Vacuum Bell question

I just received my vacuum bell from Pectus Healing after much delay and I can't wait to try it out. I have a question lingered in my mind that need some clarification: the instruction said after the vacuum is released the sternum and ribs will fall back slowly, but would it have the off chance where the sternum and ribs falling (think of it like a house of cards) to its original position and hitting the organs underneath?

Your experiences and clarifications are highly appreciated. Thanks