A patient has a Brown-Séquard syndrome at C6 on the right. Which combination of findings is internally consistent with a RIGHT C6 hemicord lesion?

• A Right arm weakness, right leg spasticity; loss of pain/temperature on the right arm and leg; loss of proprioception on the left
• B Right arm and leg weakness and spasticity; loss of proprioception on the right; loss of pain/temperature on the left below C6 ✓
• C Left arm and leg weakness; loss of pain/temperature on the right below C6; intact proprioception bilaterally
• D Right arm flaccid weakness at C6 level; bilateral spasticity below; loss of all sensation below C6 bilaterally

Explanation

Brown-Séquard syndrome from a right C6 lesion produces: (1) ipsilateral (right) UMN weakness below the lesion (right leg spasticity) plus ipsilateral LMN weakness at the level (right C6 myotome — segmental flaccidity at C6 level); (2) ipsilateral (right) loss of proprioception and vibration (dorsal columns do not decussate in the cord); (3) contralateral (left) loss of pain and temperature below C6 (spinothalamic fibres decussate 1-2 levels above entry). Option A incorrectly places sensory loss ipsilaterally. Option C incorrectly gives contralateral weakness. Option D describes a complete cord lesion, not hemi-cord.

Reference: BD Chaurasia's Human Anatomy, 8th ed.

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Written and medically reviewed by the StethoPrep medical team.