[Infantile spinal amyotrophy with myotonia. Electromyographic study]

An unusual feature was observed in a 7-year-old boy presenting with type II infantile spinal muscular atrophy: percussion myotonia, clinical expression of pseudomyotonic volleys (bizarre high frequency discharge or complex repetitive discharge).

Juvenile-onset bulbospinal muscular atrophy with deafness: Vialetta-van Laere syndrome or Madras-type motor neuron disease?

A girl with rapid-onset, bulbospinal muscular atrophy and deafness is described. The patient's mother and brother showed EMG features consistent with subclinical involvement. T is bulbospinal form of spinal muscular atrophy associated with deafness described by Vialetto and van Laere closely resembles the Madras type of motor neuron disease, also associated with deafness, described by Jagganathan and colleagues.