Why do they do this????? ?

Okay my friend was pushed from a high ledge. And he dislocated his hip and badly broke his pelvis so i called 911 and the ambulance people put him him in a neckbrace and put this strap thing on his stomach and legs and did other stuff to him why did they do that he didnt even have a neck injury?? My friend said he hated it and it was uncomfortable but why would they do that to him?