Unstable pelvic ring fractures, during the first days post-trauma, are potentially life-threatening lesions. In the long term, these lesions can lead to important functional deficits. 44 patients with an unstable pelvic ring fracture were included in this study. 35 of which were reevaluated after an average of 19 months. It is demonstrated that a rapid stabilisation of the pelvic ring fracture decreases the mortality and that after surgical intervention, the M. Tile Fracture Classification is of prognostically significant value with respect to the functional outcome. Type B fractures, which are only rotationally unstable, have a better final functional result compared with the Type C fractures with rotational and vertical instability. There exists a significant difference between the two groups.