Classification of posterior fracture dislocation of the hip joint: a modification of the Thompsen Epstein classification.

The purpose of this paper was to describe a classification of posterior fracture dislocations of the hip joint, which would highlight the important aspects of managing this injury and more closely correlate with the prognosis. During the period from July 1994 to September 1997, the senior author operated on 60 posterior fracture dislocations of the hip joint. The results of the surgery were scored according to our ability to accurately anatomically reconstruct the acetabulum. We found that the degree of comminution was a greater determent of whether we could achieve an anatomical reconstruction than the presence of an associated acetabular floor fracture. Epstein showed conclusively that type II and III injuries have significantly different outcomes, but then grouped them together as type IV injuries if there was an associated floor fracture. We felt it more appropriate to continue with Epstein's fundamental feature of ascribing a grade according to the comminution and subdivided his type IV injuries.