Patent ID: 8758415

Claim:
A system for angularly stable fixation of a bone plate to a bone having a non-cylindrical opening therein for fracture fixation, the system comprising: a sonotrode having a threaded tip; a plate adapted to mount on the bone, the plate having a first non-cylindrical opening, the plate having a first non-cylindrical opening extending along a first axis, the plate first non-cylindrical opening capable of being substantially aligned with the non-cylindrical opening in the bone; and a pin comprising a portion having a non-circular cross-section perpendicular to a pin longitudinal axis the pin capable of being inserted through the plate first opening into the bone non-cylindrical opening and capable of receiving energy to melt at least a portion of the pin, wherein the melted material of the pin is capable of solidifying to weld the pin to the bone and the plate to form an angularly stable implant that does not rotate with respect to the bone, wherein the pin has a bore along its longitudinal axis, wherein the bore is threaded and adapted to receive the threaded tip of the sonotrode.