Hypoesthesia is a decreased or diminished sensitivity to cutaneous stimuli, including touch, temperature, or pain. It can be partial or localized, affecting one or multiple dermatomes, and may result from peripheral nerve lesions, spinal cord disorders, or central nervous system pathology.

Pathophysiology

• Peripheral nerve injury: Trauma, compression, or neuropathy reduces sensory transmission along affected nerves.

• Spinal cord lesions: Hemisection (Brown-Séquard syndrome), transverse myelitis, or demyelination can impair sensory input from specific dermatomes.

• Central lesions: Stroke, tumor, or cortical damage may produce contralateral or segmental hypoesthesia.

• Metabolic/systemic conditions: Diabetes, vitamin deficiencies, or toxin exposure can impair peripheral sensory nerve function.

Examination Technique

1. Patient positioning: Seated or lying comfortably.

2. Instruction: Ask the patient to close their eyes to prevent visual cues.

3. Testing: Lightly touch the skin with a cotton wisp, blunt object, or temperature/pain probe.

4. Assessment: Ask the patient to identify the location, type, and intensity of the stimulus.

5. Observation: In patients with limited communication skills, observe withdrawal reflexes, flinching, or facial expression.

6. Documentation: Map the areas of diminished sensation and note laterality, extent, and severity.

Clinical Features

Differential Diagnosis

Pediatric considerations

• Children may have difficulty describing reduced sensation.

• Observation of withdrawal or facial response is essential.

• Gentle handling is important to avoid fear or inaccurate results.

Geriatric considerations

• Older adults may have subtle, slowly progressive hypoesthesia due to peripheral neuropathy or stroke.

• Sensory mapping helps prevent injuries and assess fall risk.

Limitations

• Requires patient cooperation for accurate localization.

• Subtle deficits may need electrophysiological studies or imaging.

• Cannot reliably distinguish central vs. peripheral lesions without adjunctive testing.

Patient counseling

• Explain the purpose of sensory testing and expected responses.

• Advise patients to protect areas with decreased sensation to prevent burns, cuts, or trauma.

• Recommend follow-up evaluation if progressive sensory loss is noted.

Conclusion

Hypoesthesia is an important neurological sign indicating diminished sensory input. Careful clinical assessment can localize lesions, monitor progression, and guide management of underlying neurological or systemic disorders.

References

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2. McCance KL, Huether SE, Brashers VL, Rote NS. Pathophysiology: The Biologic Basis for Disease in Adults and Children. 7th ed. Maryland Heights, MO: Mosby Elsevier; 2010.

3. Colyar MR. Well-Child Assessment for Primary Care Providers. Philadelphia, PA: F.A. Davis; 2003.

4. Tintinalli JE, Stapczynski JS, Ma OJ, Yealy DM. Tintinalli’s Emergency Medicine: A Comprehensive Study Guide. 9th ed. New York, NY: McGraw-Hill; 2020.