Serious injuries to the spine are usually caused by axial forces caused by a head impact or by bending and squeezing forces caused by an impact on shoulders, hips or other parts of the body. In the standards for motorcycle clothing set by Cambridge, Roderick Woods states that the effects on spinal injuries have the greatest impact on shoulders and hips. In rare cases where a motorcyclist is hit directly in the back, the damage caused by the protector cannot be reduced. The idea of the back protector itself was not supported by Woods. Although they are a standard, they cannot protect against axial forces, but are required to protect the shoulders. This is a proof that wearing a certified back protector can significantly reduce the damage caused by the impact.