What best describes a Schmorl's node?

• A. A fracture of the vertebrae
• B. A protrusion of the nucleus pulposus through the vertebral end plate
• C. A rupture of ligaments around the spine
• D. A spinal disc degeneration

Answer: (B)

A Schmorl's node is characterized by a protrusion of the nucleus pulposus through the vertebral end plate into the vertebral body. This phenomenon occurs when the jelly-like center of an intervertebral disc pushes upward or downward into the adjacent vertebrae, often as a result of degenerative changes or excessive loading of the spine. Schmorl's nodes are typically found incidentally during imaging studies and can be associated with conditions such as disc herniation or degenerative disc disease.

In comparison, the other options refer to different spinal pathologies. The first option pertains to a vertebral fracture, which involves a break in the integrity of the vertebrate bone and does not specifically describe the mechanism involved in a Schmorl's node. The third option, a rupture of ligaments around the spine, describes soft tissue injuries that can accompany various spinal conditions but are not indicative of a Schmorl's node. Finally, spinal disc degeneration addresses the general wear and tear of intervertebral discs over time and does not specifically encapsulate the unique phenomenon of a Schmorl's node. Thus, describing a Schmorl's node accurately as a protrusion of the nucleus pulposus through the vertebral end plate is fundamental in differentiating it from