We evaluated both the outcome of using a locking plate as a definitive
external fixator for treating open
tibial fractures and, using finite
element analysis, the biomechanical performance of external and internal metaphyseal locked plates in treating proximal
tibial fractures. Eight open tibial patients were treated using a metaphyseal locked plate as a low-profile definitive
external fixator. Then, finite
element models of internal (IPF) as well as two different external plate fixations (EPFs) for proximal
tibial fractures were reconstructed. The offset distances from the bone surface to the EPFs were 6 cm and 10 cm. Both axial stiffness and angular stiffness were calculated to evaluate the biomechanical performance of these three models. The mean follow-up period was 31 months (range, 18-43 months). All the fractures united and the mean bone healing time was 37.5 weeks (range, 20-52 weeks). All patients had excellent or good functional results and were walking freely at the final follow-up. The finite
element finding revealed that axial stiffness and angular stiffness decreased as the offset distance from the bone surface increased. Compared to the IPF models, in the two EPF models, axial stiffness decreased by 84-94%, whereas the angular stiffness decreased by 12-21%. The locking plate used as a definitive
external fixator provided a high rate of union. While the locking plate is not totally rigid, it is clinically stable and may be advisable for stiffness reduction of plating constructs, thus promoting fracture healing by callus formation. Our patients experienced a comfortable
clinical course, excellent knee and ankle joint motion, satisfactory functional results and an acceptable complication rate.