Fasciculations masquerading as minipolymyoclonus in bulbospinal muscular atrophy

Abstract

Minipolymyoclonus has been described in both anterior horn cell disorders and central nervous system degenerative conditions. While its etiology remains unclear and speculative, a central generator has been previously proposed. We describe a case of bulbospinal muscular atrophy (Kennedy′s disease), where minipolymyoclonus-like movements corresponded to fasciculations in neurophysiological studies. Our novel finding suggests that the etiologies of minipolymyoclonus in central and peripheral nervous system disorders are distinct, despite outward clinical similarity. The term "minipolyfasciculations" may be more reflective of the underlying process causing minipolymyoclonus-like movements in lower motor neuron disorders.

Keywords

• Bulbospinal muscular atrophy
• EMG-EEG back averaging
• Kennedy′s disease
• minipolymyoclonus
• polyminimyoclonus