Typical Femoral Fractures Research Articles

AFFnet - a deep convolutional neural network for the detection of atypical femur fractures from anteriorposterior radiographs

Despite well-defined criteria for radiographic diagnosis of atypical femur fractures (AFFs), missed and delayed diagnosis is common. An AFF diagnostic software could provide timely AFF detection to prevent progression of incomplete or development of contralateral AFFs. In this study, we investigated the ability for an artificial intelligence (AI)-based application, using deep learning models (DLMs), particularly convolutional neural networks (CNNs), to detect AFFs from femoral radiographs. A labelled Australian dataset of pre-operative complete AFF (cAFF), incomplete AFF (iAFF), typical femoral shaft fracture (TFF), and non-fractured femoral (NFF) X-ray images in anterior-posterior view were used for training (N = 213, 49, 394, 1359, respectively). An AFFnet model was developed using a pretrained (ImageNet dataset) ResNet-50 backbone, and a novel Box Attention Guide (BAG) module to guide the model's scanning patterns to enhance its learning. All images were used to train and internally test the model using a 5-fold cross validation approach, and further validated by an external dataset. External validation of the model's performance was conducted on a Sweden dataset comprising 733 TFF and 290 AFF images. Precision, sensitivity, specificity, F1-score and AUC were measured and compared between AFFnet and a global approach with ResNet-50. Excellent diagnostic performance was recorded in both models (all AUC >0.97), however AFFnet recorded lower number of prediction errors, and improved sensitivity, F1-score and precision compared to ResNet-50 in both internal and external testing. Sensitivity in the detection of iAFF was higher for AFFnet than ResNet-50 (82 % vs 56 %). In conclusion, AFFnet achieved excellent diagnostic performance on internal and external validation, which was superior to a pre-existing model. Accurate AI-based AFF diagnostic software has the potential to improve AFF diagnosis, reduce radiologist error, and allow urgent intervention, thus improving patient outcomes.

LBSAT140 Mortality Risk Following Atypical Femoral Fracture: A Systematic Review And Meta-analysis

Abstract Introduction Proximal femoral fracture in elderly (>60 years of age) is known to be associated with a high one-year mortality risk of 21.2% (1). Studies have shown that the mortality rate of atypical femoral fracture (AFF) may be lower than that of typical proximal femoral fracture (2), although results from existing studies are inconsistent. Therefore, we aimed to summarize all available data, using systematic review and meta-analysis, to estimate the one-year mortality risk following AFF and risk ratio of mortality following AFF versus typical femoral fracture (TFF). Methods Potentially eligible studies were identified from Medline and EMBASE databases from inception to February 2022 using a search strategy that comprised keywords "Atypical Femoral Fracture" and "Mortality". Any eligible study must consist of a cohort of patients with AFF. Then, the study must report a one-year mortality risk following AFF or effect estimates with 95% confidence intervals (95% CIs) comparing mortality risks between patients with AFF and TFF. Data were retrieved from each study and were combined using the generic inverse variance method. Results A total of 8,967 articles were identified. After two rounds of independent review by three investigators, we identified 7 studies reporting one-year mortality risks of AFF and 3 studies comparing mortality risks of AFF versus TFF. These studies were included into the meta-analysis. The pooled one-year mortality risk following atypical femoral fracture of 0.10 (95% CI, 0. 05 - 0.16; with high heterogeneity, I2 93.3%). The funnel plot was asymmetric in favor of studies that reported high one-year mortality risks. In the meta-analysis comparing the mortality risks following AFF versus TFF, no significant difference in mortality risks was found between the two conditions, with the pooled risk ratio of 0.98 (95% CI 0.78 - 1.25; with high heterogeneity, I2 96.8%). Conclusion This systematic review and meta-analysis revealed that the one-year mortality risk following AFF was approximately 10%, which may be lower than the reported mortality risk after typical hip fracture of around 20% (1). However, no significant difference was found in the meta-analysis of studies that compared the mortality risks of the two conditions, suggesting the | need for further investigation. The results will be useful for risk-benefit discussions on initiation of antiresorptive and anabolic osteoporotic therapy.

Incidence of Atypical Femoral Fractures in Patients on Osteoporosis Therapy-A Registry-Based Cohort Study.

ABSTRACTAtypical femoral fractures (AFFs) have been reported in patients taking bisphosphonates (BPs) for osteoporosis therapy but also in patients with no exposure to these drugs. In contrast, less is known about the incidence of AFFs in patients taking denosumab. This registry‐based cohort study analyzed the incidence of AFFs in patients with suspected or confirmed osteoporosis who were included in the osteoporosis register of the Swiss Society of Rheumatology between January 2015 and September 2019. Statistical analyses included incidence rates, rate ratios, and hazard ratios for AFFs, and considered sequential therapies and drug holidays as time‐dependent covariates. Among the 9956 subjects in the cohort, 53 had subtrochanteric or femoral shaft fractures. Ten fractures occurred under BP or denosumab treatment and two under teriparatide therapy. Five fractures were classified as AFFs based on the revised American Society of Bone and Mineral Research case definition of AFFs from 2014. Three AFFs occurred in women being treated with denosumab at the time of diagnosis, all with prior BP use (10, 7, and 1 years, respectively). One AFF developed in a woman receiving ibandronate and one arose in a woman receiving glucocorticoids rather than antiresorptive therapy. The incidence of AFFs per 10,000 observed patient‐years was 7.1 in patients receiving denosumab and 0.9 in patients with BP‐associated AFFs, yielding a rate ratio of 7.9 (95% confidence interval [CI] 0.63–413), p = 0.073. The risk of AFFs was not significantly higher in patients receiving denosumab therapy compared with BP therapy (hazard ratio = 7.07, 95% CI 0.74–68.01, p = 0.090). We conclude that the risk of AFFs is low in patients taking BPs, denosumab, or both sequentially. All three patients with AFFs under denosumab therapy had undergone prior BP therapy. © 2022 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Characteristics of bisphosphonate and non-bisphosphonate related atypical femoral fracture in a South East Asian population - Secondary analysis.

Studies have found that not all atypical femoral fractures (AFF) are associated with bisphosphonate (BP) use. There are limited data on AFF in non-BP patients. In this study, we characterise factors associated with BP and non-BP related AFF and its mortality in a single centre in Singapore. We conducted a cohort study of subjects above 50years old admitted to Changi General Hospital (CGH), Singapore with fragility subtrochanteric and femoral fractures from 2009 to 2015. Using the ASBMR 2014 criteria fractures are classified into atypical and typical femoral fractures. CGH uses a nationalised electronic health record that allows review of information on patient's demographics, clinical history and previous investigations. Mortality was assessed as of 31st December 2019. Between 2009 and 2015, there were 3097 hip fractures, of which 393 were subtrochanteric and femoral fractures and 69 were classified as AFF by ASBMR 2014 criteria. 35 of AFF occurred in BP exposed and 34 occurred in non-BP exposed patients. There were no significant demographic differences in patients with BP and non-BP related AFF. There were also similar incidences of type 2 diabetes, rheumatoid arthritis and glucocorticoid use. Notably, there were a higher percentage of previous fragility fractures (35.3% vs 9.4%) in BP related AFF. Time to healing of fracture was slightly longer in BP related AFF at median (3months vs 2month, p=0.02), however there were no differences in incidence of delayed healing. Mortality between BP and non-BP related AFF were similar. In a South East Asian population in Singapore, 47.8% of AFF were found to be non-BP related. We found no major demographic and clinical differences between BP and non-BP related AFF. Mortality between BP and non-BP related AFF was similar. Further studies are needed to better understand the optimal treatment of osteoporosis in AFF prone patients in the Asian population.

Mortality Risk After Atypical Femoral Fracture: A Systematic Review and Meta-analysis

ObjectiveTo summarize all available data using systematic review and meta-analysis to estimate the 1-year mortality risk after atypical femoral fracture (AFF) and risk ratio of mortality after AFF versus typical femoral fracture (TFF). MethodsPotentially eligible studies were identified from MEDLINE and Embase databases from inception to February 2022 using a search strategy that comprised the terms for “atypical femoral fracture” and “mortality.” An eligible study must consist of a cohort of patients with AFF. Then, the study must report the 1-year mortality rate after the AFF or report effect estimates with 95% confidence intervals, comparing the incident mortality between patients with AFF and TFF. Point estimates with standard errors were retrieved from each study and combined using the generic inverse variance method. ResultsA total of 8967 articles were identified. After 2 rounds of independent review by 3 investigators, we identified 7 studies reporting the 1-year mortality rate of AFFs and 3 studies comparing the mortality rate of AFF with that of TFF. Pooled analysis revealed a pooled 1-year mortality rate after an AFF of 0.10 (95% confidence interval, 0.05-0.16; I2 = 93.3%). Two studies compared the mortality risks of AFF with those of TFF and revealed conflicting results. ConclusionThe 1-year mortality rate after an AFF was approximately 10%. However, evidence is insufficient to conclude whether there was a difference in mortality risk between AFF and TFF.

Health-related quality of life outcomes after surgical treatment of atypical femur fractures: a multicenter retrospective cohort study.

ABSTRACTThe objective of this study was to examine the health‐related quality of life (HRQOL) outcomes for surgically‐treated atypical femur fractures (AFFs) compared to typical femoral diaphyseal fractures. Two large trauma center databases were retrospectively queried for surgically‐treated femur fractures. Fractures were grouped into AFFs and compared to a control cohort. Controls for the AFF group included women with diaphyseal fractures without additional AFF characteristics. Patients were contacted for administration of the Short Form‐36v2 Health Survey. Surveys were completed an average of 30.3 months (range, 6–138 months) and 25.5 months (range, 5–77 months) postoperatively for the AFF and non‐AFF groups, respectively. All patients were female, with 46 patients in the AFF and 26 patients in the non‐AFF group. The average age of the AFF group was 70.1 years compared with an average age of 67.4 years in the non‐AFF group (p = 0.287). Over 90% (91.3%) of patients in the AFF group had a history of bisphosphonate use while 26.9% of patients in the non‐AFF group had used bisphosphonates (p < 0.0001). Patients with AFF reported their postoperative physical and mental health to be no different than similarly aged patients with femoral diaphyseal fractures, as measured by the Short Form 36, version 2 (SF‐36v2) Health Survey. These data suggest that mid‐term patient‐reported quality of life outcomes are similar among women who sustain an AFF compared to a cohort of more typical femoral diaphyseal fractures. © 2021 The Authors. JBMR Plus published by Wiley Periodicals LLC. on behalf of American Society for Bone and Mineral Research.

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

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

Abstract #175 Bisphosphonate Related a Typical Femoral Fractures: Need for Heightened Awareness Regarding Diagnosis and Therapy

Abstract #175 Bisphosphonate Related a Typical Femoral Fractures: Need for Heightened Awareness Regarding Diagnosis and Therapy

Atypical diaphyseal femoral fractures: Considerations on surgical technique

In the last two decades bisphosphonates (BP) has become the mainstream therapy for osteoporosis and the benefit in reducing the incidence of fractures has been well demonstrated in several studies, together with the drug long term (5–10 years) efficacy and safety.A complication of the long-term use of bisphosphonates is a low-energy stress fractures located in the sub-trochanteric region and the femoral shaft called atypical femur fracture (AFF).These stress fractures can be seen on plain radiographs as simple transverse patterns, with unicortical beaking and hypertrophy of the diaphyseal lateral cortex. Usually a localized thigh pain in the prodromal phase may precede the fracture by months. The current surgical treatment of choice for AFFs is intramedullary nailing (IMN). However, the treatment of AFFs is associated with a higher rate of intra-operative and post-surgical complications. This is related to anatomical e biomechanical reasons. Iatrogenic fractures, deformities, medial gap opening, eccentric position of the distal nail tip with anterior cortex perforation, delayed or non-union are frequent complications of this procedure and healing rate of AFFs. The average healing time of almost 8 months for AFFs appeared to be longer than that for typical femoral fractures, which heal at an average of 3–6 months.The purpose of this study is to analyze the different surgical devices and techniques and to advance some considerations that can be useful to diminish the rate of failure and/or complications in the treatment of AFFs in both oncologic and osteoporotic patients.

Outcomes for Elderly Patients With Atypical Femoral Fractures Compared to Typical Femoral Fractures for Length of Stay, Discharge Destination, and 30-Day Mortality Rate.

Introduction:Despite increasing recognition of atypical femoral fractures (AFFs), there’s conflicting evidence about incidence, aetiology, and short-term outcomes of these injuries. This study reports the incidence of AFFs at our center and compares the early postoperative outcomes against typical femoral fractures (TFFs).Methods:A retrospective observational cohort study of patients presenting to our trauma unit between November 2015 and July 2016 was undertaken. Inclusion criteria required radiologically confirmed proximal femoral fracture, which was then categorized as AFF or TFF. Primary outcome measures included length of stay, discharge destination, and 30-day mortality.Results:Two hundred thirty-nine patients presented to our trauma unit over 9 months with either a fractured neck of femur or proximal femoral fracture. A total of 122 were identified as pertrochanteric, subtrochanteric, or proximal femoral shaft fractures of which 25 (20.5%) displayed atypical radiographic features consistent with AFF. The 2 groups were similar for average age (TFF 85.3 years vs AFF 85.0 years), gender (19% vs 16% male gender), American Society of Anaesthesiology grade (3.0 vs 3.0), cognitive score (abbreviated mental test score = 7.03 vs 7.08), and preinjury place of residence (88.9% vs 92.0% lived in own home). Typical fractures were fixed with either dynamic hip screw or intramedullary nailing, all atypical fractures were fixed with intramedullary nailing. There was no statistical difference between the 2 groups for length of stay (12.8 days vs 14.3 days; P > .05), discharge to preinjury residence (45.1% vs 36%; P > .05), or 30-day mortality (8.1% vs 12%; P > .05).Discussion:In our predominantly geriatric population atypical radiographic features were observed in around 10% of patients presenting with proximal femoral fractures or fractured neck of femur. Previous studies have reported poor outcomes for pain, mobility, and length of stay after AFF. However, we observed no difference in short-term outcome measures when compared to patients with typical proximal femoral fracture patterns at our trauma unit.Conclusion:With modern principles of trauma care outcomes achieved following AFFs may be equivalent to typical femoral fractures in the geriatric population.

A typical bilateral femoral fracture: A case report

A typical bilateral femoral fracture: A case report

Focal Cortical Thickening along the Lateral Aspect of the Proximal Femoral Shaft: A Warning Radiographic Sign for Subsequent Complete Atypical Femoral Fracture in Patients on Bisphosphonates

AbstractAtypical femoral fracture is a known complication of patients receiving long-term bisphosphonates for osteoporosis. Recognizing early radiographic features is important to provide timely care and management before the development of a more debilitating complete fracture with its associated morbidity and mortality. We report a case of a 72-year-old lady on long-term treatment with alendronate, who presented initially with groin pain and subsequently with a femoral fracture, without any major trauma. The initial radiographic finding of focal thickening along the lateral cortex of the proximal femur was missed.

Atypical femoral fractures related to bisphosphonate treatment

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. 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. 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. 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.

The Incidence of Atypical Femoral Fractures in Patients with Rheumatic Disease: Yamagata Prefectural Committee of Atypical Femoral Fractures (YamaCAFe) Study.

Atypical femoral fractures (AFFs) have been reported to occur with minimal or spontaneous subtrochanteric and femoral shaft fractures with a characteristic transverse pattern, compared with typical femoral fractures in young patients with high-energy trauma. AFFs are related to long-term use of bisphosphonates (BPs), glucocorticoids and rheumatic diseases. We have estimated a blind analysis of AFFs in rheumatic patients receiving BPs and glucocorticoids ordinary over a long time in all Yamagata prefectural area through radiographic examination. The 123 AFFs including suspected cases over six years were collected and reviewed by two independent orthopedic surgeons. We found 86 patients with a total of 99 AFFs between 2009 and 2014 (1.43 cases/100,000 person/year). Of these 99 AFFs, 11 were in 8 rheumatic patients including three patients with bilateral AFFs. The incidence of AFFs in rheumatic patients had trend to increase from 2012. The mean age of all 8 patients was 54.9 years. All 8 patients received BPs and 7/8 received prednisolone (PSL). The mean dose of PSL was 14 mg/day. Compared to patients with unilateral AFFs, those with bilateral AFFs in rheumatic patients were on a higher dose of PSL (20 mg/day vs. 7 mg/day) and had less femoral neck-shaft angle (129° vs. 136°, p < 0.05). In conclusion, the incidence of AFFs in rheumatic patients showed a trend to increase from 2012 to 2014 in Yamagata prefecture. Careful management of AFFs is of particular importance in rheumatic patients who have taken high doses of PSL and have small femoral neck-shaft angle.

Atypical Femoral Fracture

A 66-year-old woman with a 20 year treatment history of rheumatoid arthritis and systemic lupus erythematodes presented to our hospital because of right hip pain after falling. The plain radiograph showed substantial transverse subtrochanteric fracture with a medial spike (Figures 1A and 1B). She insisted that her right hip pain occurred suddenly during walking because of which she fell. It was not after but before falling that she felt an acute pain in her right hip. She had been receiving prednisolone for more than 20 years and bisphosphonate more than 8 years. Operative fixation of the fracture was performed. Her radiograph performed 5 years ago (Figure 2A) revealed the existence of a fracture line on the lateral cortex and its cortical thickness (Figure 2B). During the long-term treatment of bisphosphonate, prodromal hip pain and radiographic findings of an incomplete fracture line might predict a typical femoral fracture. atypical femoral fracture is a rare type of fracture that occurs in the regions between the subtrochanteric and supracondylar areas and initially involves the lateral femoral cortex. Physicians should perform vigilant monitoring of cortical insufficiency and atypical femur fractures in geriatric patients on long-term bisphosphonate treatment.

Atypical femoral fractures in Italy: a retrospective analysis in a large urban emergency department during a 7-year period (2007-2013).

The aim of this study was to determine the incidence of atypical femoral fractures (AFFs) seen in a large emergency department in Italy. It was a retrospective study of all men and women aged 40years or older admitted to the Emergency Department of Parma University Hospital for a femoral fracture. Cases were identified in the hospital database with use of International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) code 820 or 821 or text strings. All the radiographic images of fractures not clearly identified as proximal or condylar were retrieved and evaluated by three independent reviewers. Fractures were considered as atypical if all three reviewers agreed on at least four of five major features defined by the 2013 American Society for Bone and Mineral Research criteria. In the 7-year period (2007-2013), with a total follow-up of 1,383,154 patient-years, we found 22 AFFs in 21 patients, accounting for 7.1% of low-trauma subtrochanteric/femoral shaft fractures and 0.6% of all femoral fractures. The incidence was very low (1.6 in 100,000 patient-years in both sexes combined). In contrast, the incidence of classic fractures of the proximal end of the femur was at least two orders of magnitude higher (typical/atypical rate ratio 152). Bisphosphonate use was reported in 13 patients (62%; mean treatment duration 9years; range 5-14years). Among 286 patients with typical subtrochanteric/femoral shaft fractures, 20 were being treated with bisphosphonate (7%; odds ratio 22; 95% confidence interval 8-58; p<0.001). This study confirms the very low incidence of AFFs in the largest Italian cohort of patients to date. Even though the risk is higher in patients treated with bisphosphonates, AFFs are very rare, and typical femoral fractures are at least 100-fold more frequent.

Outcomes between older adults with atypical and typical femoral fractures are comparable

IntroductionAtypical femoral fractures (AFFs) are rare but a serious complication associated with prolonged use of bisphosphonates. However little is known about clinical outcomes of AFFs. The aim of this study is to compare the characteristics and postoperative outcomes between older patients with AFFs and typical femoral fractures (TFFs). MethodsA retrospective matched cohort study (each AFF was age- and sex-matched with three TFFs) of patients aged 65 years or older who were admitted to The Queen Elizabeth Hospital, South Australia between January 2011 and December 2013 was undertaken. Baseline characteristics of both groups were compared. The primary outcomes evaluated were level of independence in mobility at discharge and 3 months after surgery. Secondary outcomes included length of hospital stay, post-operative complications, rate of surgical revision, discharge destination (after acute hospital stay or rehabilitation), 28-day hospital readmission and 12-month mortality. ResultsTen patients (mean age: 78.1 years) with AFFs were compared with 30 matched TFFs. Patients with AFFs were predominantly female (90%) and 80% had been taking oral bisphosphonate. Nine of the AFFs had their fractures fixed with an intramedullary (IM) nail. The level of independent mobility at discharge (OR 0.31; 95%CI: 0.06–1.71; p=0.26) and at 3 months (OR 0.51; 95%CI: 0.10–2.53; p=0.47) were comparable between the two groups. Only one AFF patient treated with plate and screws required surgical revision, compared with none in the TFF group. Secondary outcomes were not significantly different between the two groups. ConclusionRecovery of mobility and reoperation rates after surgery of patients with AFFs were favourable and did not differ significantly from TFFs. Further consideration should be given to using IM fixation in the management of AFFs in older people.

Pathological Relationship of Osteomalacia at the Site of Atypical Periprosthetic Femoral Shaft Fracture after Typical Femoral Neck Fracture Occurred in the Patient with Rheumatoid Arthritis: A Case Report

Pathological Relationship of Osteomalacia at the Site of Atypical Periprosthetic Femoral Shaft Fracture after Typical Femoral Neck Fracture Occurred in the Patient with Rheumatoid Arthritis: A Case Report

Factors associated with atypical femoral fracture.

We aimed to investigate the proportion of atypical femoral fractures (AFF) among Korean femoral fracture patients and examined the factors associated with the development of AFF. Between 2003 and 2013, 607 female patients with low-energy femoral fractures who were hospitalized at a single university hospital were retrospectively enrolled in this study. Patients were classified into two groups according to the fracture site: Patients with subtrochanteric or diaphyseal femoral fractures were included in the AFF group, while patients with intertrochanteric or neck fractures were included in the typical femoral fracture (TFF) group. After comparing clinical and radiographic characteristics between groups, we used multivariable logistic regression analysis to explore risk factors for AFF. Thirty patients (4.9 %) with AFF and 577 patients (95.1 %) with TFF were identified. The AFF group was younger than the TFF group (p < 0.01), and more patients with AFF were treated with bisphosphonate (BP) (p < 0.01) or proton-pump inhibitor (p = 0.02). When comparing the radiographic parameters, the AFF group tended to have a higher cortical thickness index (p = 0.02) and lateral-to-medial cortex ratio (p < 0.01). After adjusting for clinical variables, BP use (OR 8.09, CI 3.09-21.19) and younger age (OR 1.06, CI 1.01-1.11) were associated with AFF. The proportion of AFF was 4.9 % among patients with femoral fractures. Younger age and use of BP before fracture increased the risk of development of AFF in Korean patients.

Delayed healing of lower limb fractures with bisphosphonate therapy.

Bisphosphonate therapy (BT) is used commonly in the management of osteoporosis. A systematic review was conducted investigating delayed union of lower limb, long bone fractures in patients on BT. We specifically assessed whether BT increases the risk of delayed union or non-union in lower limb, long bone fractures. A literature search was conducted in the PubMed and Embase™ on 4 November 2014. Articles that investigated lower limb fractures, history of BT and fracture union were included in the review. A total of 9,809 papers were retrieved and 14 were deemed suitable for this review. The mean time to union in patients on BT was 8.5 months. A longer time to union was reported in a study investigating BT users versus controls (6.5 vs 4.8 months respectively). The mean rate of delayed or non-union for BT associated atypical fractures was 20% per fracture. Specifically in one study, delayed union was more common in the cohort with more than three years of BT (67%) than in the group with less than three years of BT (26%). Surgical fixation was associated with improved outcomes compared with non-operative management. BT has been described to be associated with multiple adverse outcomes related to atypical fractures. Current evidence recommends operative management for this patient group. Further investigation is required to evaluate the exact effects of BT on lower limb fractures, in particular typical femoral fractures.