Prognostic factors after a traumatic hip dislocation. A long-term retrospective study.

Introduction: Traumatic hip dislocations can have devastating complications such as osteoarthritis or osteonecrosis. The aim of this study was to identify the variables and prognostic factors associated with clinical and radiological outcome after a traumatic hip dislocation at long-term follow-up.

Material And Methods: A review was performed of all dislocations and fracture-dislocations of the hip from January 1999 to December 2012. A computed tomography scan was performed after reduction in all cases. The Harris Hip Score and modified Merle-d'Aubigné-Postel method were used for clinical evaluation and radiological assessment was performed according to the Thompson and Epstein classification.

Results: There were 30 cases in 29 patients with a mean follow-up of 11 years (range, 4-17). The great majority were simple dislocations (21; 70%) vs. complex dislocations (9; 30%). Closed reduction was performed in less than 6h in all except one case (29; 96.7%). All of the patients with simple dislocations had an excellent outcome without radiological signs of osteoarthritis at the end of the follow-up (P<.01). Overall, arthritic signs had developed in 4 patients (13.3%) and avascular necrosis was noted in 3 patients (10%). Five patients with intraarticular fragments were treated non-operatively, and 3 of them developed arthritic changes (P<.05).

Conclusion: Our study suggests that complex dislocations are associated with poorer functional and radiological outcomes than simple dislocations. We also found a strong association between intraarticular fragments and osteoarthritis, so surgical fragment removal could be considered in these cases.