Brown-Sequard syndrome results in which pattern?

Brown-Sequard syndrome results in which pattern?

• A. Loss of motor weakness and proprioception on the same side as lesion, with loss of pain and temperature on the opposite side
• B. Bilateral motor weakness
• C. Loss of pain and temperature on both sides
• D. Loss of proprioception only on the opposite side

Answer: (A)

Brown-Sequard syndrome comes from a hemicord injury, so one side of the spinal cord is damaged. The corticospinal tract and the dorsal columns, which carry voluntary movement and proprioception (and fine touch/vibration), travel on the same side as the injury. Damaging them on one side leads to weakness and loss of proprioception on that same side below the lesion. The pain and temperature pathway (spinothalamic tract) crosses to the opposite side within a couple of segments after entering the spinal cord, so those sensations are lost on the opposite side below the lesion. Taken together, you get ipsilateral motor weakness and loss of proprioception, with contralateral loss of pain and temperature. This pattern distinguishes Brown-Sequard from conditions that produce bilateral deficits or different unilateral patterns.

Brown-Sequard syndrome comes from a hemicord injury, so one side of the spinal cord is damaged. The corticospinal tract and the dorsal columns, which carry voluntary movement and proprioception (and fine touch/vibration), travel on the same side as the injury. Damaging them on one side leads to weakness and loss of proprioception on that same side below the lesion. The pain and temperature pathway (spinothalamic tract) crosses to the opposite side within a couple of segments after entering the spinal cord, so those sensations are lost on the opposite side below the lesion. Taken together, you get ipsilateral motor weakness and loss of proprioception, with contralateral loss of pain and temperature. This pattern distinguishes Brown-Sequard from conditions that produce bilateral deficits or different unilateral patterns.