[Alterations of gait parameters under external cueing in schizophrenic patients: a switch study].

Schizophrenic disorders as well as neuroleptic treatment can affect locomotion. The study assessed the influence of neuroleptic treatment on externally triggered gait on a treadmill at three different velocities via ultrasonic topometric gait analysis. Spatial and temporal gait parameters were assessed in two groups of schizophrenic patients either under treatment with conventional neuroleptics (n = 12) or without neuroleptic treatment (n = 10) and re-assessed after treatment change to the atypical neuroleptic olanzapine in a repeated measures design. After switch from conventional neuroleptics to olanzapine patients showed an increase of step length and decrease of cadence at the low (p </= 0.01) and the intermediately low treadmill velocity (p </= 0.05), whereas the parameters remained stable at the normal gait velocity. Significant differences between the untreated state and treatment with olanzapine were not detectable. We conclude that conventional neuroleptic treatment impairs the regulation of gait parameters and that this effect can be reversed at slow gait velocities by external stimulation via treadmill walking.