Fractures that involve the posteromedial tibial plateau are seen with high-energy injuries and require special attention when developing a preoperative plan. These medial-sided fractures often require a separate medial approach and plating strategy because an isolated lateral plate will not adequately stabilize a displaced medial plateau. Here, we describe this approach and tips for reduction and fixation in a case of an isolated posteromedial tibial plateau fracture.
The Lobenhoffer approach was first described in the German literature in 2003 and is used to access the posteromedial and posterior aspects of the tibial plateau. It allows for visualization of the posteromedial tibia and, if needed, can be developed laterally to allow access to the posterior and even posterolateral tibia. There are numerous advantages to this approach. The neurovascular bundle is not exposed and therefore is protected within the posterior soft tissues. Wound healing and coverage of implants is reliable because of the large soft-tissue envelope over the posteromedial proximal tibia. The visualization provided by the Lobenhoffer approach allows for accurate reduction of the extraarticular portion of the fracture followed by placement of a posterior antiglade plate.
The case presented is of a 39-year-old man who was involved in a dirt bike accident. He was found to have a posteromedial tibial plateau fracture (OTA 41-B3.2, Moore type 1) and taken for closed reduction and knee-spanning external fixation. Definitive fixation is delayed until healing of the soft-tissue envelope. The patient can be placed in either the prone or supine position. The prone position offers easier access to the fracture site, manipulation of the limb for reduction, and easier placement of hardware but requires flipping the patient if an anterolateral approach is required.
The incision is made along the border of the medial head of the gastrocnemius extending distally from the joint line for a length of 6–8 cm. The popliteal fossa is not crossed reducing the risk of contracture. The small saphenous vein is seen between the 2 heads of the gastrocnemius and protected. The fascia of the medial head of the gastrocnemius is incised and the muscle is retracted laterally. The pes anserinus tendons are seen in the proximal portion of the wound. This structure can be retracted medially, or if required for adequate visualization, released, and later repaired at the end of the procedure. Blunt dissection between the medial gastrocnemius and the pes anserinus is taken down to the popliteus, which is gently released from the tibia in a subperiosteal fashion to reveal the fracture. A submeniscal arthrotomy is rarely needed with the approach, as an anatomic reduction can be obtained with only visualization of the distal fracture line.
Reduction of the fracture is performed with extension and valgus force of the knee, axial traction, and an anteriorly directed force on the fracture fragment. The reduction is indirect and judged based on the apex of the fracture and on intraoperative fluoroscopy. The fracture pattern and location will determine the plating strategy. Most commonly, a “T” plate placed in an antiglide fashion will stabilize the fracture and prevent loss of reduction. A small fragment, nonlocking plate is typically best for this purpose. The gastrocnemius fascia and skin are then being closed in layers. Postoperative toe-touch weight bearing is used for 8–12 weeks with range of motion as tolerated. Patients typically tolerate this approach and hardware because of the excellent soft-tissue coverage.
Although numerous approaches have been described to access the posterior and medial tibial plateau, the Lobenhoffer approach offers a safe alternative to address posteromedial fractures often seen in high-energy tibial plateau fractures. It allows for direct visualization of the fracture fragment for accurate reduction and plating. The posterior neurovascular bundle is protected and the soft-tissue envelope allows for reliable wound healing. Utilization of this approach will maximize treatment of isolated posteromedial and bicondylar fractures of the tibial plateau.