Cerebellar signs
Formal Definition
Clinical findings indicating cerebellar dysfunction, including ataxia, dysmetria (finger-nose-finger or heel-shin testing), dysdiadochokinesia (impaired rapid alternating movements), nystagmus, intentional tremor, wide-based gait, and dysarthria; localized to ipsilateral cerebellar hemisphere or vermis.
How It's Used on the Ward
"Cerebellar signs" or "ataxic" or "dysmetric" — key findings when evaluating dizziness, falls, or posterior circulation strokes.
Example
""Older man with sudden onset vertigo and vomiting: can't walk without falling to the right, finger-nose-finger shows right-sided dysmetria, nystagmus on rightward gaze. This isn't vestibular neuritis — this is a posterior circulation stroke. Getting CT/MRI emergently.""
Clinical Context
The HINTS exam (Head Impulse, Nystagmus, Test of Skew) distinguishes central from peripheral vertigo at the bedside — a normal head impulse test in the setting of vertigo strongly suggests central (cerebellar/brainstem) pathology. Cerebellar strokes may not appear on CT in the first 24 hours — MRI with DWI is the definitive study. The posterior fossa "silent zone": large cerebellar infarcts can cause herniation with little warning — any cerebellar stroke needs close monitoring.