- Key Concepts
- Animation
Lesion to a spinal motor neuron
RESULT: Ipsilateral flaccid paralysis
- Affected muscles lose tone (i.e. are flacid) and reflexes are reduced or lost (spinal or brainstem reflex pathway is interrupted, so reflex cannot be elicited).
- Muscle fibres fasciculate (twitch spontaneously) and later atrophy.
- Flaccid paralysis of muscles occurs on the same side as the lesion, at the level of the lesion.
Lesion to a spinal motor neuron
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RESULT: Ipsilateral flaccid paralysis
- Affected muscles lose tone (i.e. are flacid) and reflexes are reduced or lost (spinal or brainstem reflex pathway is interrupted, so reflex cannot be elicited).
- Muscle fibres fasciculate (twitch spontaneously) and later atrophy.
- Flaccid paralysis of muscles occurs on the same side as the lesion, at the level of the lesion.
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