The patient is positioned in the supine position on a radiolucent table (Fig. 13.3). A small bump is placed under the hip to place the entire lower extremity in a neutral position, which aids in obtaining orthogonal radiographs and does not compromise the surgical approaches necessary for the technique. If the fracture is already spanned with an external fixator and the pins are ideally placed to aid in indirect fracture reduction, the bar and clamp components are removed and the pins prepped into the field. After prepping, we prefer to isolate the pin sites with small sponges to reduce contamination of the sterile surgical wounds.

Approaches for MIPPO of the distal tibia include the workhorse medial approach and, less commonly, the anterolateral approach. Nearly all metaphyseal fractures can be managed via the medial approach. While large, open medial incisions have previously been associated with high wound complication rates, the small incisions, preserve biology, and careful soft tissue handling used in MIPPO techniques have not led to adverse soft tissue problems in larger series of patients.¹,⁴,⁵

The medial approach involves a 2- to 3-cm incision at the tip of the medial malleolus, taking care to preserve the saphenous vein and nerve with the superficial dissection (Figs. 13.4 and 13.5). Once the dissection reaches the periosteal level, a subcutaneous, extraperiosteal tunnel is developed proximally using an elevator or the plate itself, taking diligent care to stay along the anteromedial face of the tibia and not deviate anteriorly or posteriorly. A small 2- to 3-cm proximal window is often helpful to pass the plate centrally on the medial tibia and ensure its proper proximal position.

We prefer the use of modern, precontoured, locking small fragment plates medially because they can be used as indirect reduction aids themselves and allow for fixed-angle stability when managing short metaphyseal segments. In contrast, nonlocking plates can be used and have been associated with good results in a recent series.¹ If the surgeon is bending plates for the medial distal tibia, the local anatomy must be appreciated or else deformity may be imparted. While the coronal plane flare of the medial distal tibia is evident on an AP radiograph (an approximate 20-cm radius of curvature, Figure 13.6A), there is also torsional contour of the medial face of the distal tibia (Fig. 13.6B) that must be addressed. Mast has recommended bending 25 degrees of torsion into the plate, then using a bending press to apply a mild concavity to the plate. As a general rule, (1) the torsional bend is more important to the final reduction than the concavity and (2) the stiffer the implant, the more precise the bend must be or else deformity may be imparted. If the indirect reduction has already been obtained with other adjuvant measures, the plate is fixed proximally and distally with a combination of locking and nonlocking screws (i.e., hybrid plate constructs). In general, we prefer the use of locking screws in the distal metaphysis and nonlocking screws proximally.

When the fracture pattern is simple and amenable to compression, we recommend obtaining distal fixation first then compressing the fracture with either a lag screw tangential to the fracture, with axial compression using an eccentrically drilled hole through the plate, or with the use of an articulated tensioning device. For comminuted fractures in which the plate will be used as a reduction aid, screw placement strategy is variable and depends on the fracture pattern and displacement vectors being reduced (see next section).

The anterolateral approach is particularly useful for pilon fractures with a simple anterolateral articular fracture lines. The incision is 3 to 4 cm in length and centered between the fibula and tibial crests generally in line with the fourth ray and directly over the tibiotalar joint (Bohler incision, Figure 13.7). Care must be exercised with the superficial dissection to avoid injury to the superficial peroneal nerve, which often crosses in the field. The extensor retinaculum is incised and isolated as a separate layer for closure to avoid tendon bowstringing. The underlying extensor digitorum brevis may be gently mobilized laterally in the distal aspect of the incision, if necessary. Capsulotomy exposes the anterolateral plafond, and exposure medially along the anterior surface is necessary to place screws through the anterior plate holes. Anterolateral plates from most manufacturers involve locking anterior to posterior options. After anatomic reduction of the articular surface, the plate can be slid proximally again in an extraperiosteal, submuscular tunnel along the lateral aspect of the tibia deep to the anterior compartment. Unlike the medial approach, the anterolateral MIPPO approach requires a separate proximal incision to identify and protect the deep neurovascular structures, which are intimately related to the anterolateral tibia at this level. These structures may be compressed under the plate, or injured by percutaneously applied screws if not carefully protected.⁶ Because of the anterolateral leg muscles proximally, anterolateral plates are difficult to use as reduction aids, and are most often placed after other reduction techniques have been used.