In syringomyelia, which region is typically affected?

• A. Lower extremities
• B. Upper extremities
• C. Cranial nerves
• D. Trunk

Answer: (B)

Syringomyelia most often begins in the cervical spinal cord, and the key feature is disruption of the crossing fibers that carry pain and temperature from the arms. This leads to a bilateral loss of pain and temperature in the shoulder and arm region—the cape-like distribution over the shoulders and arms. Because the dorsal columns (vibration and proprioception) are typically spared early, fine touch and position sense remain intact at first. As the syrinx expands, weakness and atrophy can develop in hand muscles. Cranial nerves aren’t usually affected unless the syrinx extends upward into the brainstem, and involvement of the trunk or lower extremities would occur only if the lesion grows beyond the cervical level.