Chapter 12 - Movement and cerebellar disorders

Abstract

Many movement disorders involve the cerebellum, yet cerebellar lesions do not always result in ataxic motor syndromes. Chorea involves nonrhythmic, rapid and jerky movements that cannot be stopped intentionally. Athetosis (slow chorea) involves nonrhythmic, writhing and twisting movements, primarily in the distal muscles. Dystonias result in abnormal postures, or jerky, twisting intermittent spasms. Ataxia syndrome (fragile X-associated tremor/ataxia syndrome) includes tremor, ataxia, and dementia. Huntington’s disease usually begins in middle age and worsens, including features of chorea, neuropsychiatric symptoms, and cognitive deterioration. Myoclonus is a brief contraction of muscles that feels like an electric shock. Parkinson’s disease progresses slowly, including resting tremor, rigidity, bradykinesia, gait instability, and postural instability. A tremor is a rhythmic, involuntary movement of various muscle groups, usually in the hands, head, face, vocal cords, trunk, or legs. Cerebellar disorders are related to congenital malformations, hereditary ataxias, and acquired conditions. There is usually impaired muscle coordination. The most common cause of cerebellar disorders is degeneration of the cerebellum due to the use of alcohol. Most movement and cerebellar disorders manifest later in life and progressively worsen.