<prompt> Whiplash injury is caused due to -A fall from a heightAcute hyperextension of the spineA blow on top to headAcute hyperflexion of the spine  <response>: Whiplash injury results from acute hyperextension of the cervical spine in the region of C4-C6 vertebrae.Note: Both hyperflexion and hyperextension i.e. flexion followed by hyperextension are involved in the mechanism of whiplash injury. But it is hyperextension which causes damage to the spinal cord. 