An employee was operating a lawn tractor up a paved roadway when the tractor went into neutral and started rolling backward down the hill. The employee turned the wheel and the tractor flipped onto its side. The vehicle was equipped with a rollover protection system and the employee was wearing his seatbelt. When the tractor flipped on its side, the employee's fingertips were pinched between the ground and the tractor, resulting in a left middle fingertip amputation.