Effect of Physical Therapy on Vestibular Function in Body Lateropulsion Following Wallenberg Syndrome: A Case Report Using the Modified Clinical Test of Sensory Interaction and Balance

Balance training, consisting of postural control exercises, has been shown to enhance vestibular-related postural function in individuals with body lateropulsion (BL), a condition characterized by abnormal lateral displacement of body mass and increased lateral sway when estimating the center of pressure at rest. We report a single case showing quantitative and longitudinal changes in estimated vestibular-related postural function using the modified Clinical Test of Sensory Interaction and Balance (mCTSIB), which evaluates postural control by isolating vestibular input while controlling for visual and somatosensory influences. A 52-year-old male presented with right-sided BL and was diagnosed with lateral medullary infarction (Wallenberg syndrome). Vestibular-related postural function was assessed repeatedly using the mCTSIB during a structured physical therapy program that included postural control and balance training. Initially, the patient exhibited right-sided BL and ataxia, requiring assistance with ambulation due to a deviation in subjective visual vertical (SVV). Over time, SVV normalized, corresponding with improvements in the estimated vestibular function area derived from the maximum entropy method within the 0.2-2.0 Hz range on the mCTSIB. The patient ultimately regained independence in activities of daily living, and no adverse events occurred during therapy. This case suggests that postural control training may be associated with the recovery of vestibular-related postural function in individuals with BL. Quantitative assessment using the mCTSIB may provide a valuable framework for monitoring vestibular rehabilitation outcomes. However, as this observation is based on a single case, the findings should be interpreted cautiously and warrant further validation through larger studies.