Review Question - QID 220390

This patient has a medial split tibial plateau fracture-dislocation (Schatzker IV). The main fracture fragment is posteromedial as shown in Figure B, and would be best accessed through the posteromedial approach, between the pes anserinus and the medial head of the gastrocnemius (Answer 2).

Tibial plateau fractures are periarticular injuries of the proximal tibia and are frequently associated with soft tissue damage. Two common classification systems that have been developed for tibial plateau fractures are Schatzker and Hohl and Moore. Both of these systems help providers assess the severity of injury and soft tissue damage as well as the location of the fracture(s). The vector of injury, amount of energy applied, and bone quality all determine the fracture pattern. Medial tibial plateau fracture-dislocations (Schatzker IV) are frequently associated with high-energy mechanisms and soft tissue injuries. Soft tissue injuries such as medial meniscus tears are most commonly associated with medial tibial plateau fractures. The goals of treatment for operative fixation center around the restoration of anatomic alignment of the articular surface as well as mechanical stability of the joint. These goals can be achieved by utilizing posteromedial, anterolateral, direct posterior, posterolateral, and medial approaches.

Hu et al. conducted a cadaveric study investigating the differences between the posterolateral and posteromedial approaches to tibial plateau fractures. They found the anterior tibial artery (ATA) courses through the interosseous membrane fissure 49.3 ± 5.6 mm distal to the lateral joint line, and the distance to the fibular head was 37.7 ± 7.2 mm. The diameter of the anterior NV bundle was found to be 10 mm. The posterolateral tibial plateau was, on average, 61.7% shielded by the fibular head from the posterior view. They conclude that the posteromedial approach may be safer, but also presents a limited amount of direct visualization of the articular surface.

Cardon et al. conducted a cadaveric study in 10 patients comparing the accessible area of the posterior tibial plateau in the standard posteromedial (PM) approach (without tenotomy) and the modified posteromedial approach with a medial gastrocnemius tenotomy. The results demonstrated an accessible area of 1,774 mm^2 and 2,350 mm^2 for the standard and modified PM approaches, respectively (p< 0.0001). A linear distance of 38 mm and 57 mm (p<0.00001) was achieved between the standard and modified PM approaches, respectively. They concluded that the modified PM approach significantly improves surgical access to the posterior tibial plateau and serves as an alternative approach to the more dangerous posterolateral plateau fractures.

Figure A is an AP radiograph of a right knee demonstrating a medial split (Schatzker IV) tibial plateau fracture-dislocation. Figure B is an axial view of a CT scan of the same knee demonstrating a large posteromedial tibial plateau fracture. Illustration A is an anatomic diagram outlining the posteromedial approach to the tibial plateau.

Incorrect Answers:
Answer 1: The posterolateral approach poses an increased risk of injury to neurovascular structures and doesn't provide as much access to the posterior medial plateau when compared to the posteromedial approach.
Answer 3: The anterolateral approach would not provide adequate access to the posteromedial tibial plateau.
Answers 4 and 5: The anteromedial and medial approaches would not provide adequate reduction of this fracture since the fragment is largely posterior and medial.