A humeral fracture fixation system is provided and includes a nail-plate fixation device having a plate-like head portion, an intramedullary nail portion, and a bent neck portion therebetween which creates an angle between the plate and nail portions. The upper surface of the nail portion is substantially straight for contact with the endosteum and the nail portion includes threaded holes for machine screws. The head portion includes locking holes for receiving fixed-angle bone support elements, and K-wire alignment holes. The front of the head portion includes suture holes while presenting a smooth profile. A specific implantation jig and screw guide cannula are also provided.