Choreo-athetotic CP is characterized by involuntary movements, whereas dystonic CP is characterized by slow, strong contractions, which may occur locally or encompass the whole body. Mixed
Mixed cerebral palsy has symptoms of dyskinetic, ataxic and spastic CP appearing simultaneously, each to varying degrees, and both with and without symptoms of each. Mixed CP is the most difficult to treat as it is extremely heterogeneous and sometimes unpredictable in its symptoms and development over the lifespan. Gait Classification
In patients with spastic hemiplegia or diplegia, various gait patterns can be observed, the exact form of which can only be described with the help of complex gait analysis systems. In order to facilitate interdisciplinary communication in the interdisciplinary team between those affected, doctors, physiotherapists and orthotists, a simple description of the gait pattern is useful. J. Rodda and H. K. Graham already described in 2001 how gait patterns of CP patients can be more easily recognized and defined gait types which they compared in a classification. They also described that gait patterns can vary with age. Building on this, the Amsterdam Gait Classification was developed at the free university in Amsterdam, the VU medisch centrum. A special feature of this classification is that it makes different gait patterns very easy to recognize and can be used in CP patients in whom only one leg and both legs are affected. According to the Amsterdam Gait Classification, five gait types are described.
In his doctoral thesis he stated that CP was a result of a problem around the time of birth. He later identified a difficult delivery, a preterm birth and perinatal asphyxia in particular as risk factors. The spastic diplegia form of CP came to be known as Littles disease. At around this time, a German surgeon was also working on cerebral palsy, and distinguished it from polio. In the 1880s British neurologist William Gowers built on Littles work by linking paralysis in newborns to difficult births. He named the problem "birth palsy" and classified birth palsies into two types: peripheral and cerebral.Working in Pennsylvania in the 1880s, Canadian-born physician William Osler (1849–1919) reviewed dozens of CP cases to further classify the disorders by the site of the problems on the body and by the underlying cause. Osler made further observations tying problems around the time of delivery with CP, and concluded that problems causing bleeding inside the brain were likely the root cause. Osler also suspected polioencephalitis as an infectious cause. Through the 1890s, scientists commonly confused CP with polio.Before moving to psychiatry, Austrian neurologist Sigmund Freud (1856–1939) made further refinements to the classification of the disorder. He produced the system still being used today. Freuds system divides the causes of the disorder into problems present at birth, problems that develop during birth, and problems after birth.