Posteromedial Approach to the Tibial Plateau

What it exposes. The posteromedial approach gives direct access to the posteromedial tibial plateau and posterior coronal split fragments of the medial column — fragments that occur in approximately 10 to 15 percent of tibial plateau fractures and are frequently missed on plain radiographs. It is the workhorse exposure for buttress plating of posteromedial split and split-depression fragments. Why posterior (and not anteromedial). A standard anteromedial approach cannot place a true posterior buttress plate. Posteromedial fragments displace posteriorly under axial load, so a buttress plate on the posterior surface is biomechanically required to resist re-displacement. The posteromedial approach allows anatomic reduction under direct vision and correct buttress-plate placement. Position. The patient is placed prone on a radiolucent table with the knee flexed 20 to 30 degrees over a bump — gravity retracts the gastrocnemius and gives direct posterior access. The leg is prepared and draped free, and a tourniquet is applied but usually not inflated unless bleeding obscures vision. The floppy lateral position (affected side up, knee flexed) is an alternative that reaches both posteromedial and posterolateral columns without repositioning, useful when combined approaches are planned. Landmarks. Palpate and mark the posteromedial border of the proximal tibia, the medial head of gastrocnemius, the pes anserinus insertion on the medial tibia, the joint line (with the knee flexed), and the fibular head (to orient the popliteal fossa). Approach variants.

Work down through the layers along the posteromedial border, protecting the saphenous nerve and vein superficially, then develop the pes-anserinus to medial-gastrocnemius interval to reach the posterior cortex while guarding the popliteal bundle.

View larger

Structures at risk, by layer

The saphenous nerve is the structure most often injured if it is not actively identified; injury causes medial calf sensory loss and possible neuroma pain. The popliteal artery is the most serious — injury can result in limb loss. Tibial nerve injury causes plantarflexion weakness and sensory loss on the sole. Extensile options. Extend proximally along the medial border of the gastrocnemius to expose more of the posterior femoral condyle (protect the saphenous nerve again during this extension). Extend distally along the posteromedial border of the tibia, further elevating the soleus, taking care to avoid the posterior tibial artery and tibial nerve as they course distally. Closure. Close the posterior capsule if it was opened; the soleus origin is not repaired; close the fascia loosely to avoid compartment syndrome; close subcutaneous tissue in layers; skin with interrupted nylon or staples. Place a drain if dissection was extensive.

• Tibial plateau ORIF — open reduction and internal fixation of isolated posteromedial tibial plateau fractures.
• Buttress plating of posteromedial split or split-depression fragments.
• Fixation of posterior coronal plane fractures of the medial plateau.
• Combined approaches for bicondylar fractures, used with the anterolateral approach.
• Revision surgery for posteromedial malunion or nonunion.
• Bone grafting of posteromedial metaphyseal defects.