A longitudinally curved adjustable bone plate comprising a first plate having an end defined by at least two spaced prongs, and an end having means to fasten the plate to a body structure, e.g., the bone; and a second plate having an end defined by at least two straight bores for receiving the prongs, and an end having means to fasten the plate to a body structure, e.g., a bone; and a locking assembly for locking the prongs in the bores and fixing the overall length of the plate.