A teardrop fracture is called that because the fractured fragment of bone, typically from the anteroinferior corner of a cervical vertebral body, resembles a teardrop.
Essentially, the shape of the bone fragment that breaks off during this type of fracture gives it its descriptive name. The small, triangular piece looks like a drop of water poised to fall. This characteristic shape is readily apparent on radiographic imaging, hence the name "teardrop" fracture.
