If a patient can stand with feet together with eyes open but cannot with eyes closed, damage is to which structure and gait?

• A. Posterior column, sensory ataxia
• B. Cerebellum, cerebellar ataxia
• C. Basal ganglia, parkinsonian gait
• D. Peripheral nerves, steppage gait

Answer: (A)

The key idea is how balance relies on proprioceptive input from the body and how vision helps when proprioception is lost. If a patient can stand with feet together with eyes open but cannot when eyes are closed, this is a positive Romberg sign pointing to loss of position sense coming from the dorsal (posterior) columns. These columns carry proprioception and vibration information to the brain, and when they’re damaged, there’s sensory ataxia: a broad, unsteady gait and increased swaying that worsens without visual input. Hence, the structure involved is the posterior column, producing sensory ataxia. In contrast, cerebellar ataxia typically worsens even with eyes open and shows dysmetria and tremor, basal ganglia–driven gait involves rigidity and bradykinesia, and peripheral neuropathy causes a different pattern of weakness and foot position issues rather than a Romberg-positive balance problem.