Transverse myelitis is a neurological disorder caused by inflammation of the spinal cord, which carries nerve signals from the brain to the rest of the body. The segment of the spinal cord that has inflammation or damage determines the symptoms a person has. Generally, inflammation at one segment causes symptoms at that level and below that level. Most commonly, the upper spinal cord is affected, causing impaired leg movement, and problems controlling the bowel and bladder. The cause of Transverse myelitis may be unknown (idiopathic) or it may be associated with a wide variety of underlying health problems, including infections, immune system disorders, and other inflammatory disorders. Tests that may be used to diagnose Transverse myelitis include MRI to look for compression or inflammation of the spinal cord, and a lumbar puncture (spinal tap) to look for evidence of inflammation in the fluid surrounding the spinal cord (cerebrospinal fluid).