Motorcyclist's fracture is -

Ads. is 'b' i.e., Transverse fracture across base of skull Motorcyclist's fractureo Because of the inherent instability of two wheeled vehicles, the rider and passanger inevitably fall to the ground in a crash. Injuries can occur to any part of the body, but the limbs and head are particularly susceptible to serious injury.o Impact with the road surface or another vehicle at speed often causes skull fracture, even in the presence of a helmet.o A transverse fracture across the floor of the skulk usually called a "hinge fracture", is sometimes referred to as motorcyclist fracture. At autopsy, the base of the skull may be appriciated to have divided into two halves, each moving independently of each other like a hinge, the so-called motorcyclist fracture.