Psychogenic balance disorders: is it a new entity of psychogenic movement disorders?

The various reported psychogenic dyskinesias include tremor, dystonia, myoclonus, gait disorder, Parkinsonism, tics, and chorea. It is not easy to diagnose psychogenic movement disorders, especially in patients with underlying organic disease. We describe three patients with balance and/or posture abnormalities that occur when they stand up, start to move, or halt from walking, although their gaits are normal. One had an underlying unilateral frontal lobe lesion. All patients improved dramatically after receiving a placebo-injection or medication. These abnormal features differ from the previously reported features of astasia without abasia and of psychogenic gait disorders, including recumbent gait. We describe and discuss the patients' unique clinical characteristics.