I have not seen the movie JFK but I remember watching a part of it where Kevin Costner was explaining the path of the bullet that hit Kennedy. Just like there is no satisfactory answer to who shot Kennedy, there is no satisfactory answer to how Mira broke her leg. Neither Mira, nor her sister who was with her could explain what exactly happened. The fall was not very nasty, just a few inches, neither can they figure out how Mira broke her right leg, and that too at two places, while she fell on her left.