Trochanteric Femoral Fracture Around a Birmingham Hip Resurfacing Prosthesis: A Case Report and Review of the Literature

Strategies for fixation of periprosthetic fragility fractures of the neck of femur below a well-functioning hip resurfacing arthroplasty: A case-series

Introduction

Metal-on-metal Hip Resurfacing (HR) was performed in many young individuals as it conserved bone stock and had low wear rates, before it became less popular due to the detection of Adverse Reactions to Metal Debris. As such, many patients in the community have well-functioning HRs and as they age, the incidence of fragility fractures of the neck of femur around the existing implant is expected to increase. These fractures are amenable to surgical fixation as adequate bone stock remains in the head of the femur and the implants are well fixed.

Case-series

We present a series of six cases which were treated by fixation using locked plates (3), dynamic hip screws (2) and cephalo-medullary nail (1). Four cases achieved clinical and radiographic union with good function. One case had a delayed union, though union was finally achieved at 23 months. One case had an early failure necessitating revision to a Total Hip Replacement after 6 weeks.

Discussion

We highlight the geometrical principles of placing fixation devices under an HR femoral component. We have also conducted a literature search and present details of all case reports to date.

Conclusion

Fragility per-trochanteric fractures under a well-fixed HR with good baseline function are amenable to fixation using a variety of methods including large screw devices that are commonly used in this location. Locked plates including variable angle locking designs should be kept available if needed.

Fixation and Implant Retention of Extracapsular Femoral Neck Periprosthetic Fractures Around Hip Resurfacing Arthroplasty - A Case Series

BACKGROUND

Extracapsular femoral neck fractures in the presence of a resurfacing hip arthroplasty (RHA) appear to be independent of suboptimal technique during the initial implantation of the RHA and present with a similar etiology as native hip fractures - that is, a fragility fracture related to pathological or age-related osteoporosis, as a consequence of trauma. In the presence of a well-fixed and previously well-functioning RHA, the options for management include revision arthroplasty or open reduction and internal fixation (ORIF). In the absence of loosening through mechanisms of wear, infection, metallosis, or suboptimal prosthesis positioning, many authors have advocated ORIF with implant retention. However, there is often debate regarding the use of total hip arthroplasty in these cases.

CASE SERIES

The authors conducted a thorough assessment of the literature followed by a retrospective review of outcomes for three patients treated by ORIF with implant retention for extracapsular femoral neck fractures around a RHA, using a standardized technique. All patients were independently mobile and active with well-fixed and well-functioning RHAs before the date of injury. All patients suffered low-energy trauma resulting in the fracture. There were no intraoperative or perioperative complications. All patients achieved full weight-bearing status and independent mobility. Two patients achieved radiographic union and returned to full range of movement and independent mobilization comparable to their preoperative state. One patient was lost to follow-up.

CONCLUSION

The authors believe that fixation of extracapsular proximal femoral fractures distal to a well-fixed, well-functioning RHA is a good management option in an independent and active patient. A higher level of evidence is needed to investigate the surgical management options of these injuries comparing osteosynthesis with revision arthroplasty.

Risk assessment of resurfacing implant loosening and femur fracture under low-energy impacts taking into account degenerative changes in bone tissues. Computer simulation

BACKGROUND AND OBJECTIVE

Degenerative diseases of the musculoskeletal system significantly reduce the quality of human life. Hip resurfacing is used to treat degenerative diseases in the later stages. After surgery, there is a risk of endoprosthesis loosening and low-energy fracture during daily physical activity. Computer modeling is a promising way to predict the optimal low-energy loads that do not lead to bone destruction. This paper aims to study numerically the mechanical behavior of the proximal femur, amenable to degenerative changes and subjected to hip resurfacing under low-energy impact equivalent to physiological loads.

METHODS

A numerical model of the mechanical behavior of the femur after hip resurfacing arthroplasty under low-energy impacts equivalent to physiological loads is presented. The model is based on the movable cellular automaton method (discrete elements), where the mechanical behavior of bone tissue is described using the Biot poroelasticity accounting for the presence and transfer of interstitial biological fluid.

RESULTS

For the first time, it is shown that a poroelastic model allows predicting the service life of endoprostheses, taking into account the individual characteristics of the bone tissues amenable to various degenerative diseases. The obtained results indicate that the changes in the bone properties have a significant influence on the critical forces corresponding to the first appearance of microcracks and the fracture formation. At the same time, their effect on the type of fracture is negligible. A much more impact on the type of fracture has the kinematic and dynamic conditions of the exposure.

CONCLUSIONS

The obtained results show the promise of using the proposed model for predicting the operational resource of resurfacing endoprostheses, taking into account the physiological features of the structure of the patient's bone tissues.

Periprosthetic Intertrochanteric Fracture between Hip Resurfacing and Retrograde Nail

Periprosthetic femur fractures present a growing worldwide challenge for orthopaedic surgeons. Fractures around a hip resurfacing implant create unique management problems. When considering fixation, there can be limited options for ideal stabilization and some require creative constructs. We present an interesting case of a periprosthetic intertrochanteric femur fracture between a hip resurfacing implant and retrograde intramedullary nail.

Routine Fracture Fixation for a Periprosthetic Hip Fracture Below Birmingham Hip Resurfacing: A Case Report

CASE

We present a case of a 56-year-old man who sustained a basal cervical periprosthetic fracture around a well-fixed metal-on-metal hip resurfacing arthroplasty (MoMHRA). Although several fixation methods have been described, there seems to be no consensus about the optimal fixation method for fractures around MoMHRAs. This fracture could be regarded as a Vancouver type-B1 or -C periprosthetic fracture, so we successfully treated our patient in a standard way with a dynamic hip screw (DHS) and one cannulated hip screw.

CONCLUSION

We describe DHS fixation as a successful treatment option for periprosthetic hip fractures around well-fixed MoMHRA.

Acetabular Fracture Around a Birmingham Hip Resurfacing Prosthesis: A Case Report

CASE

A traumatic displaced transverse periprosthetic acetabular fracture around a well-functioning Birmingham hip resurfacing prosthesis was treated with open reduction and internal fixation. The acetabular component was found to be well-fixed intraoperatively and did not require revision. The patient recovered with excellent clinical and radiographic results at the 1-year follow-up with a Harris Hip Score of 94.

CONCLUSIONS

Internal fixation, rather than revision arthroplasty, offers acceptable outcomes in patients with periprosthetic acetabular fractures about well-fixed hip resurfacing prostheses. Radiographic and intraoperative assessment of stability is critical in guiding treatment.