In Brown-Sequard syndrome, which pattern of sensory loss is expected below the level of the lesion?

In Brown-Sequard syndrome, which pattern of sensory loss is expected below the level of the lesion?

• A. Ipsilateral motor weakness with loss of vibration/proprioception; contralateral loss of pain and temperature
• B. Bilateral weakness
• C. Contralateral motor weakness
• D. Ipsilateral loss of pain only

Answer: (A)

Brown-Sequard syndrome arises from a hemisection of the spinal cord, so the pathways that run on the two sides are affected differently below the lesion. The same-side corticospinal tract is disrupted, producing motor weakness on the side of the lesion below that level. The same-side dorsal columns are also damaged, leading to loss of vibration and proprioception on the same side below the lesion. Meanwhile, the fibers carrying pain and temperature in the spinothalamic tract have already crossed to the opposite side near entry, so sensation of pain and temperature is lost on the opposite side below the lesion. In sum, below the lesion you get ipsilateral motor weakness with loss of vibration and proprioception, and contralateral loss of pain and temperature.

Brown-Sequard syndrome arises from a hemisection of the spinal cord, so the pathways that run on the two sides are affected differently below the lesion. The same-side corticospinal tract is disrupted, producing motor weakness on the side of the lesion below that level. The same-side dorsal columns are also damaged, leading to loss of vibration and proprioception on the same side below the lesion. Meanwhile, the fibers carrying pain and temperature in the spinothalamic tract have already crossed to the opposite side near entry, so sensation of pain and temperature is lost on the opposite side below the lesion. In sum, below the lesion you get ipsilateral motor weakness with loss of vibration and proprioception, and contralateral loss of pain and temperature.