MULTIFOCAL MOTOR NEUROPATHY
Multifocal motor neuropathy (MMN) resembles amyotrophic lateral sclerosis (ALS), producing progressive muscular weakness & atrophy in the hands, arms, and shoulder girdle. Unlike ALS, MMN does not cause upper motor neuron disease. Both conditions damage anterior horn cells, causing muscular fasciculations (see video). This patient had chronic lymphocytic leukemia; the MMN was considered to be a paraneoplastic condition.