There are four different types of fractures that can occure in the knee, such as Distal femoral, Patellar, Tibial, and Fibular Fractures.
Distal Femoral Fractures occure on the femor, these are a result of axial loading and combination of valgus and varus stress and rotation.
Patellar Fracutres are brought on by direct force and occasionally, indirect forces such as a quadriceps contraction. Most patellar fractures, radiographic diagnosis is straight forward. These patellar fractures are demostrated on radiography images ("sunrise" views).
Tibial fractures occure on the tibia as a tibial plateau fracture that is a vertical compression, varus or valgus forces, and or twisting.
Fibular fractures occur on the head or neck of the fibula. These fractures are caused by a direct blow, varus force, valgus force or twisting force.