YAN Hongª²Wei1, LONG Yong2, WANG Kunª²Zheng1, LIU Kai1, HUANG Xiangª²Hui1, LIU Jun1, ZHANG Kaiª²Fang1, SONG Jinª²Hui1

    1Department of Orthopaedics,Second Affiliated Hospital, Medical College, Xi¬ðan Jiaotong University, Xi¬ðan 710004, China£¬ 2Department of Epidemiology, School of Preventive Medicine, Fourth Military Medical University, Xi¬ðan 710033, China

    ¡¾Abstract¡¿ AIM: To discuss the possibility and virtues of a new intramedullary nail for treating unsteady femoral fractures. METHODS: The properties of antiª²axial compression, antiª²lateral bending and antiª²torsion of the new interlocking intraª²medullary nail were tested and compared with those of imported Orthofix interlocking intramedullary nail and AO dynamic compression plate in treating unsteady femoral fracture. RESULTS: In the cases of unsteady fractures, the imported Orthofix nail preª²sented the best antiª²axial compression performance and the new nail the second, and the AO compression plate was the worst; the difference was very significant (P<0.01). The AO compression plate showed the best in both antiª²lateral bending and antiª²torsion, and the new nail performed the second; the differences were also obvious (P<0.01). CONCLUSION: In unsteady fracture, the new developed nails have superior biomechanical characters with a reliable fixation; dynamic compression plate is not the best choice for internal fixation, especially in unsteady fracture; the shape of the narrow part of medullary cavity has a great influence on antiª²lateral bending steady. ......