“Roof crush” refers to the structural collapse of a vehicle’s roof during a rollover, which reduces the survivable space inside the cabin and can drive the roofline down directly onto an occupant’s head and neck. When that downward force is transmitted through the top of the skull into the cervical spine, it can compress and shatter a vertebra from multiple directions at once — an injury known as a burst fracture, which is especially dangerous because bone fragments can be driven directly into the spinal canal, damaging or severing the spinal cord itself.

The location and severity of a burst fracture largely determines the outcome. A burst fracture high in the cervical spine, which is disproportionately common in roof crush injuries because the roof intrudes downward onto the neck first, frequently results in quadriplegia — paralysis affecting all four limbs. A burst fracture lower in the spine, in the thoracic or lumbar region, more often results in paraplegia, affecting the legs and lower body while preserving arm and hand function. Because roof crush injuries tend to involve extreme, concentrated force delivered in a fraction of a second, they’re also more likely to result in a complete spinal cord injury — total loss of function below the injury site — than injuries from lower-force accident mechanisms.