A) B/C the primary lesion sites would actually be the LMN and UMN cell bodies, the degeneration of the pyramidal tract is a consequence, so I'm not sure if C is right
B) A
C) B
D) D/E/F
E) C/D/E/F
oops..i didnt understand the question before ..
here are my answers..
ALS...B and C
Syringomyelia...A
poliomyelitis...B
Tertiary syphilis..D and E
pernicious anemia..D and E
A) Amyotrophic Lateral Sclerosis = B and C
B) Syringomyelia = A
C) Poliomyelitis = B
D) Tertiary syphilis = Tabes dorsalis D and E
E) Pernicious anemia = C, D & E
I have a question: but if in both tabes dorsalis and pernicious anemia there are hyporeflexia and hypotonicity (together with the other classic signs of posterior cordonal injury)... then shouldn't there be involvement of the posterior roots as well? otherwise where would Ia afferent fibers from neuromuscluar spindles be interrupted? :redcheeks;
(don't know if I expressed myself clearly)
Yup, you are right...but the lesion is not in F though:
"Tabes dorsalis is caused by syphilis. The organism causes a selective destruction of nerve fibers at the point of entrance of the posterior root into the spinal cord, especially in the lower thoracic and lumbosacral regions "
It can have both, it depends on whether the mostly involved are the posterior or the lateral tracts of the spinal chord: in the first case there is segmental hyporreflexia because of afferent fibers interruption (it becomes evident only if the lesion is quite extended in length), in the latter sub-segmental hyperreflexia, because of pyramidal syndrome.
At least, that's what i think...
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