Evaluating Postural Control Functions With a Focus on Vestibular Sensation in Thalamic Astasia: A Case Report

Thalamic astasia (TA) is a condition characterized by difficulty maintaining an upright posture due to a unilateral lesion in the thalamus. Motor paralysis, sensory disturbances, and ataxia are typically absent or mild. While vestibular dysfunction has been implicated in the onset of TA, a comprehensive evaluation strategy that considers vestibular function has yet to be established. In this report, we present a case of TA following a left thalamic infarction where the patient exhibited no abnormalities in their subjective vertical visual (SVV) function, which is often used as an indicator of vestibular function, and we discuss the potential utility of the modified Clinical Test of Sensory Interaction and Balance (mCTSIB) in patients with TA.