Diaphragmatic flutter, the moving umbilicus syndrome, and "belly dancer's" dyskinesia.

Five patients presenting with focal abnormal involuntary movements of the abdominal wall are described. One was shown to have diaphragmatic flutter, which may represent a variant of the palatal myoclonus syndrome. The other four had writhing movements and contractions of the abdominal wall at frequencies of approximately 30 per minute. In two of the latter cases, these abdominal movements were profoundly influenced by respiratory manoeuvres. They were quite unlike the movements of spinal myoclonus or axial torsion dystonia. None of the patients were taking drugs that might have provoked their abnormal movements, or had any other evidence of neurological deficit. No cause was established in any of the cases.