Atypical and unclassifiable hip dislocation with capsule and labrum incarceration: a case report and review of the literature.

INTRODUCTION AND IMPORTANCE

Hip dislocations excluding the anterior, posterior or central variety have rarely been published. We report an atypical and unclassifiable dislocation of the hip joint with incarceration of the capsule and labrum. The aim of the presentation was to describe an uncommon type of hip dislocation with entrapment of the soft tissue.

CASE PRESENTATION

18-year-old patient, with no specific pathological history, was involved in a road traffic accident causing an unusual right hip joint displacement. After the first reduction, the control X-rays showed persistent enlargement of the joint line, strongly suggesting soft-tissue impingement. Computed tomography confirmed soft tissue entrapment in the anterior area between the head and the acetabulum. An Hueter approach carried out two weeks after the injury, revealed incarceration of the capsule and anterior labrum; which was released and repositioned. At 2-year follow-up, the patient complained of the pain and the Postel Merle d'Aubigné (PMA) score was 17. We observed the peritrochanteric calcifications but without signs of osteonecrosis femoral head.

CLINICAL DISCUSSION

Posterior and anterior hip dislocations are the main types. Forms excluding these types have rarely been reviewed. The last ones are usually surgical treatments, which help remove the obstacle, such as soft tissue or a bone fragment. However, the choice of approach depends on the displacement.

CONCLUSION

Atypical dislocation of the hip must be carefully reduced, due to the high risk of soft-tissue incarceration. An enlarged joint line on a control X-rays should lead to suspicion of a capsule or labrum interposition and a surgical strategy is required.