Template:Upper and lower motor neuron lesions

Clinical findings in upper motor neuron and lower motor neuron injury.

Feature	UMN Deficit	LMN Deficit
Lesion location	Proximal to anterior horn (motor cortex, brainstem, spinal cord)	Anterior horn cell or distal to anterior horn cell (root, plexus, peripheral nerve)
Muscle tone	Increased (spastic paresis)	Decreased (flaccid paralysis)
Muscle bulk	Maintained or mildly atrophic	Severely atrophic
Weakness	In legs, greater in flexors than in extensors; in arms, greater in extensors than in flexors, producing a pyramidal pattern of weakness	Depends on location: uniform spinal cord weakness in all muscle groups of the segment; peripheral nerve weakness of specific muscle groups
Reflexes	Increased	Areflexia
Babinski sign	Positive: upgoing plantar response	Negative
Fasciculations	No	Yes

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