L.S. unless you are sure he pushed you down the stairs intentionaly, you should not issue anything. There are many law options to fire up here: issue law violation to procurator, having procurator initiate court (if you initiate it yourself- a lot of expense is risked). This way you would make subject false testify at court at least. Considering in options such as truth detector and such, the subject would get revealed.
But, if there is a criminal who intentionaly pushed you falling down the stairs, situation is a bit different. This would be a serious hurt atempt, wheather a murder atempt or serious health invalidation attempt. If you know what you are in, handle it your way, at your assumptions, for there is a lot of information and facts, considering what you have faced actualy.
Myself, if I was sure he wanted me to break down the stairs, I would get myself tear gas and knife. Making the pathologic person disapear to his responsibility, or , get myself out. Cannot say what has happened exactly though, from what has been (strangely) described.