On T2-weighted MRI a lesion is found exclusively within the central grey matter of cervical spinal cord segments C5–C8, producing lower motor neuron signs in both hands but preserved spinothalamic sensation. Which pathway is MOST selectively affected?

• A Anterior horn cells and crossing spinothalamic fibres at the same levels ✓
• B Lateral corticospinal tract (bilateral)
• C Posterior columns (gracile and cuneate fasciculi)
• D Intermediolateral cell column

Explanation

A central cord lesion at C5–C8 destroys anterior horn cells (causing LMN signs — wasting and weakness — in intrinsic hand muscles) and interrupts the decussating spinothalamic fibres crossing in the anterior white commissure (causing a suspended cape-like loss of pain and temperature). Posterior column proprioception and vibration are typically spared early because their fibres lie peripherally in the cord; this pattern is classic for syringomyelia.

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

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.