

Spondylolisthesis is officially categorized into five different types:.[2][3]

Dysplastic spondylolisthesis is a rare congenital spondylolisthesis occurring because of a malformation of the lumbosacral junction resulting in small, incompetent facet joints.[citation needed]This affects the lumbar and/or the sacrum region (L5- S1) of the spine. Isthmic spondylolisthesis is the most common form of spondylolisthesis. Isthmic spondylolisthesis (also called spondylolytic spondylolisthesis) is a common condition with a reported prevalence of 5%-7% in the U.S. population. Isthmic spondylolisthesis is divided into three categories type IIA is caused by micro-fractures, type IIB is caused by an incomplete fracture to the pars and type IIC is caused by a complete fracture. A slip or fracture of the intravertebral joint is usually acquired between the ages of 6 and 16 years, but remains unnoticed until adulthood. Roughly 90% of these isthmic slips are low-grade (less than 50% slip) and 10% are high-grade (greater than 50% slip).[3]Isthmic occurs when a problem occurs in the pars interarticularis part of the vertebra. Degenerative spondylolisthesis is a disease of the older adult that develops as a result of facet arthritis and joint remodeling. Initially it occurs in the intervertebral disc. The main reason is due to fluid loss within the discs, causing a decrease in movement. Joint arthritis, and ligamentum flavum weakness, may result in slippage of a vertebrae. Degenerative forms are more likely to occur in women, persons older than fifty, and African-Americans.[3] Traumatic spondylolisthesis is very rare and results from acute fractures in various areas of the neural arch, other than the pars. [4]   Pathologic spondylolisthesis has been associated with damage to the posterior elements[which?] from metastases or metabolic bone disease. These slips have been reported in cases of Paget's disease of bone, tuberculosis, giant-cell tumors, and tumor metastases.[citation needed]