Osteopathic Medical theory holds that the fluid action
of the embryologic organism, through its various stages
of development, will help to shape its genetically
William G. Sutherland, D.O., a student of A.T. Still, M.D., theorized and developed
the concept of "Cranial Osteopathy".
He spoke of the "fluid tide"
rhythmic movement of the
cerebrospinal fluid (CSF).