SUBARU OUTBACK (2012), WHEN STOPPED FOR 1-2 MINUTES, WITH THE ENGINE AND IGNITION OFF, AND THE GEAR SHIFT IN PARK, ON A SLIGHT INCLINE (TO CHECK A POTENTIAL SAFETY HAZARD) SUDDENLY ROLLED BACKWARDS AS I WAS LEANING IN TO RETRIEVE MY BAG. I WAS DRAGGED ACROSS THE NORMALLY BUSY ROAD, BARELY ABLE TO HANG ON (BY BOTH HANDS GRABBING ANYTHING I COULD INSIDE THE CAR). MY LEGS SCRAPED ON THE GROUND VIOLENTLY BURNING THOUGH MY SNEAKER THEN ANKLE FLESH AND GRAZED THE BONE BADLY. MY LEGS ON THE ROAD TURNED THE 1.5 TON VEHICLE A FEW DEGREES AS IT CAREENED UNDER RAPID ACCELERATION REACHING AN ESTIMATED 8-10 MPH BUMPING OVER 2 KERBS PULLED ME EVEN FURTHER OUT OF THE CAR, BUT STILL HANGING ON. LUCKILY THE OPEN DRIVER'S DOOR ENGAGED WITH A HEDGE WHICH RIPPED THE DOOR ALMOST OFF THE CAR AND TURNED THE CAR ANOTHER 35 DEGREES OR SO, AVOIDING A VIOLENT CRASH INTO THE NEIGHBOR'S HOUSE. INSTEAD THE CAR GRAZED A WOODEN POST (FURTHER SLOWING IT) THEN HIT A SECOND POST WHICH BROUGHT THE CAR TO A HARD STOP. THIS PUSHED ME OUT OF THE CAR ONTO A PATCH OF GRASS, BACK TO THE CAR. AN ENGINEERING ASSESSMENT LATER REVEALED THE SHIFT-INTERLOCK HAD FAILED (INVOLVING A COUPLE OF PARTS) SO THAT THE GEAR MAY BE SHIFTED (OR SHIFT ITSELF) WHEN THE ENGINE AND IGNITION ARE OFF WITH THE KEYS STILL IN. MY INJURIES INCLUDE ANKLE (ON A LEG WITH A HIP REPLACEMENT), PTSD (DIAGNOSED AS CAUSED 100% BY THE CRASH) AND EXACERBATION OF MULTIPLE-SCLEROSIS CAUSING DEBILITATING BOUTS OF TRIGEMINAL NEURALGIA AND WITH ADDITIONAL BRA