The objectives of this prospective study were to investigate the value of the immediate closed reduction following fractures of the thoracolumbar and lumbar region. To reach that goal we performed a two stage CAT scan procedure before and after the reduction maneuver in a distinct patient population. The aim was not only to investigate the biomechanical process but also to evaluate and describe certain fracture types which have a good prognosis due to closed reduction according to posttraumatic spinal stenosis because of protruding posterior wall fragments and those who fail, respectively.