01 Definition Se qxd

published discussion by conceding to the President of the

Obstetrical Society of London that for every ‘one (case) that

depended on abnormal or premature labour there were

twenty or more from other causes incidental to later life’.

Sarah McNutt, an American physician, continued to raise the

profile of the risks of long-term disability arising from birth

trauma (McNutt 1885). Notably, the American Neurological

Association admitted her as their first female member; but

the content of her lectures apparently made her unpopular

with some eminent obstetricians whilst she was on a tour in

the UK (Ingram 1984). 

At the time he was resident in America, the eminent Canadian

William Osler published articles in 1886 and 1888 before his

more notable monograph was published in London in 1889.

‘The Cerebral Palsies of Children’ comprehensively described

his study of a case series of 151 patients (Osler 1889). Osler

acknowledged the contributions from his German, French,

English, and American colleagues and stated that he would

‘for clearness and convenience adhere to custom and classify

cases according to the distribution of the paralysis, whether

hemiplegic, diplegic or paraplegic’. In fact, he classified his

cases into the three categories but used the terms: (1) infan-

tile hemiplegia; (2) bilateral spastic hemiplegia; and (3)

spastic paraplegia. Osler references the synonym spastic

diplegia for bilateral spastic hemiplegia to Samuel Gee at St

Bartholomew’s Hospital in London. William Osler later moved

from Pennsylvania to become Regius Professor of Medicine

at the University of Oxford and was knighted in the UK for his

contributions to medicine. 

In the year following Osler’s seminal book, the neurolo-

gists Sachs and Peterson published their series of 140 cases

(Sachs and Peterson 1890). They contrasted the comprehen-

sive understanding that had then been achieved regarding

the clinical symptoms and pathology of poliomyelitis with

the dearth of understanding about CP. Sachs and Peterson

followed the convention of the time by using the same classi-

fication system as Osler: hemiplegic, diplegic, or paraplegic.

Where possible, they investigated aetiology using post-

mortem examinations but concluded that any of the three

clinical presentations could result from a variety of causes.

Despite this lack of correlation they advocated that classifica-

tion should include ‘special reference to the pathology of the

disease’. 

Sigmund Freud was of the opposite opinion (Freud 1893).

Despite his background in neuropathology, he advocated

classifying CP using only clinical findings. Freud recognized

that, even with post-mortem examination, the pathological

findings resulted from a combination of the initial lesion and

repair process and, therefore, were only partially related to

the clinical manifestation. His classification system combined

previously separate categories under the single term ‘diple-

gia’ for all bilateral disorders, as distinct from hemiplegia.

The term diplegia was used to describe generalized rigidity

of cerebral origin, paraplegic rigidity, double spastic hemi-

plegia, generalized congenital chorea, and generalized

athetosis. Athetosis had already been described, initially by

Hammond, as involuntary writhing movements in adults

affected by hemiplegia (Hammond 1871), and it would later

be more clearly differentiated from other movement disor-

ders by Gowers (1876). Freud’s observations regarding aeti-

ology identified three groups of causal factors: (1) maternal

and idiopathic congenital; (2) perinatal; and (3) post-natal

causes. He noted that it was difficult to know whether later

problems resulted from birth trauma, as described by Little,

or whether in fact there were predisposing factors that may

have caused these infants to have difficult births. He thought

the task of separating congenital from acquired cases impos-

sible in some cases and generally unhelpful. Freud was aware

that children with ataxic symptoms might require a separate

group, as became the case after the work of Batten (1903),

but at the time of his writing he had not seen enough cases of

non-progressive ataxia to be sure. 

Freud lost interest in CP and instead focused on his study

of psychoanalysis (Accardo 2004). Nevertheless, his influ-

ence was such that his lasting statements regarding the futili-

ty of attempting to associate clinical syndromes with

neuropathology may have predisposed to the dearth of research

about CP during the first half of the twentieth century. Also,

at that time, poliomyelitis and tuberculosis were more com-

mon causes of disability and, therefore, attracted greater

attention from medical researchers.

From 1900 to 2000

In the early 1920s, some 30 years after Freud’s comments, an

American orthopaedic surgeon made the next major contri-

bution to our understanding of CP (noted by Mac Keith and

Polani 1959). Winthrop Phelps pioneered modern approach-

es to the physical management of children with CP advocat-

ing physical therapy, orthoses, and nerve blocks. In a later

article Phelps identified his four treatment goals: locomo-

tion, self-help, speech, and general appearance (Phelps

1941). His approach to surgery was conservative. Phelps

acknowledged the need for a neurological classification sys-

tem for diagnostic purposes but preferred to use his own

classification system as a basis for treatment. He proposed

that classification should be made on a functional basis

including both mental and physical ability, and that a social

assessment should precede treatment. Phelps grouped all

movement disorders under the term dyskinesia, and used

spasticity, athetosis, overflow or synkinesia, incoordination

or ataxia, and tremor as sub-categories. He noted that these

five varieties rarely occurred in pure form. Phelps helped to

found the American Academy for Cerebral Palsy in 1947 and

was elected its first president. The Academy’s mission remains

‘to foster and stimulate professional education, research,

and interest in the understanding of these conditions and in

improving the care and rehabilitation of affected persons’

(American Academy for Cerebral Palsy and Developmental

Medicine 2005).

American neurologist Myer Perlstein recognized the pre-

vailing confusion regarding classification of CP and con-

tributed a lucid account of the various systems that existed in

the 1940s and 1950s (Perlstein 1952). He recounted methods

for classifying children according to the anatomical site of

the brain lesion, clinical symptoms, degree of muscle tone,

severity of involvement, and aetiology. Thus, he suggested

that a modular description using components from each cat-

egory can be assembled. Minear conducted a survey with the

members of the American Academy for Cerebral Palsy in 1953

and published the resulting classification system based on

their majority opinion (Minear 1956). He defined CP simply

as any ‘symptom complex’ arising from non-progressive

brain lesions. Minear’s system is similar to Perlstein’s in that

it is more of a comprehensive listing of all clinical symptoms

4

Definition and Classification of CP

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