He for sure is really banged up and there could be secondary issues that nobody even is aware of yet. One possible mitigation is that the engine may have been pushed in against his legs only, crushing them, but leaving his upper body and that oh so fragile back intact. Let’s hope...If it's just broken bones, he'll likely be fine; though maybe never at an elite level. My worry is that an impact significant enough to shatter your bones will surely have some effect on your joints. Ligament and tendon damage would potentially reduce his range of motion. Not much coming back from that.