Spinal Nerve Lesions Flashcards
Peripheral nerve lesion (LMN)
Motor and sensory deficits
Dorsal root lesion (LMN)
Sensory deficits only
Ventral root lesion
Motor deficit only
Ventral horn lesion (LMN)
Motor deficits only
LMN lesion signs
(Ipsilateral muscles) Areflexia Flaccid paralysis Muscle wasting Fasciculation
UMN lesion signs
(Ipsilateral movements below spinal cord lesion) Paresis Spastic paralysis Little wasting (LMN still innervating) Exaggerated DTR Babinski sign
Lesion in dorsal column
Ipsilateral loss of vibration, position, two point discrimination, deep touch
Lesion in corticospinal tract
Ipsilateral inferior UMN symptoms
Lesion in spinothalamic tract
Contralateral loss of pain and temperature
Lesion in autonomics
Ipsilateral miosis, ptosis, anhidrosis, enophthalmos
Lesion in spinal motor neurons
Ipsilateral LMN
Brown-Sequard Syndrome
Spinal cord hemisection
Ipsilateral dorsal column and corticospinal signs
Contralateral spinothalamic signs
Bilateral loss of pain and thermal sense (spinothalamic fibers cross in anterior white commissure)
Syringomyelia
Lesion around central canal
First sign is disruption of anterior white commissure (spinothalamic tract)–cape-like distribution
As lesion grows it impacts motor neurons–axial then extremities
Anterior spinal artery syndrome
Occlusion of ASA
Affects corticospinal and spinothalamic tracts
LMN symptoms
CN VII lesion (UMN)
Contralateral lower facial paralysis