Teriparatide, vitamin D, and calcium healed bilateral subtrochanteric stress fractures in a postmenopausal woman with a 13-year history of continuous alendronate therapy

Emilin2 marks the target region for mesenchymal cell accumulation in bone regeneration

BACKGROUND

Regeneration of injured tissue is dependent on stem/progenitor cells, which can undergo proliferation and maturation processes to replace the lost cells and extracellular matrix (ECM). Bone has a higher regenerative capacity than other tissues, with abundant mesenchymal progenitor cells in the bone marrow, periosteum, and surrounding muscle. However, the treatment of bone fractures is not always successful; a marked number of clinical case reports have described nonunion or delayed healing for various reasons. Supplementation of exogenous stem cells by stem cell therapy is anticipated to improve treatment outcomes; however, there are several drawbacks including the need for special devices for the expansion of stem cells outside the body, low rate of cell viability in the body after transplantation, and oncological complications. The use of endogenous stem/progenitor cells, instead of exogenous cells, would be a possible solution, but it is unclear how these cells migrate towards the injury site.

METHODS

The chemoattractant capacity of the elastin microfibril interface located protein 2 (Emilin2), generated by macrophages, was identified by the migration assay and LC-MS/MS. The functions of Emilin2 in bone regeneration were further studied using Emilin2-/- mice.

RESULTS

The results show that in response to bone injury, there was an increase in Emilin2, an ECM protein. Produced by macrophages, Emilin2 exhibited chemoattractant properties towards mesenchymal cells. Emilin2-/- mice underwent delayed bone regeneration, with a decrease in mesenchymal cells after injury. Local administration of recombinant Emilin2 protein enhanced bone regeneration.

CONCLUSION

Emilin2 plays a crucial role in bone regeneration by increasing mesenchymal cells. Therefore, Emilin2 can be used for the treatment of bone fracture by recruiting endogenous progenitor cells.

Geriatric trauma: there is more to it than just the implant!

Geriatric trauma continues to rise, corresponding with the continuing growth of the older population. These fractures continue to expand, demonstrated by the incidence of hip fractures having grown to 1.5 million adults worldwide per year. This patient population and their associated fracture patterns present unique challenges to the surgeon, as well as having a profound economic impact on the health care system. Pharmacologic treatment has focused on prevention, with aging adults having impaired fracture healing in addition to diminished bone mineral density. Intraoperatively, novel ideas to assess fracture reduction to facilitate decreased fracture collapse have recently been explored. Postoperatively, pharmacologic avenues have focused on future fracture prevention, while shared care models between geriatrics and orthopaedics have shown promise regarding decreasing mortality and length of stay. As geriatric trauma continues to grow, it is imperative that we look to optimize all phases of care, from preoperative to postoperative.

The effect of teriparatide on patients with atypical femur fractures: a systematic review and meta-analysis

INTRODUCTION

Bisphosphonates (BPs) are one of the most often used drugs to lower fracture risk in osteoporosis patients; nonetheless, BPs have been linked to atypical femoral fracture (AFF). Teriparatide (TPTD) is a parathyroid hormone analogue and anabolic drug that may accelerate fracture repair. TPTD has been considered as a possible treatment for AFF, particularly those caused by BP use. We evaluate the effect of TPTD on AFF in this systematic review and meta-analysis.

MATERIALS AND METHODS

A thorough search of: Web of Science, Scopus, PubMed, and Cochrane was conducted on August 2, 2023. Trials evaluating the effect of TPTD on the incidence of: complete bone healing, non-union, early and delayed bone union, progression of incomplete AFF to complete AFF, and time to bone union were included. Using Review Manager (RevMan) version 5.4, the risk ratio (RR) and mean difference (MD) with the corresponding 95% confidence interval (CI) were estimated for dichotomous and continuous outcomes, respectively. The Newcastle-Ottawa Scale was used to assess the quality of studies.

RESULTS

Eight studies met the eligibility criteria and were included in our analysis. TPTD significantly increased the incidence of early bone union (RR = 1.45, 95% CI [1.13, 1.87], P = 0.004) and time to bone union (MD = -1.56, 95% CI [-2.86, -0.26], P = 0.02) compared to the control group. No significant differences were observed in terms of complete bone healing (RR = 1.09, 95% CI [0.99, 1.13], P = 0.12), non-union (RR = 0.48, 95% CI [0.22, 1.04], P = 0.06), and progression of incomplete AFF to complete AFF (RR = 0.27, 95% CI [0.04, 1.97], P = 0.19).

CONCLUSIONS

TPTD is an effective therapy for enhancing and hastening healing following AFF, particularly in postoperative settings. Future large randomized clinical trials are needed to confirm or dispute the results.

Modulation of the vitamin D/vitamin D receptor system in osteoporosis pathogenesis: insights and therapeutic approaches

Osteoporosis is a prevalent bone disorder characterized by low bone mineral density (BMD) and deteriorated bone microarchitecture, leading to an increased risk of fractures. Vitamin D (VD), an essential nutrient for skeletal health, plays a vital role in maintaining bone homeostasis. The biological effects of VD are primarily mediated through the vitamin D receptor (VDR), a nuclear receptor that regulates the transcription of target genes involved in calcium and phosphate metabolism, bone mineralization, and bone remodeling. In this review article, we conduct a thorough literature search of the PubMed and EMBASE databases, spanning from January 2000 to September 2023. Utilizing the keywords "vitamin D," "vitamin D receptor," "osteoporosis," and "therapy," we aim to provide an exhaustive overview of the role of the VD/VDR system in osteoporosis pathogenesis, highlighting the most recent findings in this field. We explore the molecular mechanisms underlying VDR's effects on bone cells, including osteoblasts and osteoclasts, and discuss the impact of VDR polymorphisms on BMD and fracture risk. Additionally, we examine the interplay between VDR and other factors, such as hormonal regulation, genetic variants, and epigenetic modifications, that contribute to osteoporosis susceptibility. The therapeutic implications of targeting the VDR pathway for osteoporosis management are also discussed. By bringing together these diverse aspects, this review enhances our understanding of the VD/VDR system's critical role in the pathogenesis of osteoporosis and highlights its significance as a potential therapeutic target.

Atypical femur fracture associated with common anti-osteoporosis drugs in FDA adverse event reporting system

Atypical femur fracture (AFF) is a rare but catastrophic adverse event first reported in the long-term use of alendronate, one of the most commonly used drugs for osteoporosis currently. However, further evidence is needed to learn more regarding other common anti-osteoporosis drugs and the risk for AFF. In this study, reports of AFF were identified from Food and Drug Administration Adverse Event Reporting System database. Disproportionality analyses were performed to examine the reporting odds ratio (ROR), information component (IC) and adjusted ROR (adj. ROR) signals for AFF for common anti-osteoporosis drugs. A total of 1692 unique AFF reports were identified. The disproportionality signals (the lower bound of 95% confidence interval > 1 for ROR and adjusted ROR, and > 0 for IC) were detected for alendronate, denosumab, pamidronate, risedronate, zoledronate, ibandronate, and teriparatide while no signal was detected for raloxifene, abaloparatide, and romosozumab. When restricted in patients with osteoporosis, the disproportionality signals were still detected for alendronate, pamidronate, risedronate, denosumab, and ibandronate. Our results suggest that alendronate has the largest risk signal, while the risks varied among different bisphosphonates. In addition, denosumab was found statistically associated with AFF in both the entire database and patients with osteoporosis.

Bilateral Atypical Femoral Fractures after Bisphosphonate Treatment for Osteoporosis: A Literature Review

INTRODUCTION

This literature review aimed to investigate the incidence, anatomical concerns, etiology, symptoms, diagnostic tools, management, and prognosis of bisphosphonate (BP)-associated bilateral atypical femoral fractures (AFFs).

METHODS

The PubMed, Cochrane Library, Web of Sciences, and CINAHL databases were searched up to 20 March 2022. All cases of bilateral AFFs were included, excluding those without any bisphosphonate treatment information and those in which the femoral fracture did not precisely fit into the diagnostic criteria for AFF.

RESULTS

We identified 43 patients with bilateral AFFs associated with BP use and conducted a comprehensive analysis. Among 43 patients, 29 (67%) had prodromal symptoms. Regarding the simultaneity of fracture, 21 cases (49%) occurred simultaneously, and 22 cases (51%) occurred sequentially. Alendronate was the most commonly used BP treatment (59%). Regardless of the medication type, BP intake duration was more than 5 years in 77%. The initial diagnosis was performed using X-rays in all cases. A total of 53% of patients had complete fractures, and all patients underwent surgical treatment. Among the remaining patients with incomplete fractures, 18% and 29% received surgical and medical treatments, respectively. After BP discontinuation, teriparatide was most commonly used (63%).

CONCLUSIONS

The careful evaluation of relevant imaging findings in patients with thigh/groin pain allows the identification of early incomplete fractures and timely management. Since the rate of contralateral side fractures is also high, imaging studies should be performed on the asymptomatic contralateral side.

A brief review and clinical evidences of teriparatide therapy for atypical femoral fractures associated with long-term bisphosphonate treatment

The risk of bisphosphonate (BP)-associated atypical femur fracture (AFF) has markedly increased over recent decades due to suppression of bone turnover, accumulation of structural micro-damage and reduction of bone remodeling consequent to long-term BP treatment. These medications further delay bone union and result in challenging clinical management. Teriparatide (TPTD), a synthetic human parathyroid hormone, exhibits unique anabolic effects and can increase bone remodeling and improve bone microarchitecture, further promoting fracture healing and reducing the rate of bone non-union. In this study, we briefly define AFF as well as the effects of BPs on AFFs, detailed the role of TPTD in AFF management and the latest clinical therapeutic findings. We have confirmed that TPTD positively promotes the healing of AFFs by reducing the time to bone union and likelihood of non-union. Thus, teriparatide therapy could be considered as an alternative treatment for AFFs, however, further research is required for the establishment of effective clinical guidelines of TPTD use in the management of AFF.

Factors affecting healing and progression of conservatively treated incomplete atypical femoral fractures: retrospective observational study

INTRODUCTION

Incomplete atypical femoral fractures (iAFF) may occur with prolonged bisphosphonate usage. Factors influencing iAFF healing and progression are not well understood. This study of conservatively managed iAFF assessed factors influencing iAFF healing and progression including the effects of bisphosphonates and teriparatide use.

MATERIALS AND METHODS

Single-center retrospective observational study of 69 consecutive patients with 78 radiographically confirmed iAFF from 2002 to 2017. Serial radiographs assessed for focal cortical thickening, dreaded black line (DBL) and complete fracture. Chief outcome measures were DBL healing and complete fracture.

RESULTS

DBL had a significant association (p < 0.05) with fracture progression by multivariable logistic regression (55.8% versus 25.7%, odds ratio [OR] 26.57 (95% CI 1.40-504.78)) and shorter fracture-free survival (mean 3.21 versus 6.27 years). Presence of symptoms was associated with shorter fracture-free survival (mean 2.68 versus 5.98 years). Discontinuing bisphosphonates had significant associations (p < 0.001) by multivariable logistic regression with decreased fracture rate (11.6% versus 92.0%; OR 0.00, 95% CI 0.00-0.08) and longer fracture-free survival (mean 7.52 versus 1.99 years). DBL healing occurred in 36.4%, only when bisphosphonates were discontinued. Age, sex, race, fracture site, glucocorticoid use, teriparatide supplementation and duration of bisphosphonate use showed no statistically significant effect although teriparatide use appeared to improve DBL healing (50% versus 17.9%, p = 0.188).

CONCLUSIONS

In conservatively managed iAFF, DBL healing occurred in 36.4% if bisphosphonates were discontinued. Bisphosphonates and DBL were significantly associated with fracture progression and together with symptoms with fracture survival.

Surgical and Pharmacological Management of Periprosthetic Atypical Femoral Fractures: A Narrative Literature Review

Introduction

An increasing number of patients is annually undergoing total hip arthroplasty (THA), and a significant proportion of these patients are elderly and consequently at a higher risk of complications because of age, osteoporosis, and medical comorbidities. Periprosthetic femoral fractures (PFFs) are one of the worst complications of THA associated with high rates of unfavorable prognosis. Besides, in the last decade, a new independent disease entity called “atypical femoral fracture” (AFF) has been identified and defined by the American Society for Bone and Mineral Research (ASBMR) task force. Some PFFs present clinical history and radiographic aspect consistent with an AFF, meeting the ASBMR criteria for the diagnosis of AFF except that PFFs by themselves are an exclusion criterion for AFF. However, there is an increasing number of published studies suggesting that periprosthetic atypical femoral fractures (PAFFs) exist and should not be excluded by definition.

Significance

Nowadays, although there is an increasing interest in PAFFs, there are still very few studies published on the topic and a lack of consensus regarding their treatment. This narrative literature review aims to introduce this new emerging topic to a wider readership describing the characteristics of PAFFs and the state-of-the-art in their management.

Conclusions

Many authors agree that PAFFs should be considered as a subgroup of PFFs that have atypical characteristics; they also show a significant correlation with prolonged bisphosphonate use. A correct diagnosis is paramount for proper treatment of the disease that requires both surgical and medical actions to be taken.

The Effect of Teriparatide on the Hip: A Literature Review

Teriparatide (TPTD) is a bone-forming agent used to treat postmenopausal osteoporosis. Since hip fractures are related to higher morbidity and mortality rates than other fractures, efficacious osteoporosis drugs for the hip are critical. We reviewed research articles reporting the efficacy of TPTD in terms of bone mineral density (BMD), fractures prevention, changes in the outer diameter, cortical thickness and porosity, post-operative periprosthetic BMD loss, and healing of typical and atypical fractures of the hip. Data meta-analyses indicated that TPTD not only increased the BMD of the proximal femur but also decreased the risk of hip fractures. Even though TPTD increases the cortical bone porosity of the proximal femur, the bone strength does not decrease as the majority of the porosity is located at the endocortex; further, it increases the outer diameter and thickens the cortical bone. TPTD stimulates bone remodeling and facilitates callus maturity and fracture healing. There have been many reports on improving the effect of TPTD on the healing of atypical fractures; therefore it is advisable to use TPTD considering the increase benefit compared to the risk.

Is vitamin K2 a treatment choice for atypical femoral fractures in patients with secondary osteoporosis?

An atypical femoral fracture (AFF) is a rare complication associated with excessive inhibition of osteoclast expression during treatment of osteoporosis. We herein describe a patient who had been treated with alendronate for more than 10 years and subsequently developed an AFF that healed after treatment with vitamin K₂ (VK2). We also discuss the potential beneficial effects of VK2 on the healing of AFFs. A 48-year-old Asian man with secondary osteoporosis was treated with alendronate for more than 10 years. The patient underwent surgical treatment for a complete AFF of the right femur. Six months postoperatively, he complained of pain in his left thigh. X-ray examination revealed an incomplete AFF of the left femoral shaft. He was then treated with VK2. After 4 months of VK2 treatment, the patient reported that the pain in his left thigh had decreased, and follow-up X-ray examination demonstrated healing of the left AFF line. This case report indicates that VK2 may be a potential direction for pharmacological treatment of AFFs in future research.

Evaluation and management of atypical femoral fractures: an update of current knowledge

Atypical femoral fractures are often attributed to the use of anti-resorptive medications such as bisphosphonates (BP). Whilst they have proven effects on fragility fracture prevention, clinical and laboratory evidence is evolving linking BP-related suppression of bone remodelling to the development of atypical stress-related sub-trochanteric fractures (Shane et al. in JBMR 29:1-23, 2014; Odvina et al. in JCEM 90:1294-301, 2005; Durchschlag et al. in JBMR 21(10):1581-1590, 2006; Donnelly et al. in JBMR 27:672-678, 2012; Mashiba et al. in Bone 28(5):524-531, 2001; Dell et al. in JBMR 27(12):2544-2550, 2012; Black et al. in Lancet 348:1535-1541, 1996; Black et al. in NEJM 356:1809-1822, 2007; Black et al. in JAMA 296:2927-2938, 2006; Schwartz et al. in JBMR 25:976-82, 2010). Injuries may present asymptomatically or with prodromal thigh pain and most can be successfully managed with cephalomedullary nailing and discontinuation of BP therapy. Such injuries exhibit a prolonged time to fracture union with high rates of non-union and metal-work failure when compared to typical subtrochanteric osteoporotic femoral fractures. Despite emerging literature on AFFs, their management continues to pose a challenge to the orthopaedic and extended multi-disciplinary team. The purpose of this review includes evaluation of the current evidence supporting the management of AFFs, clinical and radiological features associated with their presentation and a review of reported surgical strategies to treat and prevent these devastating injures.

Intermittent Parathyroid Hormone Accelerates Stress Fracture Healing More Effectively Following Cessation of Bisphosphonate Treatment

Parathyroid hormone (PTH) and bisphosphonates (BPs), including alendronate (ALN), have opposing effects on bone dynamics. The extent to which PTH remains effective in the treatment of stress fracture (SFx) in the presence of an ongoing BP treatment has not been tested. SFx was induced in 150 female Wistar rats, divided into five equal groups (n = 30). All rats were pretreated with ALN (1 μg/kg^-1/day^-1) for 14 days prior to SFx induction, followed by ALN cessation or continuation for the duration of the experiment; this was combined with daily PTH (8 μg/100 g^-1/day^-1) on SFx induction for 14 days, followed by cessation or continuation of ALN after SFx induction or an equivalent vehicle as a control. Ulnas were examined 2 weeks or 6 weeks following SFx. Two toluidine blue- and two tartrate-resistant acid phosphatase-stained sections were examined for histomorphometric analysis using Osteomeasure software. There was a significant interaction between the effects of time and treatment type on the woven bone width and apposition rate, as well as an improvement in the woven bone architecture. However, woven bone variables remained unaffected by the cessation or continuation of ALN. Cessation of ALN increased osteoclast number when compared with the ALN-PTH continuation group (p = 0.006), and vehicle (p = 0.024) after 2 weeks. There was a significant interaction between the effects of time and treatment type on the number of osteoclasts per unit BMU area and length. The number of osteoclasts per unit BMU area and length was significantly greater in ALN cessation groups. It was concluded that intermittent short-duration iPTH treatment effectively increased remodeling of SFx with a concurrent BP treatment, provided that BP was ceased at the time of SFx. Our results could help develop shorter iPTH treatment protocols for the clinical management of SFxs and guide clinical decision-making to cease BP treatment in cases of SFx. © 2020 The Authors. JBMR Plus published by Wiley Periodicals LLC. on behalf of American Society for Bone and Mineral Research.

Short-Term Teriparatide for Bone Marrow Edema Secondary to Complex Regional Pain Syndrome: Case Reports on Efficacy After Two Years of Follow-Up

Bone marrow edema secondary to chronic pain syndrome after knee trauma is a disabling condition that presents with localized pain, allodynia, edema, decreased range of motion and osteopenia. The management includes a variety of medications and rehabilitation. The treatment of refractory diseases is challenging for most physicians. We present two cases of refractory bone edema secondary to complex regional pain syndrome that were successfully treated with a short-term regimen of teriparatide (TPT), a biosynthetic analogue (PTH 1-34) of the human parathormone. The rapid and sustained pain reduction with recovery of knee function for two years following administration of TPT demonstrated its potential for the treatment of bone edema due to complex regional pain syndrome.

Medical Management of Patients After Atypical Femur Fractures: a Systematic Review and Recommendations From the European Calcified Tissue Society

CONTEXT

Atypical femur fractures (AFFs) are serious adverse events associated with bisphosphonates and often show poor healing.

EVIDENCE ACQUISITION

We performed a systematic review to evaluate effects of teriparatide, raloxifene, and denosumab on healing and occurrence of AFF.

EVIDENCE SYNTHESIS

We retrieved 910 references and reviewed 67 papers, including 31 case reports, 9 retrospective and 3 prospective studies on teriparatide. There were no RCTs. We pooled data on fracture union (n = 98 AFFs on teriparatide) and found that radiological healing occurred within 6 months of teriparatide in 13 of 30 (43%) conservatively managed incomplete AFFs, 9 of 10 (90%) incomplete AFFs with surgical intervention, and 44 of 58 (75%) complete AFFs. In 9 of 30 (30%) nonoperated incomplete AFFs, no union was achieved after 12 months and 4 (13%) fractures became complete on teriparatide. Eight patients had new AFFs during or after teriparatide. AFF on denosumab was reported in 22 patients, including 11 patients treated for bone metastases and 8 without bisphosphonate exposure. Denosumab after AFF was associated with recurrent incomplete AFFs in 1 patient and 2 patients of contralateral complete AFF. Eight patients had used raloxifene before AFF occurred, including 1 bisphosphonate-naïve patient.

CONCLUSIONS

There is no evidence-based indication in patients with AFF for teriparatide apart from reducing the risk of typical fragility fractures, although observational data suggest that teriparatide might result in faster healing of surgically treated AFFs. Awaiting further evidence, we formulate recommendations for treatment after an AFF based on expert opinion.

Natural history of incomplete atypical femoral fractures in patients after a prolonged and variable course of bisphosphonate therapy-a long-term radiological follow-up

Understanding the natural history of lateral femoral stress fractures helps to guide their management. Improvement in their radiographic characteristics is rare. Progression was generally sequential, most developing an incomplete fracture line before fracture displacement. Stopping bisphosphonates decreased the fracture rate, a feasible management option for lesions without incomplete fracture lines.

INTRODUCTION

Retrospective study evaluating the natural history of lateral femoral stress fractures (FSF) by serial radiography over a variable period of time in a cohort of patients treated for some time with bisphosphonates for osteoporosis, whilst also identifying the fracture response in cases where bisphosphonates were discontinued.

METHODS

The radiographs of 76 consecutive patients (92 femurs) with 161 FSF were reviewed to document their change over time. Femurs were classified into the following: A-normal, B-focal cortical thickening, C-dreaded black line and D-displaced fracture. Bisphosphonate history was recorded.

RESULTS

66.5% FSF showed group stability between the first and last radiographs: group B (79.1%), group C (45.7%). 28.6% progressed, mostly following an ordered sequence starting from group A, progressing to B, then C, before culminating in D. Progression rate was as follows: A-100% (11/11), B-18.3% (21/115), C-40% (14/35). Regression in FSF was uncommon-5.6% (8/161). 34.8% (32/92) sustained displaced fractures. Kaplan-Meier analysis showed statistically significant difference between the groups; median survival (95% CI): A-4189 (-), B-3383.0 (-), C-1807 (0.0-3788.6) and progression to displaced fracture when bisphosphonate had been stopped for at least 6 months. The group without recent bisphosphonates had a lower group progression rate (17.1%, 12/70). Nevertheless, 10.9% (5/46) progressed to displaced fracture. This group also had the highest proportion of stable (77.1%, 54/70) and regressive lesions (5.7%, 4/70).

CONCLUSIONS

In FSF, there is natural progression from normal bone, to focal cortical thickening, to dreaded black line and eventually to displaced fracture. Most lesions persist, remaining static or progressing, especially if a dreaded black line is present and bisphosphonates are continued. Regression is uncommon and more frequent when bisphosphonates are discontinued. Despite stopping bisphosphonates, there remains a 10.9% risk of progression to displaced fracture.

Atypical Femur Fractures: Review of Epidemiology, Relationship to Bisphosphonates, Prevention, and Clinical Management

Bisphosphonates (BPs) are highly effective in treating osteoporosis and reducing hip, vertebral, and other fractures by as much as 50% to 70%. However, since 2006, atypical femur fractures (AFFs) emerged as potential side effects of BPs and other treatments. These fractures have unusual radiologic features and occur with little trauma. Public concern has led to a >50% decrease in BP usage. AFFs are rare: for each AFF, >1200 fractures, including 135 hip fractures, are prevented. Case definition criteria were updated by the American Society of Bone and Mineral Research in 2014. Many epidemiologic studies have been reported, and although methodologically challenging, generally support a BP-AFF association. However, the magnitude of the association between BPs and AFFs is uncertain: estimates of relative risk for AFFs among BP users vs nonusers range from 1 to 65 with a meta-analysis estimate of 1.7. Although mechanistic studies have proposed several hypotheses explaining how BPs might decrease bone strength, AFF pathogenesis remains uncertain and cannot explain the paradox of efficacy of reduction of common fractures while increasing risk for rare fractures at one site. There are several consistent risk factors, including Asian race (in North America), femoral bowing, and glucocorticoid use, whereas others remain unclear. Consensus is emerging about strategies to prevent AFFs in BP users (including drug holidays after 5 years' use in some patients). In conclusion, AFFs can be devastating, but even under the most pessimistic assumptions, the benefit/risk ratio is highly positive for BPs, particularly during 3 to 5 years of use. As understanding of AFFs increases, it is becoming increasingly possible to maximize BP benefits while minimizing AFF risk.

Surgical Management of Atypical Femur Fractures Associated With Bisphosphonate Therapy

Atypical femur fractures associated with long-term bisphosphonate use can be challenging injuries to manage. Not only do they have a prolonged healing time and increased rate of nonunion as compared to typical femur fractures, intraoperative complications are not infrequent and can be catastrophic. Given the pathologic nature of these fractures, a multidisciplinary approach to the patient's care is necessary. Treatment begins with medical optimization and careful surgical planning. Radiographic characteristics of the fracture and femoral osteology dictate reduction strategy, adjunctive surgical techniques, and implant choice. Intraoperative complications including malreduction, iatrogenic fracture, and fracture propagation can be avoided with thoughtful planning. The purpose of this article is to discuss the technical aspects of surgical management of atypical femur fractures. We also discuss management of intraoperative complications and treatment failure. Finally, we provide an update on recommendations for postoperative medical treatment and management of the contralateral femur.

The effects of teriparatide on acceleration of bone healing following atypical femoral fracture: comparison between daily and weekly administration

We compared the effectiveness of promoting bone healing between two teriparatide preparations for atypical femoral fracture (AFF). A total of 45 AFFs were included in this study, and we compared the duration of bone union. Teriparatide administered by daily injection enhanced bone union more than weekly administration in complete AFFs.

INTRODUCTION

The efficacy of teriparatide for atypical femoral fracture (AFF) has been recently reported. Although two different teriparatide preparations can be used to treat osteoporosis in Japan, daily or weekly injection, all previous reports on the effectiveness of teriparatide for AFF only examined daily injection formulations. Therefore, we compared the promotion of bone healing between the two teriparatide preparations for AFF.

METHODS

A total of 45 consecutive AFFs in 43 Japanese patients were included in this study. They received either a daily 20-μg teriparatide injection (daily group; n = 32) or a once-a-week 56.5-μg teriparatide injection (weekly group; n = 13). We compared the clinical background and duration of bone union between these two groups.

RESULTS

When all patents were included, the fracture healing time was not significantly different between the two groups. Only patients with complete AFFs had significantly fewer daily bisphosphonate or denosumab injections than the weekly group (P < 0.05). The fracture healing time in the daily group (6.1 ± 4.1 months) was significantly shorter than that in the weekly group (10.1 ± 4.2 months) (P < 0.05). Even if the influence of bisphosphonate or denosumab usage was excluded, a similar significant difference was observed in the fracture healing time (P < 0.05). There was no significant difference between the two groups among patients with incomplete AFFs.

CONCLUSIONS

Daily teriparatide injections enhance bone union more than weekly injections in complete AFF patients.

Subtrochanteric and diaphyseal femoral fractures in hypophosphatasia-not atypical at all

Risk for subtrochanteric and diaphyseal femoral fractures is considered increased in patients with hypophosphatasia (HPP). Evaluating a large cohort of HPP patients, we could for the first time quantify the prevalcence and identify both morphometric features as well as predisposing factors for this complication of severe HPP.

INTRODUCTION

Subtrochanteric and diaphyseal femoral fractures have been associated with both, long-term antiresorptive treatment and metabolic bone disorders, specifically Hypophosphatasia (HPP). Building on a cross-sectional evaluation of real-world data, this study reports risk factors, prevalence, treatment outcome and morphometric particularities for such fractures in HPP as compared to Atypical Femoral Fractures (AFF) in long-term antiresorptive treatment.

METHODS

For 15 out of 150 HPP patients identified with having experienced at least one such fracture, medical records were reviewed in detail, extracting medical history, genotype, lab assessments, bone mineral density (DXA), radiographic data on femoral geometry and clinical aspects of fracture etiology and healing.

RESULTS

Bilateral fractures were documented in 10 of these 15 patients, yielding a total of 25 fractures for evaluation. Disease-inherent risk factors included autosomal-recessive, childhood onset HPP, apparently low alkaline phosphatase (ALP) ≤ 20 U/l and substantially elevated pyridoxal 5'-phosphate (PLP) > 3 times upper limit of normal as well as high lumbar spine BMD. Fracture morphology met definition criteria for AFF in 88% of cases. Femoral geometry revealed additional risk factors previously described for AFF, including decreased femoral neck-shaft angle and increased femoral offset. Extrinsic risk factors include Hypovitaminosis D (80%) and pre-treatment with bisphosphonates (46,7%) and Proton-Pump Inhibitors (40%).

CONCLUSIONS

Increased risk for subtrochanteric and diaphyseal femoral fractures in HPP appears to result from both compromised bone metabolism as well as disease-associated bone deformities. In severe HPP, generous screening for such fractures seems advisable. Bisphosphonates and Hypovitaminosis D should be avoided. Healing is compromised and requires mindful consideration of both pharmacological and surgical options.

A proposal for an atypical femur fracture treatment and prevention clinical practice guideline

The prevention as well as the treatment of atypical femur fractures (AFFs) remains controversial but there have been many clinical recommendations suggested. We have summarized these recommendations as well as expanded upon them in this paper.

INTRODUCTION

The purpose of the paper was to develop a clinical practice guideline that both treats AFF and decreases the risk of AFF in patients requiring antiresorptive medications. Examples of these medications include bisphosphonates and denosumab for the treatment of osteoporosis.

METHODS

A literature review looking for recommendations on AFF identification, management, and prevention was done. We also performed an updated review of clinical guidelines on AFF prevention and treatment that were developed for the Kaiser Permanente osteoporosis/fracture prevention team.

RESULTS

Concise clinical practice guidelines are presented that can be applied in treatment of AFF as well as help reduce the risk of developing an AFF in patients requiring antiresorptive medications. These guidelines are based on using both typical fracture and AFF risk assessment to determine duration of antiresorptive of 3 to 5 years before consideration if a drug holiday is needed. Specific groups such as younger Asian women should be reassessed at 3 years with DXA and FRAX to see if a drug holiday is needed whereas patients at higher risk for typical fractures may be reassessed at 5 years of treatment. The DXA rescreening can now be accessed if focal or generalized lateral cortex changes are present that may indicate incomplete AFFs are present. If an incomplete AFF is discovered either by DXA or by other imaging studies, it is imperative to stop antiresorptive medications and to take additional measures to lower the risk of progression to a complete AFF. If complete AFF does occur, then antiresorptive medications should be stopped and additional measures should be taken to decrease the risk of developing an AFF on the contralateral femur.

CONCLUSIONS

Clinical practice guidelines for the treatment and prevention of AFF will benefit clinicians who are frequently faced with having to make clinical decisions in patients requiring antiresorptive medications.

Anabolic agents: what is beyond osteoporosis?

Osteoporosis is a common skeletal disorder characterized by low bone mass, which leads to reduced bone strength and an increased risk of fractures. Anabolic agents have been shown to improve bone mass and decrease fracture risk in osteoporosis patients by directly stimulating osteoblasts to produce new bone. Currently, two anabolic agents are available in the USA: recombinantly produced teriparatide (TPTD), which is the fully active (1-34) amino active sequence of human parathyroid hormone (PTH), and abaloparatide (APTD), a synthetic analog of parathyroid hormone-related peptide (PTHrP). At present, both agents are approved only for treatment of patients with osteoporosis at high risk of fracture. Nonetheless, their anabolic properties have led to off-label application in additional settings which include spine fusion, osteonecrosis of the jaw, arthroplasty, and fracture healing. In this article, we summarize available scientific literature regarding the efficacy, effectiveness, and safety of TPTD in these off-label settings.

Atypical fractures: An issue of concern or a myth?

Atypical Femoral Fractures (AFF) represent fractures located between the lesser trochanter and the supracondylar flare of a femur. An increasing pool of evidence supports their association with the prolonged use of bisphosphonates, even though a direct correlation is yet to be proved. The purpose of this review is to encapsulate the current evidence associating bisphosphonate use and the development of AFFs, the clinical features related to their presentation, as well as to report the armamentarium of strategies available in the prevention and treatment of AFFs. Based on these evidence, we propose a management algorithm for AFFs, that can serve as a guide for patients presenting with this condition.

A review of atypical subtrochanteric femoral fractures in Northern Ireland between 2010 and 2014

The term atypical femoral fractures most commonly occur in the subtrochanteric area. Concerns exist regarding the role of bisphosphonate treatment in their aetiology. Which surgical intervention provides the best outcome remains contentious. We reviewed all atypical subtrochanteric femoral fractures treated in Northern Ireland over 5 years, specifically investigating incidence, prodromal symptoms, association with bisphosphonates and optimal fixation methods. All subtrochanteric fractures treated in the region were identified and reviewed for atypical features. Case notes and imaging were then reviewed for each patient. A total of 364 subtrochanteric femoral fractures were identified during the 5-year study period. Twenty-six of these met the criteria for an atypical fracture (7%). Thirteen patients (50%) had presented with prodromal symptoms prior to complete fracture, six of which had radiological evidence of an incomplete fracture of the lateral cortex. Thirteen patients had a history of bisphosphonate treatment. All were treated operatively, with twenty-five cephalomedullary nails and one dynamic hip screw. Twenty-one patients had follow-up for greater than 2 months, nine of which (42.9%) achieved radiological union with a mean time to union of 297 days. Dynamically locked nails had a higher union rate than statically locked (80% versus 33.3%). Four patients required major revision surgery (15.4%). The quality of reduction was statistically significant in predicting need for revision. Atypical fractures often present with prodromal symptoms. Complete fractures are difficult to successfully manage with longer than expected times to union. Treatment with a dynamically locked, cephalomedullary with a good reduction provided the best results.

Surgical outcome of atypical subtrochanteric and femoral fracture related to bisphosphonates use in osteoporotic patients with or without teriparatide treatment

Background

Atypical subtrochanteric fracture and femoral fracture have been considered to be rare complications related to long-term bisphosphonates use. A reduced bone turnover rate may lead to delayed bone healing. Limited data have revealed that teriparatide treatment may reverse the effect of bisphosphonates and be effective in bone healing.

Methods

We reviewed patients with atypical subtrochanteric and femoral fracture related to bisphosphonates use between January 2008 and December 2014. Thirteen female patients were enrolled. Radiographic findings were compatible with the characteristics of atypical fracture. Surgical intervention was performed for all, and teriparatide use was advised postoperatively. Outcome measures included perioperative results, and clinical and radiographic outcome.

Results

Of the 13 female patients enrolled, 10 had subtrochanteric and 6 had proximal femoral fracture; 3 had bilateral fractures. The mean age of the patients at surgery was 70.15±6.36 years. Most fractures (68.8%) presented prodromal thigh pain. All patients were treated with an intramedullary fixation system without severe complications. The patients were divided into 2 groups based on whether they had received treatment with teriparatide or not. The mean time to bone union was 4.4 months in the teriparatide-treated group, and 6.2 months in the non-teriparatide-treated group (p=0.116). Six patients (75%) in the teriparatide-treated group and 4 (50%) in the non-teriparatide-treated group (p= 0.3) achieved bone union within 6 months. The means of the modified Harris Hip Score and Numerical Rating Scale were significantly better in the teriparatide-treated group at postoperative 6 months. Seven patients had the same ability to walk at the 1-year follow-up as they did before the atypical fracture.

Conclusions

Teriparatide treatment in patients with atypical fracture may help in fracture healing, hip function recovery, and pain relief in this reduced bone turnover patient group.

Short-term daily teriparatide in patients with rheumatoid arthritis

OBJECTIVE

The aim of this study was to compare the efficacy of six-month teriparatide treatment followed by six-month bisphosphonate therapy with 12-month bisphosphonate monotherapy in Japanese rheumatoid arthritis (RA) patients who had not been previously treated for osteoporosis.

METHODS

A total of 34 RA patients with osteoporosis were enrolled. Thirteen patients received six-month teriparatide prior to six-month minodronate therapy (PTH group), and 21 patients received 12-month minodronate therapy (BP group). Bone mineral density (BMD), and bone turnover markers were measured prior to and 6 and 12 months after the initiation of treatment.

RESULTS

Bone mineral density of the spine was significantly increased after 12 months of treatment in both groups. In the PTH group, the mean percent change of BMD of the spine was significantly higher at 12 months after the initiation of treatment, as compared to the BP group (PTH group: 9.9 ± 1.5%, BP group: 5.5 ± 0.7%). Femoral neck BMD was significantly increased only in the PTH group after 12 months.

CONCLUSION

Therapy involving six-month teriparatide followed by six-month minodronate therapy increased spine BMD to a greater degree than 12-month minodronate monotherapy. The strategy of short-term administration of teriparatide for RA patients with osteoporosis might be useful when additional bisphosphonate therapy is considered.

Atraumatic segmental atypical femur fracture secondary to bisphosphonate use: A case report

Atypical femur fractures as a result of long term bisphosphonate use are characterized by several unique radiographic features. We describe an atypical femur fracture treated by cephalomedullary nail with a previously undescribed segmental fracture pattern. Other than 1.5 years of bisphosphonate use the patient did not have any other risk factors known to cause atypical femur fractures. Judicious bisphosphonate use as well as increased awareness of the associated complications may help reduce the rate of bisphosphonate associated atypical femur fractures.

Intramedullary Nail Fixation of Atypical Femur Fractures With Bone Marrow Aspirate Concentrate Leads to Faster Union: A Case-Control Study

OBJECTIVES

To evaluate bone marrow aspirate concentrate (BMAC) use in the treatment of AFF.

DESIGN

Retrospective case control.

SETTING

Level 1 trauma center.

PATIENTS

Complete AFF, defined according to American Society of Bone and Mineral Research (ASBMR) criteria, from September 2009 to April 2015 with minimum 1-year follow-up.

INTERVENTION

Operative treatment with antegrade intramedullary nails. Beginning June 2014, BMAC from the ipsilateral iliac crest was added to all AFFs.

MAIN OUTCOME MEASUREMENTS

Time to union as determined by a blinded panel of 3 attending orthopaedic surgeons, union rates, complications.

RESULTS

Thirty-five patients with 36 AFFs were reviewed, of which 33 AFFs were included and 11 received BMAC. Alendronate was the most commonly prescribed bisphosphonate, with a similar mean duration of use in controls and BMAC cases (5.6 versus 6 years, P = 0.79). BMAC use significantly decreased time to union (3.5 versus 6.8 months, P = 0.004). Varus malreduction was associated with a significant delay in union (9.7 versus 4.7 months, P = 0.04). Overall, 1 year union rate was 86.2% and nonsignificantly higher in BMAC compared with controls (100.0% versus 77.3%, P = 0.11). Multivariate analysis revealed BMAC and varus malreduction as independent predictors of time to union. There were no complications related to BMAC use.

CONCLUSION

Our findings support intramedullary nailing of AFFs as an effective treatment option with a low surgical complication rate and highlight the importance of avoiding varus malreduction. BMAC use significantly reduced time to fracture union without an increase in surgical complication rates.

LEVEL OF EVIDENCE

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

Atypical femoral fractures related to bisphosphonate treatment: issues and controversies related to their surgical management

AIMS

Treatment guidelines for atypical femoral fractures associated with bisphosphonates have not been established. We conducted a systematic review of the treatment of atypical femoral fractures first, to evaluate the outcomes of surgical fixation of complete atypical fractures and secondly, to assess whether prophylactic surgery is necessary for incomplete atypical fractures.

MATERIALS AND METHODS

Case reports and series were identified from the PubMed database and were included if they described the treatment of atypical femoral fractures. In total, 77 publications met our inclusion criteria and 733 patients with 834 atypical complete or incomplete femoral fractures were identified.

RESULTS

For complete fractures, internal fixation was predominantly achieved by intramedullary nailing. The mean time to healing post-operatively was 7.3 months (2 to 31). Revision surgery for nonunion or implant failure was needed in 77 fractures (12.6%). A greater percentage of fractures treated with plate fixation (31.3%) required revision surgery than those treated with intramedullary nailing (12.9%) (p < 0.01). Non-operative treatment of incomplete fractures failed and surgery was eventually needed in nearly half of the patients (47%), whereas prophylactic surgery was successful and achieved a 97% rate of healing.

CONCLUSION

Intramedullary nailing is the first-line treatment for a complete fracture, although the risk of delayed healing and revision surgery seems to be higher than with a typical femoral fracture. Non-operative treatment does not appear to be a reliable way of treating an incomplete fracture: prophylactic intramedullary nailing should be considered if the patient is in intractable pain. Radiographs of the opposite side should be obtained routinely looking for an asymptomatic fracture. Bisphosphonates must be discontinued but ongoing metabolic management in the form of calcium and/or vitamin D supplements is advisable. Teriparatide therapy can be considered as an alternative treatment. Cite this article: Bone Joint J 2017;99-B:295-302.

Bisphosphonates and atypical subtrochanteric fractures of the femur

OBJECTIVES

Bisphosphonates are widely used as first-line treatment for primary and secondary prevention of fragility fractures. Whilst they have proved effective in this role, there is growing concern over their long-term use, with much evidence linking bisphosphonate-related suppression of bone remodelling to an increased risk of atypical subtrochanteric fractures of the femur (AFFs). The objective of this article is to review this evidence, while presenting the current available strategies for the management of AFFs.

METHODS

We present an evaluation of current literature relating to the pathogenesis and treatment of AFFs in the context of bisphosphonate use.

RESULTS

Six broad themes relating to the pathogenesis and management of bisphosphonate-related AFFs are presented. The key themes in fracture pathogenesis are: bone microdamage accumulation; altered bone mineralisation and altered collagen formation. The key themes in fracture management are: medical therapy and surgical therapy. In addition, primary prevention strategies for AFFs are discussed.

CONCLUSIONS

This article presents current knowledge about the relationship between bisphosphonates and the development of AFFs, and highlights key areas for future research. In particular, studies aimed at identifying at-risk subpopulations and organising surveillance for those on long-term therapy will be crucial in both increasing our understanding of the condition, and improving population outcomes.Cite this article: N. Kharwadkar, B. Mayne, J. E. Lawrence, V. Khanduja. Bisphosphonates and atypical subtrochanteric fractures of the femur. Bone Joint Res 2017;6:144-153. DOI: 10.1302/2046-3758.63.BJR-2016-0125.R1.

A new contralateral atypical femoral fracture despite sequential therapy with teriparatide and strontium ranelate

Atypical femoral fractures (AFFs) are a rare association of anti-resorptive therapy for osteoporosis. Limited evidence-based management guidelines on their optimal treatment exist, with observational studies suggesting a role for teriparatide (TPTD) in AFF healing. We report a case of a 65-year-old woman with postmenopausal osteoporosis who sustained an AFF following long-term bisphosphonate therapy, and who subsequently developed a new contralateral AFF after completion of TPTD therapy and initiation of strontium ranelate (SR) treatment. The sequence of events in this case report showed that TPTD and SR did not prevent the development of a new AFF, and questions the optimal treatment of these stress fractures.

•

A patient sustained a bisphosphonate-associated atypical femoral fracture (AFF).

•

A contralateral AFF occurred despite sequential therapy with teriparatide and strontium ranelate.

•

The role of teriparatide in the treatment of AFF remains uncertain.

•

The use of strontium ranelate following an AFF is cautioned.

Thai Osteoporosis Foundation (TOPF) position statements on management of osteoporosis

The adjusted incidence rate of hip fracture in Thailand has increased more than 31% from 1997 to 2006. Mortality and morbidity after hip fracture are also high. One year mortality after a hip fracture has increased from 18% in 1999 to 21% in 2007. The Thai Osteoporosis Foundation (TOPF) developed the first Clinical Practice Guideline (CPG) in 2002 and keeps updating the CPG since then. This latest version of the CPG is our attempt to provide comprehensive positional statement on the diagnosis, prevention and treatment of osteoporosis in Thailand. The study group who revised this position statement contains experts from the TOPF, Four Royal Colleges of Thailand, includes the Orthopaedic Surgeons, Gynecologists and Obstetricians, Physiatrists, Radiologists and 2 Associations of Endocrinologists and Rheumatologists which have involved in the management of patients with osteoporosis.

Athletic Population with Spondylolysis: Review of Outcomes following Surgical Repair or Conservative Management

STUDY DESIGN

Narrative review.

OBJECTIVE

The study aims to critically review the outcomes associated with the surgical repair or conservative management of spondylolysis in athletes.

METHODS

The English literature listed in MEDLINE/PubMed was reviewed to identify related articles using the term "spondylolysis AND athlete." The criteria for studies to be included were management of spondylolysis in athletes, English text, and no year, follow-up, or study design restrictions. The references of the retrieved articles were also evaluated. The primary outcome was time to return to sport. This search yielded 180 citations, and 25 publications were included in the review.

RESULTS

Treatment methods were dichotomized as operative and nonoperative. In the nonoperative group, 390 athletes were included. A combination of bracing with physical therapy and restriction of activities was used. Conservative measures allowed athletes to return to sport in 3.7 months (weighted mean). One hundred seventy-four patients were treated surgically. The most common technique was Buck's, using a compression screw (91/174). All authors reported satisfactory outcomes. Time to return to play was 7.9 months (weighted mean). There were insufficient studies with suitably homogenous subgroups to conduct a meta-analysis.

CONCLUSION

There is no gold standard approach for the management of spondylolysis in the athletic population. The existing literature suggests initial therapy should be a course of conservative management with thoracolumbosacral orthosis brace, physiotherapy, and activity modification. If conservative management fails, surgical intervention should be considered. Two-sided clinical studies are needed to determine an optimal pathway for the management of athletes with spondylolysis.

The role of peptides in bone healing and regeneration: a systematic review

BACKGROUND

Bone tissue engineering and the research surrounding peptides has expanded significantly over the last few decades. Several peptides have been shown to support and stimulate the bone healing response and have been proposed as therapeutic vehicles for clinical use. The aim of this comprehensive review is to present the clinical and experimental studies analysing the potential role of peptides for bone healing and bone regeneration.

METHODS

A systematic review according to PRISMA guidelines was conducted. Articles presenting peptides capable of exerting an upregulatory effect on osteoprogenitor cells and bone healing were included in the study.

RESULTS

Based on the available literature, a significant amount of experimental in vitro and in vivo evidence exists. Several peptides were found to upregulate the bone healing response in experimental models and could act as potential candidates for future clinical applications. However, from the available peptides that reached the level of clinical trials, the presented results are limited.

CONCLUSION

Further research is desirable to shed more light into the processes governing the osteoprogenitor cellular responses. With further advances in the field of biomimetic materials and scaffolds, new treatment modalities for bone repair will emerge.

Short-term effects of teriparatide versus placebo on bone biomarkers, structure, and fracture healing in women with lower-extremity stress fractures: A pilot study

AIMS

In this pilot, placebo-controlled study, we evaluated whether brief administration of teriparatide (TPTD) in premenopausal women with lower-extremity stress fractures would increase markers of bone formation in advance of bone resorption, improve bone structure, and hasten fracture healing according to magnetic resonance imaging (MRI).

METHODS

Premenopausal women with acute lower-extremity stress fractures were randomized to injection of TPTD 20-µg subcutaneous (s.c.) (n = 6) or placebo s.c. (n = 7) for 8 weeks. Biomarkers for bone formation N-terminal propeptide of type I procollagen (P1NP) and osteocalcin (OC) and resorption collagen type-1 cross-linked C-telopeptide (CTX) and collagen type 1 cross-linked N-telopeptide (NTX) were measured at baseline, 4 and 8 weeks. The area between the percent change of P1NP and CTX over study duration is defined as the anabolic window. To assess structural changes, peripheral quantitative computed topography (pQCT) was measured at baseline, 8 and 12 weeks at the unaffected tibia and distal radius. The MRI of the affected bone assessed stress fracture healing at baseline and 8 weeks.

RESULTS

After 8 weeks of treatment, bone biomarkers P1NP and OC increased more in the TPTD- versus placebo-treated group (both p ≤ 0.01), resulting in a marked anabolic window (p ≤ 0.05). Results from pQCT demonstrated that TPTD-treated women showed a larger cortical area and thickness compared to placebo at the weight bearing tibial site, while placebo-treated women had a greater total tibia and cortical density. No changes at the radial sites were observed between groups. According to MRI, 83.3% of the TPTD- and 57.1% of the placebo-treated group had improved or healed stress fractures (p = 0.18).

CONCLUSIONS

In this randomized, pilot study, brief administration of TPTD showed anabolic effects that TPTD may help hasten fracture healing in premenopausal women with lower-extremity stress fractures. Larger prospective studies are warranted to determine the effects of TPTD treatment on stress fracture healing in premenopausal women.

Management of atypical femoral fracture: a scoping review and comprehensive algorithm

BACKGROUND

Atypical femoral fractures (AFF) are a rare type of femoral stress fracture recently described, potentially associated with prolonged bisphosphonate therapy. Evidence-based recommendations regarding diagnosis and management of these fractures are scarce. The purpose of this study is to propose an algorithm for the diagnosis and management of AFF.

METHODS

We performed a PubMed search of the last ten years using the keywords "atypical femoral fractures" and identified further articles through an evaluation of the publications cited in these articles. Relevant studies were included by agreement between researchers, depending on their specialization. Pertinent points of debate were discussed based on the available literature, allowing for consensus regarding the proposed management algorithm.

RESULTS

Using a systematic approach we performed a scoping review that included a total of 137 articles.

CONCLUSIONS

A practical guide for diagnosis and management of AFF based on the current concepts is proposed. In spite of the impressive large volume of published literature available since AFF were initially identified, the level of evidence is mostly poor, in particular regarding treatment choice. Therefore, further studies are required.

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.

Periprosthetic Femoral Stress Fracture After Bisphosphonate Treatment Resulting in Nonunion Successfully Treated with Teriparatide: A Case Report

CASE

We present the case of a postmenopausal osteoporotic woman, treated with bisphosphonates, who developed a stress fracture at the tip of a revision femoral component, resulting in nonunion after several operative treatment attempts. The nonunion healed after 7 months of subcutaneous injections of 20 μg/day of teriparatide.

CONCLUSION

Teriparatide treatment should be considered for use in recalcitrant stress fractures after total hip arthroplasty.

Atypical femoral fracture post total hip replacement in a patient with hip osteoarthritis and an ipsilateral cortical thickening

INTRODUCTION

Atypical femoral fractures (AFF) can be present in patients with hip osteoarthritis (OA). This case highlights the opportunity to review the management of stress reactions, stress fractures and atypical femoral fractures, which depend on the activity of the fracture.

CASE PRESENTATION

A 66-year-old female with a history of long-term bisphosphonate use underwent a total hip replacement for symptomatic osteoarthritis with a clinical presentation of right groin pain and radiographic signs of joint space narrowing and osteophyte formation. Radiographs before hip arthroplasty showed lateral cortical thickening in the ipsilateral femur in the subtrochanteric region. The patient developed a complete periprosthesic atypical femoral fracture a month after surgery at the level of the previously identified femoral cortical thickening.

DISCUSSION

Given the high amount of elderly, osteoporotic patients presenting with groin/thigh pain undergoing hip replacement, surgeons should question them about the use of bisphosphonates in the past and look for the presence of AFF. These should receive bilateral imaging studies and a metabolic bone workup in order to define the status of the fracture and determine the appropriate management before considering any other surgical intervention.

Successful treatment of osteonecrosis-induced fractured mandible with teriparatide therapy: A case report

INTRODUCTION

The management of medication-related osteonecrosis of the jaw (MRONJ) is controversial. To date, there is no established treatment for cases of advanced stage 3 MRONJ osteoporosis in elderly patients.

PRESENTATION

An 87-year-old osteoporotic woman with osteonecrosis-induced left mandible fracture related to minodronate therapy was referred to us for treatment. She had a vertebral compression fracture concurrently and had started subcutaneous injection of teriparatide. After 18 months of treatment with teriparatide the pathological mandible fracture was healed and functional recovery of the occlusion was obtained by complete dentures.

DISCUSSION

Teriparatide may have a powerful anabolic effect on bone, and promote bone regeneration against pathologic mandible fracture induced by MRONJ.

CONCLUSION

Based upon these findings, teriparatide might be beneficial for advanced stage 3 MRONJ osteoporosis in elderly patients.

Applying low-intensity pulsed ultrasounds (LIPUS) to a zoledronate-associated atypical femoral shaft fracture without cessation of zoledronate therapy for 3 years follow up: a case report

Reports are increasing regarding atypical femoral fractures (AFFs) caused by minor trauma in patients using bisphosphonates (BPs) for long periods. Patients with malignant skeletal metastases potentially are at greater risk for these AFFs, especially considering the high dose and the duration of treatment with BPs. We evaluated a case of atypical femoral shaft fracture treated with an intramedullary nail in a patient treated for five years with zoledronate who had breast cancer with metastases to bone. Although bone union was achieved without cessation of zoledronate therapy by applying low-intensity pulsed ultrasounds (LIPUS), the remodeling phase of the fracture healing process was delayed. For BPs-associated AFFs, LIPUS is an alternative to parathyroid hormone (PTH) analogs such as teriparatide that are contraindicated in patients with malignant skeletal metastases. LIPUS is an effective treatment for fracture healing and may avoid the necessity to discontinue BP therapy.

Bilateral atypical femoral subtrochanteric fractures in a premenopausal patient receiving prolonged bisphosphonate therapy: evidence of severely suppressed bone turnover

We report a case of bilateral atypical femoral fractures that occurred in a patient who had been taking bisphosphonate long-term. A 36-year-old premenopausal female diagnosed with systemic lupus erythematosus and dermatomyositis had been treated with glucocorticoid and alendronate (5 mg/day) to prevent glucocorticoid-induced osteoporosis. She was taken to our hospital because she could not walk immediately after falling down from the standing position. A plain radiograph showed a subtrochanteric fracture of the left femur. Four months later, she fell again and sustained a contralateral subtrochanteric fracture. For each fracture, a femoral intramedullary nail was inserted. Delayed union was detected in both sides, and revision surgery with an iliac bone graft was required for implant breakage in the right side. Histomorphometric findings for the ilium revealed remarkably decreased osteoid volume with no osteoclasts and a minimally eroded surface, suggesting that bone turnover was severely suppressed. However, histology of the delayed union site revealed callus formation and some osteoclast appearance, suggesting that fracture healing was occurring. In total, it took 29 months (left) and 24 months (right) until fracture healing was achieved, showing delayed union. This case is extremely rare in that patient who presented with atypical femoral fractures in spite of her premenopausal status. The bone histomorphometric findings from this case suggest that severely suppressed bone turnover is associated with atypical femoral subtrochanteric fracture and can cause delayed union in patients treated with alendronate long-term.

Effect of Teriparatide on Healing of Atypical Femoral Fractures: A Systemic Review

BACKGROUND

Bisphosphonates (BPs) are the most commonly used anti-osteoporotic drugs, which have been proven to reduce the risk of osteoporotic fractures. However, use of BPs, particularly for long periods of time, is associated with an increased risk of atypical femoral fracture (AFF). Healing of BP-associated AFF is usually delayed because of suppressed bone turnover. Teriparatide (TPTD), a recombinant form of parathyroid hormone (PTH), enhances bone healing in patients with delayed healing or non-union.

METHODS

In this study, we summarized and performed a systemic review of the published literature on treatment of AFF using TPTD.

RESULTS

Although there is a lack of level 1 studies on the evidence of TPTD in promoting bone union in AFFs, this systemic review of the available literature revealed that TPTD works positively in AFFs, and we put together the evidence that TPTD is a viable treatment option for enhancing fracture healing in AFFs.

CONCLUSIONS

While anecdotal evidence of beneficial effects of TPTD on fracture healing offer limited guidance for clinical decision making, a better understanding of the role of TPTD in fracture healing may be elucidated with future prospective trials.

Healing of bisphosphonate-associated atypical femoral fractures in patients with osteoporosis: a comparison between treatment with and without teriparatide

Atypical femoral fracture (AFF) often appears with bisphosphonate use. Teriparatide (TPTD) treatment may promote AFF healing, but few controlled or comparative studies have examined the effects of TPTD on healing of bisphosphonate-associated AFF. We retrospectively reviewed the medical records of 45 consecutive AFFs in 34 Japanese patients who had received oral bisphosphonates (alendronate or risedronate) for osteoporosis before AFF and had been followed for ≥12 months (range, 12-90 months). Thirty-seven complete or incomplete AFFs (82 %) were treated surgically and eight incomplete AFFs (18 %) were treated conservatively. Bisphosphonates were stopped at diagnosis. Based on TPTD use after fracture, AFFs were divided into non-TPTD (n = 24) and TPTD (n = 21) groups. Time to fracture-healing and frequency of delayed healing or non-union were compared between groups. Because fracture type (complete or incomplete) differed significantly between groups, only subanalyses for all surgically treated AFFs (complete and incomplete), surgically treated complete AFFs, and conservatively treated incomplete AFFs were performed. In subanalyses for all AFFs treated surgically, mean (± standard deviation) time to fracture healing was significantly better in the TPTD group (5.4 ± 1.5 months) than in the non-TPTD group (8.6 ± 4.7 months; P = 0.012), and the frequency of delayed healing or non-union was significantly lower in the TPTD group than in the non-TPTD group (P = 0.014). Subanalyses for surgically treated complete AFFs yielded similar results, but subanalyses for incomplete AFFs treated conservatively showed no significant differences between groups. TPTD treatment appears to significantly shorten the postoperative time to fracture healing and reduce rates of delayed healing or non-union after bisphosphonate-associated AFF.