Atypical femur fractures

Towards understanding how bisphosphonate-dependent alterations to nutrient canal integrity can contribute to risk for atypical femoral fractures: Biomechanical considerations and potential relationship to a real-world analogy

Bisphosphonates are a class of drugs which have shown good efficacy in the treatment of post-menopausal osteoporosis, as well as a good safety profile. However, side-effects such as risk for atypical femoral fractures (AFF) have appeared, leading to a decline in use of the drugs by many patients who would benefit from the treatment. While patient characteristics have contributed to improved understanding of risk factors, the mechanisms involved that explain AFF risk have not appeared. Recently, the possibility that the mechanism(s) involved drug-induced modification of cells of the nutrient canals of the femur and subsequent compromise in the bone matrix has been published. The present Hypothesis article builds on the concept presented earlier and expands into biomechanical considerations. An analogy of the mechanisms involved to a real-life scenario is also presented. While this analogy has limitations, consideration of the biomechanical implications of progressive alterations to defects presented by compromised nutrient canal-bone matrix also presents potential relationships with AFF risk.

Atypical periprosthetic femoral fractures after arthroplasty for fracture are at high risk of complications

It is difficult to investigate clinical features in a single-center study because atypical periprosthetic femoral fracture (APFF) is rare. This study aims to perform a nationwide survey of APFF to investigate the characteristics of this fracture and compare the clinical outcome with that of typical periprosthetic femoral fracture (typical PFF). A nationwide survey was performed asking for cooperation from 183 councilors of the Japanese Society for Fracture Repair. The subjects were patients with APFF injured between 2008 and 2017. The control group was comprised of patients with typical PFF of our facility injured in the same period. A total of 43 patients met the APFF definition. The control group was comprised of 75 patients with typical PFF. The rate of bisphosphonate use was significantly higher in the APFFs group than in the typical PFF group (62.8% and 32%, p < 0.02). The rate of cemented stem was significantly higher in the APFFs group than in the typical PFF group (30.2% and 6.7%, p < 0.001). In the patients with arthroplasty for hip fracture, multivariable logistic regression analyses showed that APFF was an independent risk factor of complications following the initial management (Odds ratio 11.1, 95% confidence interval 1.05–117.2, p = 0.045). However, no significant association between PFF and APFF was observed in the patients with arthroplasty for other hip diseases. The risk of complications was higher in the APFF group than in the typical PFF group in the patients with arthroplasty for fracture. When AFPP after arthroplasty for the fracture is suspected, it may be necessary to add not only internal fixation with a normal plate but also some additional treatment.

Nonunions of Bisphosphonate Fractures of the Femur: Presentation, Etiopathogenesis, Diagnosis, and Operative Treatment

Patients presenting with femoral fractures and long-term use of bisphosphonate treatment are at risk of developing a delayed union and/or nonunion as a result of the atypical metabolic activity prevailing at the fracture edges of the affected extremity. The treatment of these nonunions poses a serious challenge to orthopaedic surgeons worldwide and necessitates specialized techniques and materials to design a construct that will last a long period (greater than 6 months), while still allowing weight-bearing in this elderly population. Treatment options, timing of intervention, selection of implant, and the option of bone grafting are discussed to assist the clinician to make the right decisions in these complex clinical cases.

Socioeconomic and demographic determinants in the provision of assistance to elderly people with a fractured femur

Femur fracture affects the elderly with high morbidity and mortality. The purpose of the present study was to analyze the profile of the assistance given to the elderly who have femoral fractures, relating to their socioeconomic and demographic conditions, in the state of Paraná between the years 2008 to 2013. These relationships were obtained through factor analysis and the development and analysis of the following rates: PAE - the potential of primary health care to the elderly, whose variable was represented by the contribution of the elderly to the municipal GDP, PAP - the potential of the primary health care to the population, represented by GDP per capita and TE - treatment efficiency represented by the annual rate of fractures and annual rate of death per residence. The municipalities were classified according to the rate variation range. In relation to PAE, 10 municipalities were classified with low potential of care for the elderly, 357 with moderate potential and 32 had low potential. In relation to PAE, 12 municipalities were classified with low potential of primary care for the elderly, 303 with moderate potential and 84 had low potential. In relation to TE, 109 municipalities showed high treatment efficiency, 110 with moderate efficiency and 180 had low efficiency. Our conclusion was that the performance of the economy exerts significant influence on femoral fracture morbidity in the elderly.

Patients Receiving Parenteral Bisphosphonates for Malignant Disease and Having Developed an Atypical Femoral Fracture Are at Risk of Concomitant Osteonecrosis of the Jaw: An Evidence-Based Review

PURPOSE

The risk of developing concomitant medication-related osteonecrosis of the jaw (MRONJ) in patients who have sustained an atypical femoral fracture (AFF) in association with parental administration of a bisphosphonate osteoclastic inhibitor medication for malignant disease is unclear. Published data were searched to determine the prevalence of these concomitant adverse medication events, if any.

MATERIALS AND METHODS

A systematic review of published case series in the PubMed database was undertaken to ascertain the prevalence of patients having a concomitant history of AFF and MRONJ. The data were analyzed to provide prevalence rates of these events from the literature.

RESULTS

Two case series were identified that delineated the risk (25 and 33%, respectively) of concomitant development of MRONJ and AFF in recipients of parenteral bisphosphonate medication administered for malignant disease.

CONCLUSION

The published data suggest that approximately 30% of patients receiving parenteral bisphosphonates and having sustained an AFF could develop comorbid MRONJ.

Periprosthetic Atypical Femoral Fractures in Patients on Long-term Bisphosphonates: A Multicenter Retrospective Review

OBJECTIVES

To define the characteristics of periprosthetic atypical femoral fractures (PAFFs) in patients on long-term bisphosphonate treatment and to provide a guide to the diagnosis and long-term treatment of these patients based on the literature.

DESIGN

Multicenter retrospective review.

SETTING

Fifteen orthopaedic centers in the United States and Canada, including members of the Canadian Orthopaedic Trauma Society.

PATIENTS/PARTICIPANTS

Patients on long-term bisphosphonates who presented with either periprosthetic fractures or femoral fractures, over a 10-year period.

MAIN OUTCOME MEASUREMENTS

Time to union and complications.

RESULTS

Clinically significant differences were identified in time to union, mortality, and complications. There was a statistically significant difference in complications. Imaging review demonstrated identical features in both atypical femoral fractures (AFFs) and PAFFs.

CONCLUSIONS

This is the largest comparative case series reported on PAFFS and AFFs and provides compelling evidence that PAFFs in patients on long-term bisphosphonates are indeed a subset of periprosthetic fractures that exhibit atypical femoral fracture (AFF) characteristics. As such, these fractures pose serious diagnostic and management challenges to trauma and arthroplasty surgeons.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Atypical femoral fracture due to chronic use of bisphosphonates: case report

The causal relationship between chronic use of bisphosphonates and occurrences of atypical femoral fractures has not yet been established. Nonetheless, it is known that their chronic use is more related to fractures with a pattern differing from that of classical osteoporotic fractures. Atypical fractures are still rare events and the benefit from using bisphosphonates remains greater for prevention and treatment of osteoporosis. There are few studies guiding the diagnosis and management of these fractures, thus making it difficult to achieve better results. In this report, we present the case of an elderly patient with an atypical femoral fracture that was managed in accordance with guidance from the American Society for Bone and Mineral Research.

[Proximal femoral fractures in the elderly]

Proximal femoral fractures represent an increasing major healthcare problem due to the demographic changes in this aging population and are associated with the highest mortality among fractures in elderly patients after suffering insufficiency injuries (so-called fragility fractures). The main aim in the treatment of orthogeriatric patients who suffered from a proximal femoral fracture is the preservation of function and independency. Given the high prevalence of comorbidities in these patients, interdisciplinary and interprofessional approaches are required. The use of modern osteosynthesis procedures can provide an improved, individualized surgical treatment with early full weight bearing of the affected extremity. Another aspect is the accompanying geriatric treatment which is associated with a significant reduction of perioperative and postoperative complications. In addition to acute treatment, the organization of secondary fracture prevention is a crucial pillar of treatment. This article provides an overview of the essential elements of orthogeriatric trauma surgery in elderly patients following proximal femoral fractures.