I HAD JUST FINISHED VACUUMING THE INSIDE OF MY 2011 FORD FLEX. THE REAR AUTOMATIC LIFTGATE WAS UP AND I WAS LEANING INTO THE BACK OF THE FLEX REINSTALLING MY CARGO NET WHEN THE HYDRAULICS FAILED AND THE LIFTGATE CAME SLAMMING DOWN ON MY BACK. I SUSTAINED BRUISING AND MUSCLE INJURY. IF IT WAS MY ARM OR LEG IT MIGHT HAVE RESULTED IN AN AMPUTATION. IF IT WAS MY HEAD / NECK IT COULD HAVE RESULTED IN A FATALITY. IF IT WAS MY CHILD HE COULD HAVE BEEN PARALYZED. WHY ARE THERE NO SAFETY FEATURES THAT PREVENTS THE LIFTGATE FROM SLAMMING SHUT IF THE HYDRAULICS FAIL?