Complex movement behaviour and progression of Huntington's disease.

Instrumental measurement of complex motion sequences with a peg insertion paradigm reflects impairment in patients with Huntington's disease (HD). Objectives were to study progress of HD symptoms and peg insertion results in 39 HD patients without symptomatic drug treatment over an interval of 3 years. Assessments were at baseline and 3 years later. Unified Huntington's Disease Rating Scale (UHDRS) total score, computed arm score and the specific rating outcomes for bradykinesia, chorea, dystonia and oculomotor symptoms significantly increased over a 3-year period. Motor test outcomes significantly worsened. Cognitive scores did not change significantly, but were significantly related to the peg insertion outcomes and to the various UHDRS rating results at both assessments. Peg insertion scores are nonspecific diagnostic marker for progress in HD. Peg insertion particularly reflects motor impairment and additionally higher cognitive and executive dysfunction. These higher cognitive functions are associated with frontostriatal pathology in HD. Our study results suggest that our motor test reflects these emerging deficits of higher cognitive and motor function abilities in HD. We conclude, that instrumental assessment of complex movement sequences is an additional simple method to follow impairment in HD patients in addition to clinical rating.