RIGIDITY
Rigidity is generally associated with severity of involvement. The child with rigidity is characterized by simultaneous and continuous contraction
of both extensors and flexors, with greater power being exerted by the extensors, resulting in a general lack of movement as opposed to
inappropriate or involuntary movement. The limbs of the child with rigidity are virtually locked in full or over-extension, resulting in an arched
position with the back stiff and head and feet at the extremes of the arch.
The child with rigidity such that permits some controlled movement of an extremity has the further complication of involuntary movement of
the opposite extremity (movement of the right arm results in a similar movement of the left).
Various associated complications are generally seen with these children ranging from severe respiratory problems to diminished vision and
hearing, as well as seizure disorder.