AMYOTROPHIC LATERAL SCLEROSIS
AMYOTROPHIC LATERAL SCLEROSIS……| The lesion is not only localised to the anterior horn cells but progresses to the pyramidal tracts. Clinically this resembles true atrophic type as given above but the jerks are brisk and the plantar reflex may become extensor. In the upper limb the main features are due to lower motor neurone lesion, i.e., wasting and fasciculation of muscles; but the jerks are brisk and tone is increased, hence this is called Gower’s tonic atrophy. In the lower limbs, however, the features of upper motor neurone lesion will dominate and hence there will be brisk jerk, increased tone,clonus and extensor planter reflex. In this state patient may live for about three years.
A familial form of this variety has been found to be associated with autosomal dominant inheritance with chromosomal abnormality in long arm of chromosome 21.Dementia and Parkinsonism are sometimes associated with this disorder.