Dystonia

Abstract

This chapter presents a review of the literature for falls and abnormalities of balance and gait in isolated dystonia syndromes. Balance appears to be relatively preserved in primary and focal dystonias, except when postural abnormalities significantly displace the center of gravity of the body. Gait can be affected by abnormal dystonic movements and limb deformities, and is commonly abnormal in generalized dystonia. Impairment of gait can also be seen in patients with cervical dystonia when it results in abnormal posturing, and severe cases of blepharospasm leading to functional blindness. Gait abnormalities have also been described in dystonia associated with dopa-responsive dystonia (DRD) and Wilson disease. The data on dystonia and falls are scarce but it has been described as one of the main symptoms of DRD. Local field potential recordings point to abnormal synchronization activity in the pallidum as the main pathophysiologic finding. Cerebellar dysfunction has been reported in patients with primary dystonia and some forms of focal dystonia. While contradictory data have been published on the association between vestibular dysfunction and cervical dystonia, abnormal neck proprioception appears to be present in the latter. Treatment of the dystonia can improve balance and gait, as well as reduce the frequency of falls.

Keywords: dystonia; falls; gait; vestibular system.