The pilon fracture is a comminuted fracture of the distal tibia. The fracture consists of a long oblique fracture extending medial to lateral as well as a fracture extending to the tibiotalar articular surface. It results from an axial loading injury, with impaction of the talus upon the tibial plafond. Because of the severity of the fracture and its intraarticular involvement, posttraumatic arthritis is a common sequela.
Lateral radiograph of the ankle. There is a comminuted fracture of the distal tibia. 
Mortise view of the ankle. This demonstrates the extension of the fracture line to the articular surface of the tibiotalar joint. 
AP radiograph of the ankle. This shows the fracture lines through the distal tibia.