Abstract
Diffuse white matter changes on magnetic resonance imaging (MRI) have been a consistent
feature in some children with the "pure" form of congenital muscular dystrophy (CMD)
in which there are no structural changes in the brain or severe mental retardation.
The aim of this study was to assess fine motor and perceptuo-motor abilities in children
with CMD with and without MRI changes.
Twenty-two children with "pure" CMD were investigated with a standard neurological
examination and a battery of tests (Manual dexterity from the Movement ABC, test of
visual-motor integration, Zurich Neuromotor test) which have already been used to
detect minor neurological signs related to white matter changes. The cohort was then
divided in two groups for analysis depending on the presence or the absence of diffuse
white matter changes. A significant difference was found for all the tests between
the group of the CMD children with normal MRI and the group with diffuse white matter
changes. The manual dexterity and the Zurich Neuromotor tests showed a greater sensitivity
than the test of visual-motor integration, which had some false negatives. It is of
interest that in the group with diffuse white matter changes the presence of contractures
or weakness did not seem to affect the quality of the performance; all these children
scored abnormally on the test, irrespective of the severity or the extent of contractures
and weakness. In contrast, in children with normal MRI severe contractures and weakness
did affect the performances.
Our results demonstrate that perceptuo-motor difficulties and minor neurological soft
signs are a consistent feature in CMD children with diffuse MRI changes but not with
normal MRI. We suggest that a more detailed neurological examination for the detection
of these abnormalities may lead to more specific supportive help for everyday life
and school performances in these children. The concordance of our results with MRI
findings would also suggest that these tests might provide an additional help in identifying
the different subgroups of CMD.
Key words
Congenital muscular dystrophy - Brain - Merosin - MRI
