Osler's monograph on cerebral palsy helped define this condition. "Osler emphasized the diverse causes of childhood hemiplegia. Osler classified his patients with nonprogressive upper motor neuron dysfunction according to the distribution of their weakness (hemiplegia, diplegia, and paraplegia) and separated the children with congenital dysfunction from those whose weakness was acquired later in childhood. The monograph contains numerous case descriptions and emphasizes signs, symptoms, and etiology" (Ashwal, Founders of Child Neurology, p. 329; see also pp. 330-32).
See also Longo, L.D. & Ashwal, S. "William Osler, Sigmund Freud and the evolution of ideas concerning cerebral palsy," J. Hist. Neurosci., 2 (1993) 255-82.