What Is Next Procedure After The Surgery Of Implant In Knee To Straighten?

i was in a car wreck and slammed my left knee on the dash or stearing column, my wreck happened in january, we didnt find out i had a tear till feburary, and had surgery in march, where my doc had to put an implant in, im currently in p.t 2x a week, my bending is getting better but i cant straighten my leg out all the way, after 3 wks of p.t its still not getting better and not showing any improvement on straightening. if they do surgery again what are they going to do?