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

Atypical Periprosthetic Femoral Fracture Might be Considered a Distinct Subtype of Atypical Femoral Fracture: A Retrospective Study

OBJECTIVE

The exact relationship among atypical periprosthetic femoral fractures (APFFs), typical periprosthetic femoral fractures (PFFs), and atypical femur fractures (AFFs) remains unclear. This study aimed to investigate the prevalence of APFFs among PFFs and to identify the clinical characteristics, management, and prognosis that distinguish APFFs from typical PFFs and AFFs to further determine the relationship among these three fracture types.

METHODS

In this retrospective study, we reviewed the clinical data of 117 consecutive patients who had PFFs after hip arthroplasty between January 2012 and December 2022 and further classified them into an APFF group and a typical PFF group according to the revised ASBMR diagnostic criteria for AFF. Moreover, patients who had subtrochanteric or femoral shaft fractures in the same period and met the diagnostic criteria for AFF were recruited and classified into the AFF group. Demographic information, minor features of AFF, comorbidities, history of medication usage, management, and complications were collected and compared among patients with typical PFFs, APFFs, and AFFs.

RESULTS

Eleven PFFs were identified as APFFs, and the prevalence of APFFs among PFFs was 9.4%. Significant differences were found in generalized increase in cortical thickness (p = 0.019), prodromal symptoms (p < 0.001), and the incidence of bilateral fractures (p = 0.010) among the groups, where the incidences of these minor features in the APFF group and the AFF group were higher than those in the typical PFF group. Of note, the duration of fracture healing of APFFs was significantly longer than that of typical PFFs and AFFs (p < 0.001 and p = 0.004, respectively). In addition, the APFF group and the AFF group had higher proportions of patients with rheumatoid arthritis (p = 0.004 and p = 0.027, respectively), bisphosphonate (BP) usage (p = 0.026 and p < 0.001, respectively), and longer duration of BP usage (p = 0.003 and p = 0.007, respectively) than the typical PFF group. Furthermore, significant differences were found in management (p < 0.001) and complication rate (p = 0.020) among the groups, and the rate of complications in the APFF group and the AFF group was higher than that in the typical PFF group.

CONCLUSIONS

APFFs not only fulfilled the mandatory and major diagnostic criteria for AFF but also had many clinical characteristics, management and prognosis distinguishing them from typical PFFs but resembling AFFs; hence, the diagnostic criteria for AFF might be revised to incorporate APFF as a distinct subtype of the condition.

Teriparatide Does not Have Beneficial Effects on Bone Healing in Complete Atypical Femur Fractures

Teriparatide is an anabolic drug sometimes administered to patients who have atypical femoral fracture (AFF). However, whether teriparatide has beneficial effects on bone healing remains uncertain. The present study aimed to analyze the association between teriparatide and bone healing in complete AFF. A total of 59 consecutive cases (58 patients) who underwent intramedullary nailing for complete AFF were categorized based on postoperative use of teriparatide into the non-teriparatide (non-TPTD, n = 34) and teriparatide groups (TPTD, n = 25). Time-to-bone union was evaluated and compared between the two groups. Additionally, multiple regression analysis was performed to evaluate factors affecting time-to-bone union. All participants were women, with a mean age of 77.6 years (range: 62-92). No significant difference in time-to-bone union was found between the non-TPTD and TPTD groups (5.5 months vs. 5.8 months, p = 0.359). Two patients in the non-TPTD group underwent reoperation (p = 0.503) due to failure caused by inadequate fixation, and both achieved bone healing after additional fixation with blocking screws. Multiple regression analysis revealed that the anterior gap of the fracture site postoperatively was a factor affecting time-to-bone union (p = 0.014). The beneficial effect of teriparatide on bone healing in complete AFF could not be confirmed. Additional randomized controlled trials are required. Nonetheless, appropriate techniques, including efforts to reduce the gap on the tensile side during the surgery, are important for reliable bone healing.

Does the Nonunion Rate of Atypical Femoral Fractures Differ According to Fracture Site?: A Meta-Analysis

Background

The nonunion rate for atypical femoral fractures (AFF) is known to be higher than that for typical fractures of the femur. We performed a meta-analysis to determine the incidence of nonunion necessitating reoperation following fixation for AFF and compare the rates according to the fracture site (subtrochanter or midshaft).

Methods

A total of 742 AFFs from 29 studies were included. A proportion meta-analysis utilizing a random-effects model was conducted to estimate the prevalence of nonunion. The outcomes were the incidence of reoperations that included osteosynthesis. To determine the association of nonunion with patient mean age or average duration of bisphosphonate use, meta-regression analysis was done.

Results

In proportion meta-analysis, the estimated pooled prevalence of nonunion was 7% (95% confidence interval [CI], 5%-10%) from all studies. There was a significant difference in nonunion rate between the 2 groups (I2 = 34.4%, p = 0.02); the estimated prevalence of nonunion was 15% (95% CI, 10%-20%) in subtrochanteric AFFs and 4% (95% CI, 2%-6%) in midshaft AFFs. From meta-regression analysis, significant correlations were identified between nonunion rate and patient mean age (coefficient: -0.0071, p = 0.010), but not in the average duration of bisphosphonate use (coefficient: -0.0024, p = 0.744).

Conclusions

A notable disparity existed in the nonunion rate among subtrochanteric AFFs and midshaft AFFs group. Therefore, it is critical for orthopedic surgeons to consider the complexity and challenges associated with AFF and to estimate the proper possibility of nonunion according to the fracture site.

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.

Factors Affecting the Second Complete Atypical Femoral Fracture after the First Atypical Fracture

OBJECTIVES

Atypical femoral fracture (AFF) is an atypical low-energy subtrochanteric and diaphyseal femoral fracture. Even if bone fusion is achieved in patients with AFF, the risk of AFF in the contralateral femur must be considered. This study aimed to investigate the factors affecting complete AFF in the contralateral femur and conservatively treated incomplete AFF.

SUBJECT AND METHODS

Radiographs of 111 femurs in 104 AFF cases were examined, and the femurs were classified as follows: 85 contralateral femurs with complete AFF; 18 contralateral femurs with incomplete AFF; 8 femurs with incomplete AFF without surgical treatment. Various patients' clinical data were collected, and we investigated the factors affecting the second complete AFF.

RESULTS

Complete fractures occurred in 10 (9.7%) of 103 femurs without incomplete AFF at the first visit and in 3 (37.5%) of 8 femurs with incomplete AFF. The Kaplan-Meier curve revealed that lateral cortical bone thickening and thigh pain were associated with significantly poorer prognoses (p = 0.026 and p = 0.013, respectively). Multivariate analyses revealed that eldecalcitol usage after AFF onset (p = 0.0094) and previous use of bisphosphonate or denosumab (p = 0.0126) were protective factors for second complete AFF and that the presence of thigh pain (p = 0.0134) was a risk factor for second complete AFF.

CONCLUSIONS

Eldecalcitol administration after bone union of first AFF may prevent AFF recurrence. In addition, painful incomplete AFF has a high risk of developing a complete fracture.

Effects of Teriparatide Treatment on Bone Mineral Density in Patients With Osteoporosis: A Short-Term Dose-Response Study

INTRODUCTION

Osteoporosis is a chronic bone disease that develops with a decrease in bone mineral density (BMD) along with bone mass. An essential measure in the prevention of osteoporosis is the achievement of normal peak bone mass. Teriparatide (TPTD) functions as an osteoanabolic agent, exerting a dual influence on bone remodeling by modulating both osteogenesis and osteoclastogenesis. Bone mass is determined by dual-energy x-ray absorptiometry (DEXA) quantitative CT scan and has outstanding precision (within 1% to 2%) and has the ability to show the effectiveness of drug intervention.

OBJECTIVE

To assess the effectiveness of TPTD treatment on BMD in osteoporosis patients.

MATERIALS AND METHODS

The study is a retrospective, observational, multi-center study of 378 osteoporosis patients who were treated with 20 µg of subcutaneous TPTD every day for six months. DEXA scores of the hip joints of patients were measured both before and after TPTD treatment.

RESULTS

 The DEXA scores of the total population pre and post-treatment were -2.75+0.58 and -2.15+0.95 respectively, with a p-value of <0.001, which is statistically significant. In women the pre and post-treatment scores were -2.728+0.52 and -2.276+0.49, with a significant p-value of <0.001 whereas in males, the scores were -2.756+0.72 and -2.108+1.29 respectively, with a significant p-value of <0.05.

CONCLUSION

The six-month treatment with TPTD significantly improved DEXA scores in osteoporosis patients. DEXA score's precision and sensitivity in quantifying impact contribute to effective osteoporosis management, guiding treatment strategies for better outcomes in the Indian population. Further research is warranted to see the long-term effect of TPTD.

Should nails be locked dynamically or statically in atypical femoral fractures? - A radiological analysis of time to union and reoperations in 236 displaced fractures with 4 years average follow-up

INTRODUCTION

Atypical femoral fractures (AFFs) are associated with delayed union and higher reoperation rates. Axial dynamization of intramedullary nails is hypothesized to reduce time-to-union (TTU) and fixation failure as compared to static locking.

METHODS

Consecutive acutely displaced AFFs fixed with long intramedullary nails across five centres between 2006 and 2021 with a minimum postoperative follow-up of three months were retrospectively reviewed. The primary outcome was TTU, compared between AFFs treated with dynamically or statically locked intramedullary nails. Fracture union was defined as a modified Radiographic Union Score for Tibial fractures score of 13 or greater. Secondary outcomes involved revision surgery and treatment failure, defined as non-union beyond 18 months or revision internal fixation for mechanical reasons.

RESULTS

A total of 236 AFFs (127 dynamically locked and 109 statically locked) were analysed with good interobserver reliability of fracture union assessment (intraclass correlation coefficient = 0.89; 95% CI = 0.82-0.98). AFFs treated with dynamized nails had significantly shorter median TTU (10.1 months; 95% CI = 9.24-10.96 vs 13.0 months; 95% CI = 10.60-15.40) (log-rank test, p = 0.019). Multivariate Cox regression revealed that dynamic locking was independently associated with greater likelihood of fracture union within 24 months (p = 0.009). Reoperations were less frequent in the dynamic locking group (18.9% vs 28.4%), although the difference was not statistically significant (p = 0.084). Static locking was an independent risk factor for reoperation (p = 0.049), as were varus reduction and lack of teriparatide use within three months of surgery. Static locking also demonstrated a higher frequency of treatment failure (39.4% vs 22.8%, p = 0.006) and was an independent predictor of treatment failure in logistic regression (p = 0.018). Other factors associated with treatment failure included varus reduction and open reduction.

CONCLUSIONS

Dynamic locking of intramedullary nails in AFFs is associated with faster time to union, lower rate of non-union, and fewer treatment failures.

The effect of teriparatide on fracture healing after atypical femoral fracture: A systematic review and meta-analysis

This meta-analysis demonstrated that a greater prevalence of delayed union and nonunion and a longer time to fracture healing in the group that did not receive TPTD treatment after AFFs than in the group that received TPTD treatment.

PURPOSE

To date, there is no hard evidence for medical management after atypical femoral fracture (AFF), even though weak data indicate faster healing with teriparatide (TPTD). Herein, we aimed to investigate the effect of postfracture TPTD treatment on AFF healing using a pairwise meta-analysis focusing on delayed union, nonunion, and fracture healing time.

METHODS

A systematic search of the MEDLINE (PUBMED), Embase, and Cochrane Library databases was performed for studies investigating the effect of TPTD after AFF up to October 11, 2022. We compared the incidence of delayed union and nonunion and the time of fracture healing between the TPTD ( +) and TPTD (-) groups.

RESULTS

The 6 studies analyzed a total of 214 AFF patients, including 93 who received TPTD therapy after AFF and 121 who did not. The pooled analysis showed a significantly higher rate of delayed union in the TPTD (-) group than in the TPTD ( +) group (OR, 0.24; 95% CI, 0.11-0.52; P < 0.01; I² = 0%), and a higher nonunion rate was observed in the TPTD (-) group than in the TPTD ( +) group with low heterogeneity (OR, 0.21; 95% CI, 0.06-0.78; P = 0.02; I² = 0%). The TPTD (-) group required 1.69 months longer to achieve fracture union than the TPTD ( +) group, with statistical significance (MD =  - 1.69, 95% CI: - 2.44 to - 0.95, P < 0.01; I² = 13%). Subgroup analysis for patients with complete AFF showed that the TPTD (-) group had a higher rate of delayed union with low heterogeneity (OR, 0.22; 95% CI, 0.10-0.51; P < 0.01; I² = 0%), but there was no significant difference in the nonunion rate between TPTD ( +) and TPTD (-) groups (OR, 0.35; 95% CI, 0.06-2.21; P = 0.25; I² = 0%). Fracture healing took significantly longer in the TPTD (-) group (MD =  - 1.81, 95% CI: - 2.55 to - 1.08; P < 0.01; I² = 48%). The reoperation rate showed no significant difference between the two groups (OR, 0.29; 95% CI, 0.07-1.20; P = 0.09; I² = 0%).

CONCLUSIONS

The current meta-analysis supported the hypothesis that TPTD treatment following AFF might benefit fracture healing, lowering the rate of delayed union and nonunion and shortening the fracture healing time.

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.

Simultaneous Bilateral Insufficiency Femoral Fractures After Long-Term Alendronate Treatment: A Lesson Not Yet Learned

Bisphosphonates have recently been used as a first-line treatment for osteoporosis. However, prolonged bisphosphonate use may be associated with insufficiency and atypical femoral fractures. In this case report, we present a patient with simultaneous bilateral insufficiency femoral fractures after using alendronate for 11 years, which were treated surgically. Our patient also had a history of a previous right femoral atypical fracture eight years before the latest ones, while on 3-year alendronate treatment. To our knowledge, it is the first patient reported with three atypical - insufficiency fractures covering all the anatomical areas of the proximal half of the femur after long-term bisphosphonate treatment.

Percutaneous transpedicular intracorporeal cage grafting for Kümmell disease

BACKGROUND

Osteonecrosis with progressive collapse and segmental kyphosis can lead to intersegmental instability in some osteoporotic vertebral compression fractures (OVCFs). These conditions are known as Kümmell's disease and often require anterior column reconstruction in elderly patients.

METHODS

We attempted anterior column reconstruction by percutaneous transpedicular intracorporeal cage grafting (PTICG) with short-segment pedicle screw fixation and described the steps, with discussions on the surgical indications and pros and cons.

CONCLUSION

PTICG is expected to be an alternative to vertebral anterior column reconstruction, which can preserve the thoracolumbar posterior arch and paravertebral musculature.

Open Reduction and Internal Fixation of Simultaneous, Bilateral, Atypical Femoral Shaft Fractures After Nine Years of Bisphosphonate Treatment

Bisphosphonates are generally used to treat osteoporosis and decrease the risk of femoral neck and vertebral fractures in patients with osteoporosis. Recently, it has been suggested that long-term bisphosphonate use can lead to decreased bone remodeling and an increased risk of atypical fractures. Atypical fractures often occur in the femur. The purpose of the present report is to describe a rare case of simultaneous, bilateral, atypical femoral fractures. An 80-year-old female was walking when she sustained bilateral femoral fractures that were diagnosed as atypical. The patient had received bisphosphonate treatment over the prior nine years.

The effect of osteoporosis and its treatment on fracture healing a systematic review of animal and clinical studies

Introduction

Osteoporosis is characterised by low bone mass and micro-architectural deterioration of bone structure. Its treatment is directed at the processes of bone formation or resorption, that are of utmost importance in fracture healing. We provide a comprehensive review of the literature aiming to summarize and clarify the effects of osteoporosis and its treatment on fracture healing.

Material and methods

A literature search was conducted in PubMed and Embase (OVID version). In vivo animal and human studies on long bone fractures were included. A total of 93 articles were included for this review; 23 studies on the effect of osteoporosis (18 animal and 5 clinical studies) and 70 studies on the effect of osteoporosis treatment (41 animal, 26 clinical studies and 3 meta-analyses) on fracture healing.

Results

In animal fracture models osteoporosis was associated with decreased callus formation and bone growth, bone mineral density, biomechanical strength and delayed cellular and differentiation processes during fracture healing. Two large databases identified osteoporosis as a risk factor for non-union whereas three other studies did not. One of those three studies however found a prolonged healing time in patients with osteoporosis. Anti-osteoporosis medication showed inconsistent effects on fracture healing in both non-osteoporotic and osteoporotic animal models. Only the parathyroid hormone and anti-resorption medication were related to improved fracture healing and delayed remodelling respectively. Clinical studies performed in predominantly hip and distal radius fracture patients showed no effect of bisphosphonates on fracture healing. Parathyroid hormone reduced time to union in several clinical trials performed in mainly hip fracture patients, but this did not result in decreased delayed or non-union rates.

Conclusion

Evidence that substantiates the negative influence of osteoporosis on fracture healing is predominantly from animal studies and to a lesser extent from clinical studies, since convincing clinical evidence lacks. Bisphosphonates and parathyroid hormone may be used during fracture healing, since no clear negative effect has been shown. Parathyroid hormone might even decrease time to fracture union, without decreasing union rate.

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Osteoporosis negatively influences fracture healing in animal models.

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There is no convincing evidence for a similar effect in humans.

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In animals, bisphosphonates delay bone remodelling

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In animals, parathyroid hormone improves fracture healing

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In humans, anti-osteoporotic drugs do not interfere with fracture healing.

Importance of bone turnover for therapeutic decisions in patients with CKD-MBD

Patients with chronic kidney disease-mineral and bone disorder (CKD-MBD) frequently have low bone formation rates. A recent review suggested that adynamic bone disease is not always associated with negative outcomes and therefore antiresorptive medications could be used more often. However, there is currently no evidence to support an improvement in fracture risk or mortality in patients with CKD-MBD and low bone turnover who are treated with antiresorptive medication. There is reasonable pathophysiological evidence suggesting that it may even be harmful.

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.

Exchange K-nailing, Augmented Plating Technique for Atypical Femur Diaphyseal Non-union, and Implant Failure - A Case Report

Introduction:

Atypical femoral fractures (AFFs) have an unpredictable healing process leading to higher complication rates. The literature describes various treatment modalities of non-unions in AFF. We aimed to report a case of non-union with AFF and successful union with exchange K-nailing and augmented plating techniques.

Case Report:

A 75-year-old lady with 5 years of bisphosphonate intake sustained an AFF at the mid-diaphyseal level after a trivial injury which was fixed with closed intramedullary nailing. Nine months after fixation, she developed refracture at the fracture site with segmental breakage of the nail suggesting non-union. This was managed by the removal of fibrous structures at the fracture site, removal of a broken nail, exchange K-nailing, augmented plating, and iliac crest bone grafting. The fracture healed at 15 months from the injury and achieved good functional outcome at a short-term follow-up of 1 year.

Conclusion:

Our case report highlights the challenges of treating diaphyseal AFF and the combined benefit of exchange nailing and augmented plating with bone grafting in treating AFFs with non-union.

Subtrochanteric femoral fracture with postoperative chronic osteomyelitis treated successfully by 1-stage operation: a case report

Chronic osteomyelitis is a chronic infectious disease of bone tissue, which can cause necrosis of bone and surrounding soft tissue, and is a common complication of open fracture, internal fixation, diabetic foot and blood-borne bone infection. Traumatic osteomyelitis is caused by bone tissue infection after open fracture surgery or open reduction of fracture or other bone and joint surgery. The lesion is near the fracture end. Intramedullary infection is the most serious infection in acute stage, with high fever, chills and other toxemia symptoms, similar to acute hematogenous osteomyelitis. The other is the skin and muscle necrosis infection near the fracture, which makes Fractures that lose blood supply are exposed to air and become dry and necrotic, and the course of disease turns to chronic, often accompanied by infectious nonunion or bone damage. The course of disease is prolonged and the treatment is difficult. Subtrochanteric femoral fracture with postoperative chronic osteomyelitis is a rare condition requiring complex treatment. In the present study, we report on a 49-year-old male patient who received open reduction with intramedullary nail fixation due to subtrochanteric femoral fracture, but later suffered postoperative infection and developed chronic osteomyelitis. On the basis of the complete removal of the osteomyelitis lesion, we performed a 1-stage operation where free vascularized fibula was used to repair the bone defect, followed by effective internal fixation. The patient was followed up for 24 months and finally recovered from chronic osteomyelitis, with good functional recovery of the hip joint and a Harris score of 85.

Evaluation of factors affecting the occurrence of second atypical fracture after bone union of the first atypical fracture

PURPOSE

Teriparatide is sometimes used in the treatment of atypical femoral fracture (AFF). Even if bone union is achieved, orthopedic physicians must consider the risk of relapse. This study aimed to investigate the factors affecting AFF recurrence, and to determine the appropriate treatment for osteoporosis after bone union.

METHODS

One hundred thirty-one consecutive AFFs in 113 Japanese patients were included. Eleven patients had AFF in the unaffected limb (9 patients) after the first AFF or re-fracture at the original fracture site (2 patients) after bone union of the first AFF was confirmed. We divided all patients into two groups: the second fracture group (22 AFFs in 11 patients) and non-second fracture group (109 AFFs in 102 patients). We compared clinical information between the 2 groups and investigated the factors affecting AFF recurrence using the Student t-, Welch t-, and chi-square tests.

RESULTS

Although there was no significant difference in clinical characteristics between the 2 groups, multivariate analysis of factors associated with AFF recurrence identified short duration of treatment with teriparatide and active vitamin D₃ (p = 0.0408 and 0.0366, respectively) as risk factors. Even in the analysis excluding subtrochanteric AFF, short periods of teriparatide and active vitamin D₃ administration were observed as risk factors (p = 0.0484 and 0.0346, respectively).

CONCLUSION

The administration of teriparatide for as long as possible after occurrence first AFF and the use of active vitamin D₃ after completion of teriparatide therapy may be the most effective strategy to prevent the recurrence of AFF.

Atypical femoral fracture in a metastatic bone disease patient six months after discontinuation of denosumab received sequentially to previous bisphosphonate therapy - A case report

Although, both bisphosphonates and denosumab are effective in reducing the risk of skeletal-related events in patients with metastatic bone disease, many concerns were being raised about the possible association between their use and atypical femoral fractures. A case of an atypical femoral fracture in a metastatic bone disease patient, six months after discontinuation of long-term zoledronic acid therapy and sequential treatment with denosumab is reported. After extensive laboratory and imaging examination, the fracture was classified as atypical and it was finally treated with discontinuation of denosumab, long cephalomedullary interlocking nailing and vitamin D administration. Sequential treatment with bisphosphonates and denosumab in patients with metastatic bone disease, may lead to an overlapping treatment effect, increasing bone suppression and the risk of atypical femoral fracture. In addition, discontinuation of denosumab may activate bone remodeling units in an area with microdamage accumulation in cortical bone caused by the previous bone suppression from the antiresorptive treatment. The activation of bone remodeling units may accelerate the occurrence of the atypical femoral fractures.

Treatment strategy for atypical ulnar fracture due to severely suppressed bone turnover caused by long-term bisphosphonate therapy: a case report and literature review

BACKGROUND

Atypical fractures may occur due to the combined effect of severely suppressed bone turnover (SSBT) caused by long-term bisphosphonate treatment and chronic repetitive bone microdamage. Atypical fracture of the ulna due to SSBT is a rare entity; there is no standardized treatment strategy for this condition. We successfully treated a patient with atypical fracture of the ulna. Herein, we present this patient, review the relevant literature, and discuss the treatment strategy.

CASE PRESENTATION

An 84-year-old woman presented with atypical fracture of the left ulnar shaft due to SSBT. She had a history of bisphosphonate therapy (ibandronate and alendronate) since more than 10 years; her bone turnover was severely suppressed. We performed open reduction and internal fixation (ORIF) using dual plate with some additional treatments. These included drilling and decortication, use of autogenous bone graft, low-intensity pulsed ultrasound (LIPUS) treatment, and administration of teriparatide. Finally, bone union was observed at 11 months after surgery.

CONCLUSIONS

Based on the literature review and our experience with this case, ORIF alone may not be adequate to achieve bone union; drilling, decortication, and use of cancellus bone graft is important to achieve favorable outcomes. Administration of teriparatide and LIPUS may facilitate early bone union, although further studies are required to provide more definitive evidence. Furthermore, ORIF using dual plate may help avoid implant failure owing to the long time required for bone union.

Atypical periprosthetic femoral fractures of the hip: characterisation of three cases

INTRODUCTION

Long-term use of bisphosphonates (BPs) has been associated with a specific type of tensile side femoral stress fracture known as Atypical Femoral Fracture (AFF). Theoretically periprosthetic femoral fractures (PFF) should be excluded from the diagnosis of AFF. However, emerging evidence correlates prolonged BPs use with the occurrence of a type of PFF with an atypical pattern (atypical PFF, APFF). The aim of the present study is to report 3 cases of APFF treated at a single centre.

METHODS

Clinical and radiographic records of PFF that occurred between January 2016 and August 2018 were retrospectively reviewed. All patients meeting the American Society for Bone and Mineral Research (ASBMR) criteria for definition of PFF were included. Management strategies for APFF and patient outcomes, including fracture healing and hip function (assessed by the Oxford Hip Score [OHS]) were collected.

RESULTS

3 patients in the study period were identified as APFF (1 incomplete, 2 complete). All patients were females with a mean age of 83.3 years. All patients were treated with lateral plating. The application of a contralateral strut allograft resulted in fracture healing in cases of complete fractures. Mean OHS at final follow-up was 34.3.

CONCLUSIONS

Despite occurring around a hip stem like PFF, APFF had peculiar clinical and radiographic features, making them more similar to AFF. Therefore, the orthopaedic surgeon should also consider the natural history and healing problems associated with AFF prior in order to choose the most appropriate management for APFF.

Bilateral atypical ulnar fractures occurring after long-term treatment with bisphosphonate for 7 years and with teriparatide for 2 years: a case report

Most atypical fractures associated with the long-term treatment with bisphosphonates (BP) commonly develop in the femoral shaft or subtrochanteric region. We report a rare case of bilateral atypical ulnar fractures in an 86-year-old woman with osteoporosis who finished the treatment with teriparatide for 2 years after long-term treatment with BP. She slid down from an approximately 30-cm-tall seat and slightly contused her left elbow. Plain radiography revealed that both ulnae had a noncomminuted short oblique fracture with cortical thickening and sclerosis at the fracture site. Based on the clinical and radiological findings, she was diagnosed with bilateral atypical ulnar fractures. The fracture of the left ulna was completely displaced and treated surgically. On the other hand, since the right ulna was an incomplete fracture, it was treated conservatively. During surgery, drilling with Kirschner wire and curettage were performed in the osteosclerotic lesion, and an autologous cancellous bone graft was inserted from the ipsilateral olecranon. Bone union was achieved in both fractures at 1 year after surgery. There have been no reports regarding the development of atypical ulnar fractures occurring after the long-term treatment with BP and 2-year use of teriparatide, and the treatment strategies of such fractures have not been established. If teriparatide cannot be used after occurring atypical fractures, the use of low-intensity pulsed ultrasound (LIPUS) and subsequent treatment for osteoporosis are recommended for the bone union. In addition, the treatment of the osteosclerotic lesion and rigid internal fixation are required in surgery.

Does Teriparatide Improve Fracture Union?: A Systematic Review

We conducted an updated review of the evidence of teriparatide (TPTD) for fracture healing for the following questions. (1) Does it decrease fracture healing time?; (2) Can it be an alternative treatment for nonunion?; (3) Does it aid the union of atypical femoral fracture (AFF)? We searched PubMed, EMBASE, and Cochrane Library including “Fracture” AND “nonunion” AND “Teriparatide”. In total, 57 publications met our inclusion criteria were summarized. This systemic review of the available literature revealed that TPTD works positively with regard to enhancing fracture healing time and union of AFF. There are also many case studies on the use of TPTD could be a potential new safe treatment for nonunion with no side effects. However, level 1 studies on the evidence of TPTD are still lacking so far. Over the last decade, a growing body of evidence has accumulated suggesting that TPTD can be an adjunct to enhance fracture healing or a therapeutic option to treat nonunion, but greater evidences from large volume prospective trials are needed.

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.

Detection and management of atypical femur fractures

PURPOSE OF REVIEW

This article summarizes the risk factors for atypical femur fractures (AFF), discusses current and emerging imaging modalities for early identification of AFF, and offers recommendations for prevention and management of AFFs based on the current concepts.

RECENT FINDINGS

Antiresorptive therapies are widely recommended for prevention and treatment of osteoporosis. Despite their well established effectiveness to reduce fracture risk, emerging concerns related to potential adverse effects have led to a substantial decline in the use of bisphosphonates. Although, the pathogenesis of AFF has not yet been elucidated, the bulk of evidence supports that the well known therapeutic benefits of bisphosphonate far outweigh the relatively low risk of AFFs. Recommendations for early identification of patients at risk for AFF using radiographic imaging have been established. Consensus on the management of AFF and osteoporosis in patients with AFF needs to be formulated.

SUMMARY

AFF is a rare event associated with long-term bisphosphonate therapy, which represents an apparent paradox in the management of osteoporosis. Improved understanding of pathogenetic mechanisms will be helpful in further refining of screening guidelines and standardization of management and treatment strategies.

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.

A retrospective bicenter comparative study of surgical outcomes of atypical femoral fracture: Potential effect of teriparatide on fracture healing and callus formation

BACKGROUND

The main purpose of the present study was to assess the radiologic effect of teriparatide on fracture healing, including union rate, union time, and callus formation, by quantitative measurements using serial follow-up X-ray imaging examinations in patients with complete atypical femoral fractures (AFFs) treated using closed intramedullary nailing.

METHODS

From January 2010 to October 2017, 58 consecutive patients with complete AFF who were treated with intramedullary nailing at two institutions were enrolled. Patients were classified into two groups: those who received teriparatide therapy (group A) and those who did not (group B). Teriparatide (Forsteo®; Eli Lily Co., Indianapolis, IN, USA) at a once-daily 20 μg dose was prescribed as continuous treatment of osteoporosis or with the expectation of better bone healing. Surgical outcomes, including union rate, union time, modified radiologic union score (mRUS), and callus formation at 3, 6, and 12 months postoperatively, were assessed to evaluate the effect of teriparatide on fracture healing. Quantitative measurement of callus formation was performed using the region of interest (ROI) tool in the picture archiving communication system (PACS).

RESULTS

Non-union was not observed in group A, whereas two patients had non-union in group B. Union time was 18.3 ± 4.8 (range, 12-28) weeks in group A and 23.6 ± 9.5 (range, 12-64) weeks in group B and was significantly shorter in group A than group B (p = 0.010). The average mRUSs during periods A (3-4 months postoperatively), B (6-8 months postoperatively), and C (12-14 months postoperatively) were 10.0, 13.9, and 15.9 in group A, and 8.7, 12.0, and 14.9 in group B, respectively. The average mRUSs during periods A and B were significantly different (p = 0.027 and 0.011, respectively). The medial, posterior, and total callus areas during periods A and B were also significantly greater in group A than in group B. No difference was observed in the union rate between the two groups (p = 0.492).

CONCLUSION

Teriparatide may improve callus formation and shorten union time in patients with complete diaphyseal AFF who underwent closed intramedullary nailing.

LEVEL OF EVIDENCE

Level III retrospective comparative study.

Atypical femoral fracture associated with delayed union for which the cessation of alendronate and daily administration of teriparatide contributed to fracture healing: histopathological evidence of the enhancement in bone formation parameters

A female patient with systemic lupus erythematosus developed an atypical femoral fracture of the left femur after 5 years of glucocorticoid and alendronate therapy. We performed intramedullary nailing. However, 1 week later, we performed a revision surgery using a locking plate and an iliac bone graft because of displacement at the fracture site. At this stage, alendronate was discontinued and daily teriparatide was introduced and continued for 24 months. Twenty months after the revision surgery, a re-revision surgery was performed with an iliac bone graft because of breakage of the locking plate and fracture non-union. Fracture healing was eventually obtained 15 months after the re-revision surgery. Biopsies of the ilium before the treatment and 20 months after daily teriparatide treatment were evaluated. The histology revealed that proliferating osteoid and cuboidal osteoblasts were detected around the osteoid tissue after teriparatide treatment. Bone histomorphometry findings showed that bone volume parameters and osteoid parameters prominently increased with the teriparatide treatment, but not bone resorption parameters. Laboratory findings revealed the elevation of bone-specific alkaline phosphatase (24 U/L at 7 months) compared to its pre-teriparatide level (8.1 U/L) and increased bone mineral density of the hip (from -0.2 to 0.0 in T-score). These data indicated that the discontinuation of alendronate and initiation of teriparatide treatment activated bone-forming ability in our patient and may have contributed to fracture healing.

Surgical Fixation of Atypical Femur Fractures in Bisphosphonate-treated Patients

Objective

To evaluate the outcomes of the surgical fixation of atypical femoral fractures in bisphosphonate-treated patients with an intramedullary device.

Materials and methods

This multicentric study was carried out at the department of orthopedics, Dr. Ruth Phau Civil Hospital and Medicare Hospital, Karachi, Pakistan, between 2013 and 2018. In this retrospective observational study, we reviewed 10 bisphosphonate-treated patients, fixed surgically with an intramedullary nail after presenting with radiologically characteristic atypical femur fractures identified according to the American Society for Bone and Mineral Research criteria. We excluded patients with fractures sustained by high-energy trauma, road traffic accidents, fall from a height, and those associated with underlying malignancy.

Results

A total of 11 atypical femoral fractures in 10 patients were included, all of whom were females with a mean age of 68.6 (range 57-82) years. Out of 11 fractures, 81.8% (n=9) were located in the subtrochanteric region and two were located in the femoral shaft. The mean bisphosphonate use was 58.3 months. All patients were treated with intramedullary devices; an intramedullary interlocking nail in two cases and proximal femoral nail antirotation in nine cases. The mean follow-up duration was 12 months. All fractures were united in an average time of 9.9 months (range 6 - 16 months). Implant failure and/or nonunion were not observed, whereas delayed union was noted in five patients.

Conclusion

Intramedullary fixation is a reliable method for the treatment of atypical femur fractures in bisphosphonate-treated patients owing to its intramedullary placement. These devices act as an internal splint and can provide much more axial stability, reducing the risk of implant fatigue failure due to a delay in fracture healing from prolonged bisphosphonate use.

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.

Mechanisms Underlying Normal Fracture Healing and Risk Factors for Delayed Healing

PURPOSE OF REVIEW

Substantial advances have been made in understanding the biological basis of fracture healing. Yet, it is unclear whether the presence of osteoporosis or prior or current osteoporosis therapy influences the healing process or is associated with impaired healing. This review discusses the normal process of fracture healing and the role of osteoporosis and patient-specific factors in relation to fracture repair.

RECENT FINDINGS

The definitive association of osteoporosis to impaired fracture healing remains inconclusive because of limited evidence addressing this point. eStudies testing anabolic agents in preclinical models of ovariectomized animals with induced fractures have produced mostly positive findings showing enhanced fracture repair. Prospective human clinical trials, although few in number and limited in design and to testing only one anabolic agent, have similarly yielded modestly favorable results. Interest is high for exploring currently available osteoporosis therapies for efficacy in fracture repair. Definitive data supporting their efficacy are essential in achieving approval for this indication.

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.

Current Understanding of Epidemiology, Pathophysiology, and Management of Atypical Femur Fractures

PURPOSE OF REVIEW

To summarize reports published since the 2013 American Society of Bone and Mineral Research Task Force Report on atypical femoral fractures (AFF).

RECENT FINDINGS

The absolute incidence of AFFs remains low. AFFs are primarily associated with prolonged bisphosphonate (BP) exposure, but have also been reported in unexposed patients and those receiving denosumab for osteoporosis and metastatic bone disease. Asians may be more susceptible to AFFs. Lateral femoral bowing and varus hip geometry, which increase loading forces on the lateral femoral cortex, may increase AFF risk. Altered bone material properties associated with BP therapy may predispose to AFFs by permitting initiation and increasing propagation of micro-cracks. Relevant genetic mutations have been reported in patients with AFFs. Single X-ray absorptiometry femur scans permit early detection of incomplete and/or asymptomatic AFFs. Orthopedists recommend intramedullary rods for complete AFFs and for incomplete, radiologically advanced AFFs associated with pain and/or marrow edema on MRI. Teriparatide may advance AFF healing but few data support its efficacy. Greater understanding of biological and genetic predisposition to AFF may allow characterization of individual risk prior to initiating osteoporosis therapy and help allay fear in those at low risk for this complication, which remains rare in comparison to the osteoporotic fractures prevented by antiresorptive therapy.