PROGRESSIVE MUSCULAR ATROPHY
(True atrophic type of PMA, Myelopathic muscular atrophy, Aran-Duchenne atrophy,)
PROGRESSIVE MUSCULAR ATROPHY…| The lesion is chiefly located in the anterior horn cells.Clinically there will be non-symmetrical wasting of the small muscles of the hand which progresses centrally and these wasted muscles will show marked fasciculation which is a very characteristic feature. The interosseous spaces, thenar and hypothenar eminences are hollowed out and ultimately the hand assumes an incomplete claw like deformity called Main-en-griffe.
In course of time lower limbs may also be affected. The last muscle affected is the sternomastoid, so it is called ultimum moriens. The jerks are dull or lost and plantar reflex is flexor in type. There are no sensory or sphincteric changes.The duration of the disease is longer (7-10 years).