Physical examination maneuver

Physical Exam

Cranial Nerve XII

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How to Perform

Inspect the tongue at rest on the floor of the mouth for atrophy or fasciculations, then ask the patient to protrude it and observe for deviation of the tongue to one side. Test tongue strength by having the patient push the tongue against the inside of each cheek against your finger.

How to Interpret

Showing 1 of 4 findings

Stroke

Tongue deviation toward the weak (hemiparetic) side on protrusion
Rule in
HelpfulDerived CI
Rule out
Not helpfulDerived CI
Evidence:ModerateResearch in progress

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Related Systems / Regions

Head, Eyes, Ears, Nose, ThroatNeurological

Related Diagnoses

Hypoglossal Nerve PalsyStroke

Related Chief Complaints

Difficulty SwallowingSlurred SpeechTongue DeviationTongue Weakness

References

Research in progress on one or more findings above; ratings may change.

  • Galeazzi L, Holzman J, Mondoloni M, Rochefort J. Lingual fasciculation: a point of call for the diagnosis of amyotrophic lateral sclerosis. Clin Case Rep. 2023;11(6):e7560. doi:10.1002/ccr3.7560. PMID: 37334341. PMCID: PMC10276246 (open access).
  • Umapathi T, Venketasubramanian N, Leck KJ, Tan CB, Lee WL, Tjia H. Tongue deviation in acute ischaemic stroke: a study of supranuclear twelfth cranial nerve palsy in 300 stroke patients. Cerebrovasc Dis. 2000;10(6):462-465. doi:10.1159/000016108. PMID 11070377.
  • Bickley LS, Szilagyi PG, Hoffman RM, Soriano RP. Bates' Guide to Physical Examination and History Taking. 13th ed. Philadelphia, PA: Wolters Kluwer; 2021.
  • Swartz MH. Textbook of Physical Diagnosis: History and Examination. 9th ed. Philadelphia, PA: Elsevier; 2025.

Research last updated September 10, 2026.