THE ISSUE of trauma in the production or precipitation of amyotrophic lateral sclerosis is difficult to assess, as it is in all nervous diseases. Experience with 2 patients in whom symptoms of the disease appeared to follow the use of a pneumatic drill raised the problem of whether repeated trauma might play a role in precipitation of the disease, and for this reason we report the cases in question.
REPORT OF CASES
Case 1.
—Amyotrophic lateral sclerosis in a 63 year old man who had worked with a pneumatic hand drill for nine months, symptoms appearing in the eighth month of its use; signs of anterior horn cell disease confined largely to the cervical portion of the spinal cord.
History.
—E. H., a 63 year old Armenian man, was admitted to the Jefferson Hospital on May 5, 1947, with the complaint of weakness and twitching of the arms. Twenty months