Although infantile muscular atrophy has been recognized for about 70 years, a comprehensive description of its variable clinical course is generally wanting. The purpose of the present article is to call attention to the wide spectrum of its onset and severity and to correlate these features with the pathological changes.
Historical
In 1891 Werdnig1 described 2 brothers who exhibited toward the end of their first year a progressive weakness beginning in the pelvic and thigh muscles. One brother was able to stand before the weakness was obvious. Soon after the weakness appeared in the legs, tremor throughout active movement was noted in their arms and hands. One child died from pertussis at the age of 3 years. Autopsy, which did not include the brain, showed a bilateral, symmetrical loss of anterior horn cells and a glial proliferation in these zones. Clarke's column was intact as were all the tracts