Juvenile lower cervical spinal muscular atrophy in Taiwan: report of 27 Chinese cases.

Clinical observations as well as electromyographic studies were carried out on 27 Taiwanese Chinese patients deemed to be suffering from a rare, unique and self-limiting variant of lower motor neuron disease affecting the upper limbs with juvenile onset and a marked male preponderance. The results agree with previous descriptions of the disease except for the higher incidence of triceps affection. The term 'juvenile lower cervical spinal muscular atrophy', which describes the disease more accurately, is being proposed. The geographic relevance is discussed.