NIHSS Limb Ataxia 4 — Questions and Answers
Question 1: A patient with a right cerebellar stroke scores 1 on limb ataxia (right arm ataxic only). Two hours later, re-examination shows the right leg is now also ataxic. What is the updated score?
- 0
- 1
- 2 (Correct answer)
- 3
Correct answer: 2
With both right arm and right leg now demonstrating ataxia, the updated score is 2.
Question 2: In the NIHSS, which finger-to-nose maneuver finding specifically triggers a score of 1 rather than 0 for limb ataxia?
- Slight tremor at rest during the task
- Definite dysmetria out of proportion to weakness (Correct answer)
- Mild reduction in speed of movement only
- Any involuntary movement during testing
Correct answer: Definite dysmetria out of proportion to weakness
A score of 1 requires definite ataxia (dysmetria) that is out of proportion to any existing motor weakness.
Question 3: A patient with bilateral arm weakness (2/5) shows incoordination during finger-nose-finger testing. The examiner is unsure whether the incoordination is from weakness or true ataxia. What should be scored?
- Score 2 — bilateral ataxia assumed
- Score 1 — assume at least one limb is ataxic
- Score 0 — ataxia cannot be confirmed as out of proportion to weakness (Correct answer)
- Score UN — bilateral weakness makes testing impossible
Correct answer: Score 0 — ataxia cannot be confirmed as out of proportion to weakness
When incoordination cannot be separated from weakness, the NIHSS convention is to score 0 (no confirmed ataxia).
Question 4: A 70-year-old patient with a known stroke has a prior history of Friedreich's ataxia. Limb ataxia is observed on NIHSS testing. How should the examiner handle this?
- Score the ataxia normally as it is observed during testing (Correct answer)
- Score 0 because pre-existing ataxia is excluded
- Score UN because the origin of ataxia cannot be determined
- Administer an MRI before scoring
Correct answer: Score the ataxia normally as it is observed during testing
The NIHSS scores what is observed at examination; pre-existing conditions are noted but the item is still scored based on current findings.
Question 5: Which of the following most accurately describes the purpose of the limb ataxia item within the broader NIHSS framework?
- To quantify upper motor neuron weakness
- To detect posterior circulation or cerebellar involvement in stroke (Correct answer)
- To assess fine motor speed for cortical function
- To evaluate proprioceptive loss from spinal cord injury
Correct answer: To detect posterior circulation or cerebellar involvement in stroke
Limb ataxia on the NIHSS specifically captures cerebellar or posterior circulation dysfunction that other items may miss.
Question 6: A nurse practitioner documents limb ataxia as 'UN' for both arms after a bilateral arm amputation. Is this correct?
- No — score should be 0 since no ataxia is seen
- No — score should be 2 since both limbs are affected
- Yes — limbs absent due to amputation are scored untestable (Correct answer)
- Yes — but only if the amputation is above the elbow
Correct answer: Yes — limbs absent due to amputation are scored untestable
Absent limbs (from amputation or other causes) cannot be tested and are appropriately scored UN.
Question 7: What is the maximum possible score a patient can receive on the NIHSS limb ataxia item?
- 1
- 2 (Correct answer)
- 3
- 4
Correct answer: 2
The NIHSS limb ataxia item has a maximum score of 2, reflecting ataxia present in two or more limbs.
NIHSS Limb Ataxia 4
A patient with a right cerebellar stroke scores 1 on limb ataxia (right arm ataxic only).
Two hours later, re-examination shows the right leg is now also ataxic.
What is the updated score?