Sensory Loss

Authors: Flaherty, Alice W.; Rost, Natalia S.

Title: Massachusetts General Hospital Handbook of Neurology, The, 2nd Edition

Copyright 2007 Lippincott Williams & Wilkins

> Table of Contents > Adult Neurology > Sensory Loss

Sensory Loss

A. H&P

Pts. use numbness to mean everything from tingling to paralysis. Ask about pain, paresthesias, hyperpathia. Look for dermatomal or individual nerve distributions, distal vs. proximal differences, spinal cord level, spared modalities, graphesthesia, stereognosis, neglect to bilateral simultaneous stimulation. Associated signs: weakness, skin changes, cranial nerve abnormalities. For hysterical numbness, see p. 104.

B. DDx

• 1. Mononeuropathies and monoradiculopathies: Usually trauma or compression; sometimes vasculopathy (e.g., in DM), zoster, leprosy.

• 2. Symmetric distal sensory loss ( stocking glove ): Usually polyneuropathy from chronic illness or toxin.

• 3. Hemianesthesia: Damage to sensory cortex, thalamus, white matter.

• 4. Dissociated or crossed sensory deficits: Often from brainstem or spinal cord lesions; generally with other neurological deficits.

  • a. Brainstem syndromes: See brainstem stroke syndromes, p. 28.

  • b. Posterior column: Ipsilateral decreased position, vibration, stereognosis (but often bilateral involvement).

  • c. Hemisection (Brown-Sequard syndrome): Ipsilateral decreased position and vibration; contralateral decreased pain and temperature. Little change in fine touch. Upper motor neuron signs beneath level of lesion.

  • d. Central cord syndrome: Usually from syringomyelia: cavity near the central canal. Often begins cervically, with cape-like loss of

    P.112

    
    pain and temperature sensation; then gradual spasticity and loss of light touch, sometimes facial or tongue weakness.

  • e. Suspended sensory loss: Isolated numb band on thorax. Specific for spinal cord lesions.

• 5. Paresthesias: Peripheral neuropathy or compression; peripheral vascular dz; spinal cord dz; metabolic disturbance, e.g., hypocalcemia or respiratory alkalosis; postherpetic neuralgia .