Introduction

We have all experienced physiological myoclonus in the form of hiccups, sneezes or sleep starts (hypnic jerks). Myoclonus may sometimes be generated by a normal brain under toxic or metabolic stress.1 Pathological myoclonus may occur in many neurological diseases, such as epilepsy, dementia or movement disorder. Subtle jerks may pass unrecognised, for example, teenagers with juvenile myoclonic epilepsy may describe themselves as ‘clumsy’ due to jerks in the morning. Myoclonus in the older people may be misdiagnosed as unexplained falls or a ‘bouncing gait’ (figure 1).

Myoclonus is transient in a quarter of cases, responding to treatment of the underlying cause. However, its successful management depends on correctly diagnosing the aetiology.

With such a wide range of causes, the clinical assessment of pathological myoclonus in adults requires a systematic approach. This review aims to facilitate its management through describing an approach to the clinical review, differential diagnosis and optimal treatment of patients with myoclonus.