Somatosympathetic reflex unilateral sweating and pupillary dilatation in a paraplegic man.

Sympathetic spinal reflex responses to painful stimuli have been studied in experimental animals, but have rarely been demonstrated in human beings. We report the case of a paraplegic man with a high thoracic sensory level to pain, who developed unilateral pupillodilatation and sweating from the head to the midthoracic region as a response to rib fractures below the sensory level. This regional sympathetic reflex response was similar in many ways to that seen in spinally transected animals. Regional sympathetic reflex responses may provide a clinically useful sign of a painful and perhaps dangerous condition which is located below the analgesic level in spinal cord-injured patients.