Which mechanism best describes axial loading injuries to the spine?

• A. Axial loading
• B. Hyperextension
• C. Subluxation
• D. Distraction

Answer: (A)

Axial loading is a vertical compressive force transmitted along the length of the spine, such as when a person lands on the feet or buttocks or a heavy object bears down along the spine. This vertical load pushes vertebral bodies together, often causing compression injuries and sometimes burst fractures at the thoracolumbar junction. It’s the mechanism that directly describes injuries from a force moving along the spine’s axis. Other mechanisms involve different directions of force (bending, dislocation, or pulling apart), which produce different patterns of injury that aren’t best described by axial loading.