The comparative strengths of internal fixation techniques

The strengths of internal fixation techniques have been compared by transecting human cadaver metacarpals, reducing and fixing the fractures, and then applying forces to mechanically bend the bone during simulated flexion. Kirschner wires alone, intraosseous wire loops with and without Kirschner wires, and bone plates were tested. Intraosseous loops were tested in three configurations, each with four different wire gauges. Intraosseous loops were stronger than Kirschner wires. Right-angle loops were the best of the intraosseous configurations. The addition of a Kirschner wire strengthened the best dorsopalmar intraosseous loops but not the best right-angle loops. Dorsal bone plates were comparable with the best intraosseous loop configurations of 26-gauge wire.