Rigid and Akinetic Forms of Huntington's Chorea

William Osler39considered Huntington's27original description of chronic chorea a model of cogent observation and concise presentation. The classic paper set forth the characteristic movement disorder and mental changes and implied a dominant heredity which was ultimately proven correct by Entres18and others. In addition, hypotonia was soon added as a characteristic if not constant finding in this disorder which set it apart from the other heredodegenerative diseases of the basal ganglia. Davenport,12in 1916, noted individual and familial variations in the age of onset of the chorea, as well as the delayed onset or complete absence of dementia in some cases. His concept of different biotypes was more fully developed by the Continental neurologists to include a variety of hitherto unrelated neurologic and psychiatric phenomena into a broadened concept of Huntington's disease. One outgrowth of the biotype theory—an enhanced appreciation of the variations of tone