Supplementary Material for: Belly Dancer’s Dyskinesia: 3 Cases of a Rare Entity

Involuntary, undulating, or circular movements of abdominal wall muscles are a rare condition descriptively termed belly dancer syndrome or belly dancer’s dyskinesia. Differential diagnoses range from cerebral, spinal, peripheral, hormonal/drug-induced effects to local or even unknown/idiopathic and functional/psychogenic causes. Thorough diagnostic work-up is mandatory and therapeutic options depend on etiology and include surgical approaches and symptomatic treatment. We present 3 cases of belly dancer’s dyskinesia, in which differential diagnostic work-up did not uncover known etiologies for this movement disorder. Strikingly, 2 patients manifested vitamin B12 deficiency while 1 case showed values close to the lower limit of normal. While relevance of vitamin B12 levels remains elusive, all patients improved substantially following a combined therapeutic approach of clonazepam treatment and vitamin B12 supplementation.