Congenital knee dislocation. Coloured X-ray of the dislocated and twisted knee of a female baby. The lower leg bones have twisted 180 degrees to the femur (at top). The tibia (shin bone), the thicker lower leg bone, should be on the right of the fibula (thinner lower leg bone). The bones on either side of the knee joint should also line up. Dislocation can occur due to injury such as a hard knock or twisting movement, or may be a congenital (present from birth) abnormality such as here. It can cause considerable pain. Treatment is by manual manipulation to relocate the bones and they may have to be immobilised to set them in place. For images showing the manipulation of the leg bones to their correct position, see M330/1561 and M330/1562.