Anterolateral Versus Medial Plating of Distal Extra-articular Tibia Fractures: A Biomechanical Model

Both medial and anterolateral plate applications have been described for the treatment of distal tibia fractures, each with distinct advantages and disadvantages. The objective of this study was to compare the biomechanical properties of medial and anterolateral plating constructs used to stabilize simulated varus and valgus fracture patterns of the distal tibia. In 16 synthetic tibia models, a 45° oblique cut was made to model an Orthopedic Trauma Association type 43-A1.2 distal tibia fracture in either a varus or valgus injury pattern. Each fracture was then reduced and plated with a precontoured medial or anterolateral distal tibia plate. The specimens were biomechanically tested in axial and torsional loading, cyclic axial loading, and load to failure. For the varus fracture pattern, medial plating showed less fracture site displacement and rotation and was stiffer in both axial and torsional loading (P<.05). For the valgus fracture pattern, there was no statistically significant difference between medial and anterolateral plating. There were no significant differences between the 2 constructs for either fracture pattern with respect to ultimate load, displacement, or energy absorption in load to failure testing. When used to stabilize varus fracture patterns, medial plates showed superior biomechanical performance compared with anterolateral plates. In this application, the medial plates functioned in anti-glide mode. For valgus fracture patterns, no biomechanical differences between anterolateral and medial plating were observed. In clinical practice, surgeons should take this biomechanical evidence into account when devising a treatment strategy for fixation of distal tibia fractures.