Steering Pinion Shaft problems of the 2008 Toyota Prius

On 10-28-15, I was driving at a very low speed in a parking lot. As I attempted to turn left to park, I heard a loud crack sound in the steering wheel. The steering wheel became extremely loose and know longer could control the motion of the wheels. I could move forward and backwards but all steering control failed. Thank god I was in a parking lot! I immediately called Toyota and had the car towed there. They could not pinpoint the cause but said I needed a rack and pinion steering wheel shaft replacement, spiral cable, and steering shaft. Repair cost total is $2298. 77. My car is well maintained and has never been in an accident. I'm up to date on recalls so this was very upsetting to me.