A COMPARISON OF MALREDUCTION AFTER PLATE AND INTRAMEDULLARY NAIL FIXATION OF FOREARM FRACTURES

A study was performed to compare the degree of malreduction after intr amedullary nail and plate fixation of the forearm and to determine if the degree of malreduction was clinically significant. Eight matched p airs of forearms, including the wrist and elbow joints, were harvested from cadaver upper extremities. The forearms were put through a full range of motion, and physiological loads were applied to simulate thos e during normal use. Standardized anteroposterior and lateral radiogra phs of each forearm were obtained with the specimen intact, and after an osteotomy and internal fixation of one bone, both bones, and with a gap at the osteotomy sites. In each forearm pair, plating was randoml y performed in one specimen and intramedullary nailing was performed i n the matching contralateral specimen. Forearm architecture was assess ed by quantification of the magnitude and location of maximum radial b ow and radial angulation. In this study, plate fixation was superior t o nail stabilization in restoration of the normal radial architecture. Plating did not change any of the radiographic indices (magnitude and location of maximum radial bow and radial angulation) at any stage of testing. None of the radiographic indices was changed by nailing of o nly one of the forearm bones. The magnitude of maximum radial bow and the radial angulation were changed by nailing both forearm bones after osteotomy and both forearm bones with a gap (p < 0.05). Despite this, both techniques were well within the limits of what is radiographical ly acceptable for reduction. The maximum change in magnitude of maximu m radial bow was 1.6 mm, in location of maximum radial bow was 1.4%, a nd in radial angulation was 1.9 degrees. In this study, an anatomic, u nreamed intramedullary nail for the radius and ulna produced minimal d eformity, well within the established limits for good functional outco me. Intramedullary stabilization has the potential to maintain satisfa ctory reduction of diaphyseal forearm fractures.