Hypotonia - is a common finding, which results in defective posture
maintenance and is manifest as a diminished resistance to
passive limb displacements and a delay in the response to such rapid
imposed movements. Limbs are easily displaced by relatively
small force and, when shaken by the examiner, exhibit an increased
range of excursion. When muscles are contracted against
resistance that is then removed, the antagonist muscle fails to check
the movement and compensatory muscular relaxation does not
ensue promptly. This results in rebound movement of the limb ( Holmes'
sign ).
MS Glossary
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