The mantrip derailed at 12 break and hit the rib inby the corner and then spun around and hit corner with left side of mantrip, thus spinning until rear of mantrip was facing outby. Their were 7 employees in mantrip, 5 were transported to hospital with 2 being held overnight for observation. 1 suffered a broken shin & dislocated ankle, the other a laceration to the head.