What type of force, when applied to the spine, results in shearing injuries?

Shearing injuries to the spine occur when different parts of the spinal column are displaced in opposite directions, leading to stress on the intervertebral discs and adjacent structures. A horizontal force applied to the spine can create a scenario where the upper body moves laterally while the lower body remains relatively fixed, resulting in shear stresses. This dynamic creates forces that can cause the vertebrae to slide over one another, which is characteristic of shearing injuries.

Contrastingly, vertical forces typically compress the spinal structures, which does not lead to shearing. Rotational forces can also influence the spine but typically result in torsional injuries rather than pure shear. Axial forces focus along the length of the spinal column, primarily affecting compression rather than providing the lateral stress that induces shearing. Thus, the horizontal force is the mechanism that effectively leads to shearing injuries in the spine.