Rigidity is characterized by increased resistance throughout the movement involving flexor and extensor muscles, which is different from spasticity involving single muscle compartment. Mainly 2 types of rigidity are described: Lead-pipe rigidity, which is uniform throughout the movement and Cogwheel rigidity, which is characterized by rhythmic interruption of the resistance, producing a wheel-like effect.
See also Hypertonia Movement disorder Parkinsonism
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