Casey was injured on February 4th, 2017, while snowboarding on Mount Shasta. After a night of rain the snow was stickier than usual, but he decided to continue with his regular jump runs. On his second jump, he attempted a simple 180. However, just before takeoff, he hit a small, sticky patch of snow at the top of the jump. Instead of rotating horizontally, he fell forward, somersaulting, and landed on his back, directly on the hip of the landing zone. Immediately, amid the pain in his back, he realized he couldn’t feel his legs.