Multifocal motor neuropathy

Multifocal motor neuropathy (MMN) is a unique disorder characterized by slowly progressive, asymmetric, distal and upper limb predominant weakness without significant sensory abnormalities. Electrophysiology is crucial to the diagnosis, revealing the hallmark partial conduction block. MMN is considered immune mediated due to the association with anti-GM1 antibodies and the response to immunomodulatory treatment. It is paramount to recognize MMN from other motor neuronopathies or peripheral neuropathies as it is treatable. Advances in pathogenesis, clinical features, electrophysiology, diagnostic studies and treatment are reviewed. References for this review were identified from literature search on Pubmed limited to dates from 1988 to 2011. Papers were selected if relevant to the review topic and published in English.