Abstract: Both a bone fixation device and a method for retrofitting this device in a conventional hollow, intramedullary nail are disclosed herein. The bone fixation device of the invention generally comprises at least one blade member having a top portion registrable with a blade slot provided in the body of the nail, and a bottom surface including a rail slot, as well as at least one wedge member having an inclined top surface for transmitting a blade extending force to the bottom surface of the blade member, as well as a rail which is slidably engageable with the blade member slot. The blade slot and wedge rail interlock to provide a positive retracting force on the blade when it is desired to remove the nail from a bone. Additionally, the wedge member includes a key which interlocks with the longitudinal slot which extends along the longitudinal axis of a conventional Kuntscher intramedullary nail in order to facilitate angular alignment of the blade member with the blade receiving slot in the nail.