Presence of Ideomotor Apraxia in Stroke Patients with Pusher Syndrome

[Purpose] Pusher syndrome, which is a disorder of postural balance that occurs in hemiparetic stroke patients, is characterized by a particular tendency to strongly push toward the hemiparetic side. The purpose of this study was to investigate whether stroke patients with pusher syndrome have ideomotor apraxic behavior. [Subjects] Fifteen stroke patients with pusher syndrome and 31 stroke patients without pusher syndrome were recruited. [Methods] All subjects were tested with two tests assessing ideomotor apraxia of movements of the upper and lower limbs. Each test included 12 items of movements, which required the subjects to reproduce movements by imitation after presentation. [Results] Patients with pusher syndrome had significantly lower ideomotor apraxia scores in all of the upper and lower limbs than patients without pusher syndrome. A significant difference was observed between the two groups in the existence of neglect. [Conclusion] We found that patients with pusher syndrome had more severe apraxic disorder in all of the upper and lower limbs than patients without pusher syndrome. Pusher syndrome may be attributable to disabilities in motor planning and execution, which are required to compensate for the partial damage to the postural control system.