Preservation of a certain motoneurone group of the sacral cord in amyotrophic lateral sclerosis: its clinical significance.

Histopathological description of a special nerve cell group of the sacral spinal cord in five cases of amyotrophic lateral sclerosis is presented. Remarkable preservation of this group of neurones (the X group of Onuf) was noted in each case, and this is discussed with particular reference to vesicorectal function, since it is well known that the function of bladder and rectal sphincters is often intact until the latest stage of the illness.