Posterior cord syndrome below level of injury results in bilateral loss of which modalities?

• A. Light touch and proprioception (DCML)
• B. Motor function
• C. Pain and temperature
• D. Vibration sense only

Answer: (A)

The main idea is that the posterior (dorsal) column–medial lemniscus pathway carries discriminative touch and proprioception (as well as vibration). When the dorsal columns are damaged at a spinal level, these signals are lost below the injury on both sides. That’s why bilateral loss of light touch (discriminative touch) and proprioception occurs. Motor function and pain/temperature travel in other tracts—the corticospinal and spinothalamic systems, respectively—so they are spared in posterior cord syndrome. Vibration is also a DCML modality, but the key point is that the loss centers on DCML functions, matching the described deficit of light touch and proprioception.