is a disorder in which a cyst, called a syrinx, forms within the spinal cord. This cyst expands and elongates over time, destroying the center of the spinal cord which can result in pain, weakness, stiffness in the back, shoulders, arms, or legs, headaches, and insensitivity to temperature (especially in the hands). Symptoms vary from person to person. Syringomyelia is often related to a congenital abnormality of the brain called a Chiari I malformation, but may also occur as a complication of trauma, meningitis, hemorrhage, a tumor, or arachnoiditis. Symptoms may appear months or even years after the initial injury. Some cases of syringomyelia are familial, although this is rare. Treatment often involves surgery and avoiding activities that involve straining. Drainage of the cysts using a catheter, drainage tubes, and valves may be required in some patients. If not treated, the disorder can lead to progressive weakness in the arms and legs, loss of hand sensation, and chronic, severe pain. Source: Genetic and Rare Diseases Information Center (GARD), supported by ORDR-NCATS and NHGRI.