Tibial fractures of sufficient severity to warrent internal fixation are a significant injury. Even an undisplaced stable tibial fracture not requiring internal fixation may require 3- 6 months for full weight bearing to take place.
To reliably manage an aircraft with a sudden engine failure after take off you need incontrovertable power and control from the relevent rudder...
I would suggest that you should think in terms of a minimum of 6 months for return to full flying duties..
It is impossible to give really accurate advice with out seeing your X-rays... there is a very wide spectrum of degrees of severity of this injury.. Your Orthopaedic Surgeon is by far the best person to advise... in consultation with the CAA med Docs.. if nec..
Good luck.. and work hard at the physio and you will be back up there soon....
Cyan