Teaching Neuro Images : Spinocerebellar ataxia type 3 presenting with a cock-walk gait phenotype

A 22-year-old woman presented with a 4-year history of progressive gait disturbance and slurred speech. Examination disclosed ataxia, nystagmus, pyramidal signs, bradykinesia, and feet dystonia with a cock-walk gait pattern (video at [Neurology.org][1]). There was no weakness of ankle dorsiflexion or plantar flexion. Family history was remarkable for ataxia. MRI showed mild pontocerebellar atrophy (figure). Genetic testing confirmed spinocerebellar ataxia type 3 (SCA3; 34/77 alleles). There were poor responses to levodopa, anticholinergic drugs, and botulinum toxin. [1]: http://neurology.org/lookup/doi/10.1212/WNL.0000000000004497