The Huckstep interlocking compression nail was developed in 1967 for complex femur fractures; since 1979, it has also been used for nonunited, difficult, and pathologic fractures of the humerus, ulna, and tibia and also for arthrodesis of the pantalar joints, knee, and elbow. The author has inserted the smaller, solid, square-section 10.5-mm nail with 4.5-mm screws or the 7.5- or 8.5-mm nail with 35-mm screws in 20 humeri, seven tibiae and one ulna for fractures that had been nonunited for up to six years, often remaining so after other implants had failed. All fractures except one were united with minimal complications. This method has proved particularly successful for fractures of the humerus, ulna, and tibia. Nine arthrodeses of the knee, six pantalar arthrodeses, and one arthrodesis of the elbow—all difficult cases often associated with infection—were also performed. Fourteen of 16 of these were successful without any complications.