Syringomyelia is a chronic disease in which the spinal cord is damaged by the formation of fluid-filled cavities (syrinxes) and the replacement of nervous tissue by scar tissue. The disease, whose cause is unknown, is accompanied by disturbances of motor and sensory function. The spinal cord cavities can extend through a considerable section of the cord. The symptoms depend on which section of the spinal cord is affected. Often the first symptoms are weakness and wasting of muscles of the upper extremities and burning sensations or loss of pain sensation in the lower arms. Syringomyelia usually progresses over many years. No satisfactory treatment has been found, although some physicians advocate surgical drainage of the syrinx.