Radiological, clinical and functional outcome of children with traumatic hip dislocation: a multicenter review of 66 cases.

INTRODUCTION

Current understanding of the outcomes of post-traumatic hip dislocation (PHD) in pediatric patients is limited. The purpose of this study is to evaluate the radiologic, clinical, and functional outcomes of patients with PHD, whether isolated or associated with acetabular (ACF) or proximal femoral fractures (PFF), and to identify potential risk factors for adverse outcomes.

METHODS

This is a retrospective study of pediatric patients with PHD who were consecutively enrolled at three different institutions between 01/2016 and 06/2023. Patients were divided into three groups: PHD (PHD group), PHD with ACF (ACF group), and PHD with PFF (PFF group). Standard radiographs were used to classify each PHD and to identify the presence of other associated bone lesions. Clinical and functional outcomes were assessed using the Harris Hip Score (HHS). Avascular necrosis (AVN) was determined according to the Ratliff criteria. The association between outcome and associated injuries, age at trauma (≤ 10 versus > 11 years), traumatic mechanism (low versus high energy), reduction type (open versus closed), and direction of dislocation (posterior versus anterior) was evaluated.

RESULTS

Sixty-six cases of unilateral PHD (63 posterior and 3 anterior) were analyzed, consisting of 43 males and 23 females with a mean age of 10.7 years (1-18). Of these, 24 patients were ≤ 10 years old (36.4%), 16 of whom (66.7%) had low-energy trauma. Meanwhile, 42 patients were > 11 years old (63.6%), of which 26 had high-energy trauma (61.9%; p < 0.05). It was observed that patients in the PHD group were significantly younger than those in the ACF and PFF groups (p < 0.05). ACF group had 2/25 patients with misdiagnosed ACF > 3 weeks after injury (8%) and 3/25 with concomitant ACF and PFF (12%), and PFF group had 4/12 patients with AVN (33.3%). Most patients had a favorable mean HHS score, being 97.3 for the PHD group, 93.8 for the ACF group, and 93.6 for the PFF group.

CONCLUSION

The outcome of PHD is worse in patients with AVN secondary to PFF, simultaneous ACF and PFF, misdiagnosed ACF, high-energy trauma, and older age at the time of injury. Advanced imaging, such as CT scan or MRI is necessary to rule out ACF in isolated dislocations. Timely diagnosis and treatment of these lesions usually result in a favorable outcome.

LEVEL OF EVIDENCE: III.