If a patient cannot stand with feet together regardless of eye status, this suggests a lesion in which region?

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

Answer: (B)

Coordinate control and balance depend on the cerebellum to fine-tune movements and maintain truncal posture. When a cerebellar lesion is present, you get ataxia that affects posture and gait, producing a wide, unsteady stance that is not corrected by simply having the patient look around. The key clue here is that the patient cannot stand with feet together regardless of eye status, which points to a problem with the brain’s coordination center rather than a sensory deficit.

In sensory (posterior column) ataxia, the loss of proprioception is best compensated by vision; the classic sign is a positive Romberg becoming evident mainly with eyes closed. Basal ganglia disorders cause movement abnormalities like bradykinesia, rigidity, and tremor rather than an ataxic stance. Peripheral nerve issues cause proprioceptive loss as well, but again balance worsens when vision is removed. Thus, the description most consistent with a cerebellar lesion.