In article <D22Bsq.Evs at murdoch.acc.Virginia.EDU> tpb9k at galen.med.Virginia.EDU (Thomas P. Bleck) writes:
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>From: tpb9k at galen.med.Virginia.EDU (Thomas P. Bleck)
>Subject: Re: ALS
>Message-ID: <D22Bsq.Evs at murdoch.acc.Virginia.EDU>
>Sender: usenet at murdoch.acc.Virginia.EDU>Organization: University of Virginia
>References: <D22559.BJ1 at murdoch.acc.Virginia.EDU>
>Date: Sun, 8 Jan 1995 01:22:02 GMT
>Lines: 26
>In article <D22559.BJ1 at murdoch.acc.Virginia.EDU>,
>Mallory Leslie McClure <mlm2s at galen.med.Virginia.EDU> wrote:
>>I am a bit confused about ALS (Lou Gehrig's disease.) Isn't
>>ALS a disease which attacks lower motor neurons in the spinal
>>cord? If so, how does it cause bilateral Babinski signs--we
>>were told this in class yesterday and I didn't understand.
>>Please help me to sort this out. Thanks.
>>>>Confused yet again,
>>M.McClure
>>--
>>
>ALS affects both the corticospinal tracts (upper motor neurons)
>and the anterior horn cells. There are less common disorders
>which affect only the corticospinal tracts (e.g., primary
>lateral sclerosis) or only the anterior horn cells.
Mallory,
The involvement of both upper and lower motor neuron pathways explains why
ALS patients have a combination of upper motor neuron signs (e.g.
hyperreflexia and Babinski signs) and lower motor neuron signs (atrophy
and fasciculations) on neurologic examination.
