Sensory Localization Flashcards
Site of Lesion: Peripheral Nerve
Findings: Loss of LT, T, PP, and proprioception, in the influenced aria, associated weakness in the muscles innervated by that nerve.
Other neurologic abnormalities: distal muscle weakness, atrophy, areflexia.
Examples: peroneal neuropathy, median and ulnar neuropathies.
Site of lesion: Root
Findings: Loss of all sensory modalities in a dermatomal distribution.
Other neurologic abnormalities: Weakness in a myotomal distribution, atrophy, segmental hyporeflexia.
Examples: L5 radiculopathy, cervical radiculopathy.
Site of lesion: plexus
Findings: sensory loss in the distribution of two or more peripheral nerves.
Other neurologic abnormalities: muscle weakness that cannot be localized to a single nerve or root.
Examples: bracial plexopathy due to trauma, inflammation, infiltration, etc.
Site of lesion: spinal cord
Findings: Sensory level: bilateral loss of all sensory modalities. Sensory dissociation. Contralateral hypestheisa and ipsilateral loss of proprioception (Brown Sequard syndrome), proprioceptive loss and corticospinal tract involvement. Saddle anesthesia.
Other neurologic abnormalities: paraplegia, tetraplegia, initially areflexia and then hyperreflexia below the lesion, Babinski sign.
Examples: myelopahty, central cord syndromr, brown sequard syndrome, subacute combined degeneration.
Site of lesion: Brainstem
Findings: ipsilateral facial numbness and contralateral body numbness.
Other neurologic abnormalities: alternating hemiplegia, cranial nerve findings, INO, ataxia.
Examples: Posterior circulation strokes, tumor.
Site of lesion: Thalamus
Findings: hemibody anesthesia.
Other neurologic abnormalities: may have motor findings.
Examples: lacunar strokes, hemorrhage.
Site of lesion: Posterior limb of internal capsule
Findings: hemibody anesthesia.
Other neurologic abnormalities: hemiplegia.
Examples: lacunar stroke, hemorrhage, tumor.
Site of lesion: Cortex
Findings: All modalities affected on contralateral side.
Other neurologic abnormalities: sensory neglect, agraphia.
Examples: parietal strokes, hemorrhage, AVM
Site of lesion: Psychogenic
Findings: hyperesthesia for one modality in one area with anesthesia for another modality in the same area, changing sensory findings, nonphysiologic sensory level changes
