TECHNICAL TRICK Fibular Shaft Allograft Support of Posterior Joint Depression in Tibial Plateau Fractures Adam A. Sassoon, MD, Michael E. Torchia, MD, William W. Cross, MD, Joseph R. Cass, MD, and S. Andrew Sems, MD Summary: Posterior depression of the lateral articular surface of the tibial plateau can be difficult to elevate and support with morselized bone graft and internal fixation. Progressive collapse after open reduction and internal fixation has been described and can lead to failure in treatment. A standard anterolateral approach to the tibia may not allow direct reduction and stabilization of posterolateral joint depression given the anatomic barriers of the fibular collateral ligament and the proximal tibiofibular articulation. Posterolateral approaches to the tibial plateau have been described and may allow direct reduction of the articular depression. These approaches, however, require dissection close to the common peroneal nerve, and some approaches also require a proximal fibular osteotomy. The use of an intraosseous fibular shaft allograft as an adjunct to open reduction and internal fixation in select cases of depressed posterolateral tibial plateau fractures allows both reduction of the joint and stabilization of the articular segment through a single approach familiar to many orthopaedic surgeons. Key Words: tibial plateau fracture, plateau, reduction, bone graft, technique (J Orthop Trauma 2014;28:e169–e175) INTRODUCTION Articular depression of the posterolateral tibial plateau has been recognized in a subset of patients with tibial plateau fractures. 1–8 Surgical strategies have generally involved ante- rolateral approaches with the elevation of this articular seg- ment followed by filling of the defect with bone grafting or bone graft substitute, 8 with subsequent lateral plate and screw fixation. Through this approach, implants can be used to cre- ate “rafting” constructs with multiple screws or smooth wires to provide subchondral support of this segment. However, posterior positioning of anterolateral plates is limited by the location of the fibular head and lateral (fibular) collateral ligament. Consequently, the posterior section of the articular surface on the lateral tibial plateau may not be supported by implants. Postoperative displacement of the elevated postero- lateral articular segments may occur despite addressing the joint impaction with current methods. This article presents a novel technique, which aids in both the reduction and sta- bilization of posterolateral articular impaction. RATIONALE FOR THIS TECHNIQUE Current plate technology may not adequately position proximal subchondral screws (raft screws) to support pos- terolateral joint surface impaction injuries. To evaluate and characterize this phenomenon, a bicondylar tibial plateau model was designed based on a previously described model that has been validated against a cadaveric model. 9 This model used a solid foam tibial model (Sawbones model 1116; Pacific Research Laboratories, Seattle, WA) reinforced with a 12.7-mm-diameter carbon fiber rod secured in the intramedullary canal of the diaphysis of the model, ending 80 mm distal to the plateau (Tuflon 10 G/40; Tuflon Ltd, Birmingham, United Kingdom). All fracture models were created on a band saw using an alignment jig to ensure accu- rate reproductions of all cuts. Six different plates from 5 leading manufacturers were applied to the anterolateral aspect of the tibia. Each company supplied 5 plates and these were fit to 5 models giving us 30 specimens. The plates that were tested included the Less Invasive Stabilization System (Synthes Inc, West Chester, PA), 4.5-mm LCP Proximal Tibia Plate (Synthes Inc, West Chester, PA), 5.5-mm Periarticular Locking Proximal Tibial Plate (Zimmer Inc, Warsaw, IN), Polyax Tibial Plate (Depuy, Warsaw, IN), Peri-Loc (Smith and Nephew, Memphis, TN), and the AxSOS Plate (Stryker Orthopaedics, Mahwah, NJ). The tested plates thereby spanned a range of proximal locking screw diameters from 3.5 to 5.5 mm. No sources of outside funding were used for completion of this study. The plates were positioned on the anterolateral surface of the tibial model. This tibial model has an indentation in the tibia representing the proximal tibiofibular joint, and the plate was positioned so that the posterior edge of the proximal flare of the plate was at the anterior margin of this recess. The plate contouring was used to determine the location of the plate in the proximal–distal direction, by manually applying the plate to the anterolateral tibia, and then sliding it proximally until the tibial flare prevented any more proximal positioning with- out lifting the plate away from the tibial diaphysis. The loca- tion of the posterior-most rafting screw was determined, and the distance from that screw to the most posterior edge of the lateral tibial plateau was measured using a digital caliper system. The area of unsupported posterolateral articular Accepted for publication September 24, 2013. From the Department of Orthopaedic Surgery, Mayo Clinic, Rochester, MN. W. W. Cross received teaching honorarium from AONA/Synthes and consulting fee from Innovative Medical Device Solutions. S. A. Sems received Royalties from Biomet. The remaining authors report no conflict of interest. Reprints: S. Andrew Sems, MD, Mayo Clinic, 200 First St, SW, Rochester, MN 55905 (e-mail: sems.stephen@mayo.edu). Copyright © 2013 by Lippincott Williams & Wilkins J Orthop Trauma  Volume 28, Number 7, July 2014 www.jorthotrauma.com | e169