A cortical shaft bone fixation apparatus includes a housing having a leading portion and a trailing portion, the leading portion configured to fit within a diameter of an affected cortical shaft bone, the leading portion having first and second sections. The apparatus further includes an expansion mechanism adapted to transition the first and second sections from a first position to a second position, the first and second sections providing an outward force against the inside surface of the cortical shaft bone when the first and second sections transition from the first position to the second position, the trailing portion of the housing abutting a leading end of the affected cortical shaft bone. The trailing portion of the housing includes a pair of angled tapers extending inwardly toward each other to a minimum separation distance at an extreme end of the housing.