Posttraumatic syringomyelia can be a subtle entity initially. Its variety of clinical features, awareness of the early clinical manifestations is a necessary adjunct in preventing disabling sequelae, Because the clinical manifestations of posttraumatic syringomyelia are variable and subtle, physicians who care for patients with spinal cord injury should be aware of the sings and symptoms of posttraumatic syringomyelia. Pain and autonomic symptoms should alert the physician to the possibility of this entity as initial symptoms. It can be suggested that as the location of syringmyelia is near the center of the spinal cord of the intermediolateral cell column and lateral reticulospinal tract, which related to control of the sympathetic nervous system, central cysts of the spinal cord can be expected to interfere with sympathetic function. We examined the eight spinal cord injured patients for the newly developed problems of aggravation of pain, orthostatic hypotension, excessive sweating, anhydrosis, autonomic hyperreflexia, aggravation of spasticity and paroxysmal episodes of unconsciousness following stable period of fixed neurologic and medical state after traumatic spinal cord injury. In three of these 8 patients, magnetic resonance imaging confirmed the presence of posttaumatic syringomyelia.