For a biomechanical investigation, researchers sought to determine the relative efficiency of modern single and dual implant designs for fixing an extra-articular proximal tibia fracture model. Synthetic tibias were used to produce an extra-articular proximal tibia fracture model. About 4 different constructions were tried. Lateral locked plate (LLP), intramedullary nail (IMN), combined LLP & IMN (PN), and LLP and medial locked plate were the constructs used. Specimens were axially loaded through the medial plateau to assess construct stiffness and resistance to varus collapse.

In the model, dual implant structures were stiffer than single implant constructs. DP and PN were stiffer than IMN at all loads tested. However, the difference was most noticeable at higher stresses. Isolated LLP did not give enough stability to be tested at greater loads. 

The most resistance to varus collapse is provided by dual plate fixation. However, in the clinical situation, the fracture morphology, desired construct stiffness, and soft-tissue envelope must all be considered when deciding on the best build to utilize.

Reference:journals.lww.com/jaaos/Abstract/2022/07010/Fixation_of_Extra_articular_Proximal_Tibia.10.aspx