text: [Evolution of locomotion disorders in Huntington's disease].
  Locomotion disorders are important in Huntington's disease (HD). Although the rates of evolution of motor, functional or cognitive aspects of HD have been studied, the evolution of locomotion disorders in early stages of the disease remains unknown. To determine the rate of evolution of the HD-associated gait and gait initiation disorders and their correlates. Eighteen HD patients were recorded with a minimum interevaluation interval of one year. Akinesia was studied by evaluating the anticipatory postural adjustment (APA) phase preceding the first step. We also evaluated gait speed, stride time and stride length. We observed an alteration in the APA phase, whose evolution was correlated with that of akinesia. We also observed a decrease in gait speed, which was due both to an increase in stride time and a decrease in stride length. Stride-to-stride variability did not worsen between both evaluations. A worsening in both gait initiation and gait performance was observed in HD. Initial weak functional capacity and more severe motor impairment seem to be associated with a faster progression of locomotion parameters in these mildly impaired HD patients.