Lateral tibial plateau

The lateral tibial plateau is the upper, outer portion of the proximal tibia that articulates with the lateral femoral condyle. It is characterized by several key anatomical features:

• Shape and Contour: The lateral plateau is generally more convex and smaller in the anteroposterior dimension compared to the medial plateau, which is larger and more concave. This convexity contributes to the static stability of the knee and influences the path of the lateral femoral condyle during knee motion, particularly in the "screw home" mechanism.

• Articular Surface: The articular cartilage of the lateral plateau is thinner than that of the medial plateau. The subchondral bone beneath the lateral plateau has a greater posterior slope (mean ~7.5°) compared to the medial plateau (mean ~5.2°), which is relevant for knee biomechanics and risk of anterior cruciate ligament (ACL) injury.

• Boundaries and Landmarks: The lateral plateau is bordered laterally by the proximal tibiofibular joint and the fibular head, anteriorly by the tibial tubercle, and medially by the intercondylar eminence (tibial spine). The posterolateral corner is a frequent site of fracture and is anatomically complex, involving the lateral meniscus, popliteus tendon, and attachments of the lateral collateral ligament.

• Meniscal Relationship: The lateral meniscus covers a larger portion of the lateral plateau than the medial meniscus does on the medial side, and the anterior horn of the lateral meniscus is sometimes detached for surgical exposure in complex fracture cases.

• Fracture Patterns: The lateral plateau is more commonly involved in tibial plateau fractures, with recurrent patterns including lateral split fragments and comminution extending into the tibial spine and lateral condyle.