Obturator dislocation of the hip with ipsilateral femoral neck fracture: A case report

Prognostic and therapeutic interest of a new classification in inferior hip dislocation: a systematic review of the literature

INTRODUCTION

Reported cases of inferior dislocation in the literature are found under several names (inferior, anteroinferior, obturator, or erecta), which may be source of confusion. The purpose of this comprehensive review of the literature is to collect as many cases of inferior dislocation as possible to determine better therapeutic strategies, outcome after reduction, complications, and prognostic factors.

METHODS

In April 2020, a literature search was performed in Pubmed, Medline, Scopus, Cochrane, and Embase databases. The MeSH keywords were "OBTURATOR DISLOCATION HIP" or "ANTERIOR DISLOCATION HIP" or "INFERIOR DISLOCATION HIP." Authors independently selected articles that met the selection criteria, with no time limit.

RESULTS

Out of the 97 articles selected, there were 119 cases of primary inferior hip dislocations. This review of the literature has allowed us to differentiate 3 radiographic subtypes of inferior dislocations, which correspond to 3 different anatomical positions of the femoral head: "obturator" dislocation, "proximal anterior-inferior" dislocation, and "distal anterior-inferior" dislocation. Our subtype classification yielded 39 obturator subtype inferior dislocations (32.8%), 66 proximal anteroinferior subtypes (55.4%), and 14 distal anteroinferior (11.8%). The obturator subtype is at risk of reduction failure and femoral neck fracture during the reduction manoeuver.

CONCLUSIONS

Our study identified 3 subtypes with different prognosis, with obturator and distal anteroinferior dislocations having a poorer prognosis because of their pre- and post-reduction complications. We were unable to determine the correct manoeuver to reduce inferior dislocations without taking the risk of femoral neck fracture, but each of these subtypes may require a different manoeuver.

Traumatic obturator dislocation of the hip joint: About 2 cases and review of the literature

Introduction

Traumatic dislocation of the hip is a serious lesion, and its obturator variety is rarely reported. It always reflects a high-energy trauma and represents a therapeutic emergency that requires a reduction in less than 6 h due to the risk of aseptic necrosis of the femoral head in the long term.

Case report

We reported 2 cases of hip obturator dislocation in patients aged 21 and 45 years respectively, which occurred following a road accident, received for pain and functional impairment of the hip, and in a typical attitude with hip flexion, abduction, rotation and knee flexion with no downstream limb vascular-nervous injury. The emergency reduction in <6 h, in two cases, followed by functional treatment by offloading for 8 weeks and support of the limb with the resumption of walking had been authorized at 3 months with a return to sport at 16 weeks; made it possible to obtain satisfactory results at 18 months of follow-up, with an absence of a functional gene, stiffness and without signs of necrosis of the femoral head.

Discussion and conclusion

Traumatic obturator dislocation of the hip constitutes serious lesions and requires early and appropriate management, reduced to closed focus, treated functionally give excellent results in the medium term. The patient must be carefully monitored over the long term and be warned of the risks he runs.

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Traumatic obturator hip dislocation is a serious lesion and rarely reported.

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Therapeutic emergency requires a reduction < 6 h because the long-term prognosis of the femoral head is strongly linked.

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Simple unloading of the limb without transosseous traction provides excellent medium-term outcomes.

Femoral neck fracture combined with anterior dislocation of the femoral head: injury mechanism and proposed novel classification

BACKGROUND

Femoral neck fracture combined with anterior dislocation of the femoral head is very rare. To our knowledge, there is no classification system yet for this rare form of injury, and the injury mechanism of femoral neck fracture combined with obturator head dislocation has not been described in the literature. In this study, we systematically reviewed the literature and the cases treated in our hospital, and identified and classified all injury types according to the injury mechanism of femoral neck fracture combined with anterior dislocation of the femoral head. Further, based on the experience of treating a patient with femoral neck fracture and obturator dislocation of the femoral head, a theoretical hypothesis was proposed for the injury mechanism of this rare type of injury.

METHODS

A comprehensive search was conducted on PubMed, WOS, CNKI database. These fractures were classified according to the dislocation site and injury mechanism (one injury or two injuries).

RESULTS

1891 articles were initially identified through PubMed and other databases, and after bibliographic research, study screening, and removing duplicates, 1455 articles were selected. After applying the exclusion criteria, a total of 18 full-text articles describing femoral neck fractures combined with anterior dislocation of the femoral head. Different dislocation sites have different injury mechanisms. Our classification system, to the best of the authors' knowledge, allowed us to include all types of femoral neck fractures combined with anterior dislocation of the femoral head from the literature. According to the proposed classification system, the morphological features of femoral neck fracture combined with anterior dislocation of the femoral head can be accurately conveyed between doctors.

CONCLUSIONS

All injury patterns can likely be identified using the proposed classification system. This can help avoid confusion in the nomenclature of femoral neck fractures combined with anterior dislocation of the femoral head and help surgeons to more accurately detect lesions, thereby guiding surgical treatment.

Total Hip Arthroplasty to Treat Chronic Native Hip Obturator Dislocation: A Case Report

CASE

A 37-year-old woman presented with a rare chronic dislocation of her native right hip where the head of the femur was incarcerated in the obturator foramen of her pelvis. After optimization of sociomedical factors, she underwent successful total hip arthroplasty.

CONCLUSION

Total hip arthroplasty is a viable treatment option for the chronic incarcerated obturator hip dislocation.

Intrapelvic Femoral Head Dislocation without Associated Proximal Femur Fracture: A Case Report and Description of Closed Reduction Technique

Traumatic hip dislocations are potentially devastating injuries, especially in young patients, and require emergent orthopedic treatment. Given the significant amount of energy required to cause these injuries, a high index of suspicion is necessary to identify related injuries. The associated injuries, direction of dislocation, and time between injury and reduction represent the known prognostic factors, based on limited available research. Intrapelvic hip dislocations represent an uncommon variant of the traumatic hip dislocation, with all previously reported cases involving ipsilateral proximal femur fractures. We present a case of intrapelvic femoral head dislocation without an associated proximal femur fracture, as well as the maneuvers used to treat the patient via a closed reduction.

Obturator dislocation of the femoral head combined with ipsilateral femoral neck and pubic fractures: A rare case report

RATIONALE

Obturator dislocation of the femoral head combined with ipsilateral femoral neck and pubic fracture is a rare injury. We used cannulated screws combined with a femoral neck medial plate for the first time to treat this type of injury and achieved good follow-up results.

PATIENT CONCERNS

The patient was hospitalized due to an accident resulting in swelling and deformity accompanied by limited mobility of the right hip and left knee.

DIAGNOSES

X-ray examination and computed tomography confirmed that the patient suffered from right hip obturator dislocation, femoral head and neck fracture, pubic fracture, as well as open fracture of the left femoral shaft.

INTERVENTIONS

Open reduction and internal fixation with cannulated screws and a medial support plate of the femoral neck were performed for the right hip obturator dislocation, femoral head and neck fracture, and the pubic fracture. Artificial bone grafting was performed to support the femoral head defect. Debridement and the second phase of internal fixation were executed to cure the open fracture of the left femoral shaft.

OUTCOMES

The patient was followed-up for 6 months and showed good hip function. X-ray examination and computed tomography indicated that the fractures healed well without fracture displacement or loosening of the implants. Meanwhile, there were no signs of femoral neck valgus and femoral head necrosis observed.

LESSONS

The combination of cannulated screws and medial support plate was suggested for the treatment of hip obturator dislocation and femoral head and neck fracture. Furthermore, partial weight loading exercise should be performed promptly to reduce the risk of muscular atrophy and myasthenia.

Iatrogenic Obturator Hip Dislocation with Intrapelvic Migration

Obturator hip dislocations are rare, typically resulting from high-energy trauma in native hips. These types of dislocations are treated with closed reduction under sedation. Open reduction and internal fixation may be performed in the presence of associated fractures. Still rarer are obturator hip dislocations that penetrate through the obturator foramen itself. These types of dislocations have only been reported three other times in the literature, all within native hips. To date, there have been no reports of foraminal obturator dislocations after total hip arthroplasty. We report of the first periprosthetic foraminal obturator hip dislocation, which was caused iatrogenically during attempts at closed reduction of a posterior hip dislocation in the setting of a chronic greater trochanter fracture. Altered joint biomechanics stemming from a weak hip abductor mechanism rendered the patient vulnerable to this specific dislocation subtype, which ultimately required open surgical intervention. An early assessment and identification of this dislocation prevented excessive closed reduction maneuvers, which otherwise could have had detrimental consequences including damage to vital intrapelvic structures. This case report raises awareness to this very rare, yet potential complication after total hip arthroplasty.