Owners/service Manual problems of the 2006 Toyota Avalon

While sitting at a stop light, I heard a tremendous, sharp noise coming from the rear of the car. I thought the car had been hit with a rock or hard ball, but nobody in the cars around me seemed to have any concern or acknowledgement of something having hit my car. Upon pulling over and opening the trunk, I realized the trunk had no counterbalance and would not pop open or stay opened once manually lifted, creating a dangerous situation in which the trunk, without being held open, will slam shut with tremendous force. I have taken the car to two separate shops and they explained that the torsion bar ripped through/out of the brackets holding it onto the trunk structure. The repairs will require welding inside the trunk--a very expensive and potentially dangerous repair. The brackets will need to be removed and replaced. Both shops expressed that this appears to have been a design flaw and that it really should not have happened if the trunk had been properly designed and manufactured with sufficiently strong parts.