The tibial plafond is the distal articular surface of the tibia that forms the roof of the ankle mortise, articulating with the superior dome of the talus. It is a concave surface measuring approximately 25 x 40 mm that distributes axial load across the ankle joint. The articular cartilage of the plafond is thinnest centrally and thicker peripherally, complementing the convex talar dome. The plafond is supported by the subchondral bone plate of the distal tibial metaphysis.
Pilon fractures are high-energy fractures of the tibial plafond from axial compression (falls from height, motor vehicle accidents), producing comminuted articular surface disruption. The degree of articular fragmentation, soft tissue injury, and metaphyseal impaction determines the staging and treatment strategy. Anatomic reduction of the articular surface is the surgical goal, though even perfect reduction does not prevent post-traumatic ankle arthrosis in severe fractures. Primary ankle arthrodesis is considered in elderly patients with severe comminution.
High-energy axial loading shatters the tibial plafond articular surface, producing comminuted intra-articular fractures requiring staged management: initial spanning external fixation allowing soft tissue recovery, followed by definitive plate fixation with articular surface restoration after 7-14 days.
Despite anatomic reduction, severe pilon fractures destroy cartilage and subchondral bone of the plafond, producing progressive ankle pain and stiffness from post-traumatic arthrosis requiring ankle arthrodesis or total ankle replacement.
