Seeing a physio will surely be a great ideal. I do not have the luxury of seeing your x-ray,this could have helped in making informed judgement on while u had extention lag. You did not report that your distal femoral fracture communicated into the joint space.Besides malunion of the said fracture could also be responsible for your extention lag.So many factors could be responsible.I am sure,u would surely find solace in the hand of a competent physio.
I am looking forward to seeing u out of this soon.yelufem.