Risk Of Femoral Fracture Research Articles

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Purpose: The purpose of this study was to evaluate the capability of a detailed FE human body lower limb mode, called HALL (Human Active Lower Limb) model, in predicting real world pedestrian injuries and to investigate injury mechanism of pedestrian lower limb in vehicle collisions. Methods: Two real world vehicle-to-pedestrian crashes with detailed information were selected. Then, a pedestrian model combining the HALL model and the upper body of the 50th% Chinese dummy model and vehicle front models were developed to reconstruct the selected real world crashes, and the predictions of the simulations were analyzed together with observations from the accident data. Results: The results show that the predictions of the HALL model for pedestrian lower limb long bone fractures match well with the observation from hospital data of the real world accidents, and the predicted thresholds of bending moment for tibia and femur fracture are close to the average values calculated from cadaver test data. Analysis of injury mechanism of pedestrian lower limb in collisions indicates that the relatively sharper bumper of minivan type vehicles can produce concentrated loading to the lower leg and a high risk of tibia/fibula fracture, while the relatively sharper and lower bonnet leading edge may cause concentrate loading to the thigh and high femur fracture risk. Conclusions: The findings imply that the HALL model could be used as an effective tool for predicting pedestrian lower limb injuries in vehicle collisions and improvements to the minivan bumper and sedan bonnet leading edge should be concerned further in vehicle design.

In women, bisphosphonate use for ≥3 years vs.

Black DM, Geiger EJ, Eastell R, et al. Atypical femur fracture risk versus fragility fracture prevention with bisphosphonates. N Engl J Med. 2020;383:743-53. 32813950.

Long bone fractures in neonatal intensive care units of Afyonkarahisar: Five-year's experience.

Objective:To determine the incidence of long bone fractures and the clinical features related with these fractures diagnosed in neonatal intensive care units (ICUs) within the province of Afyonkarahisar in Turkey.Materials and Methods:The incidence of clavicular fractures was 2.4 in 1000 live births, and the incidence of femoral fractures was 0.32 in 1000 live births at the neonatal ICUs of Afyonkarahisar.Results:The incidence of birth trauma-related femoral fracture was 0.16 in 1000 live births, and the incidence of femoral fractures related with osteopenia of prematurity was 1.08 in 1000 live births. The mean gestational age at delivery was 39 weeks, the mean birth weight was 3.308 grams, and the male/female ratio was 3:2 for newborns with birth trauma-related femoral fractures. The mean gestational age at delivery was 30.4 weeks, the mean birth weight was 1256 grams, and the male/female ratio was 2:3 for newborns who had femoral fractures related with osteopenia of prematurity. Breech presentation was present in three newborns (60%), and cesarean section was the type of delivery in all newborns with birth trauma-related femoral fractures.Conclusion:Cesarean delivery does not reduce the risk for birth trauma-associated femoral fractures, and there is a risk for femoral fracture in cases of emergency cesarean performed for malpresentation. In order to overcome osteopenia of prematurity, calcium, phosphorus, and vitamin D should be supplemented in premature newborns with intrauterine growth retardation and receive long-term total parenteral nutrition.

Body Mass Index Vs Fracture Risk Value Primary Osteoporosis (A Case Study on Women Ages 40-45 Years at Sub-Urban Area)

This study aims to determine the relationship between BMI and fracture risk value primary osteoporosis in women aged 40-45 years in sub-urban areas. And how to optimize social activities in the environment as an effort to reduce the risk of osteoporosis. Body mass index is one of the important risk factors for osteoporosis fractures because the protective effects of subcutaneous fat tissue on bone in elderly women are calculated using FRAX®tool. The WHO in collaboration with the Sheffield's University central of metabolic bone disease has created a calculating device, the WHO risk assessment fracture tool (FRAX®tool). FRAX®tool is an online-based device used to calculate the risk of osteoporosis fractures in major bones, namely proximal humerus, wrist, vertebrae, and femur bone in the next ten years. This research is an analytical study using a cross sectional design, the number of samples is 70 female respondents aged 40–45 years in Kelurahan Melong Asih, Cimahi. The relationship between body mass index and the risk of primary osteoporosis fracture, used the rank spearman correlation test. The results of this study indicate a strong negative correlation between body mass index and the risk value of osteoporosis major, while the relationship between body mass index and risk value for osteoporosis femur fracture was found to be a moderate negative correlation. From the results of the risk of major osteoporosis fracture the lower a person's body mass index, the greater the risk of major primary osteoporosis fracture, whereas the results of the risk of femur fracture are only in obese grade II that is low, while other criteria have the same value, so it cannot be concluded if the lower a person's body mass index, the greater the risk value of the femur fracture. Keywords : Body Mass Index; Fracture Risk Value; Osteoporosis.

Femoral neck shaft angle in relation to the location of femoral stress fracture in young military recruits: femoral head versus femoral neck stress fracture

ObjectiveTo evaluate the influences of the femoral neck shaft angle (FNSA) on the location of the femoral stress fracture and to assess the potential differences in FNSA between fractured and normal femurs.Materials and methodsThirty-seven patients with femoral stress fractures who underwent both plain hip radiographs and MRI, from January 2016 to September 2019, were retrospectively included. Patients were classified as having either femoral head stress fracture (group A, n = 26) or femoral neck stress fracture (group B, n = 11). The FNSA was measured in anteroposterior (AP) hip radiograph. The Mann-Whitney U testing was used to compare the continuous values between the two groups. A receiver operating characteristic (ROC) analysis was used to evaluate the value of FNSA for predicting the risk of femoral stress fracture.ResultsThe FNSA was significantly higher in group A (median 135.9°, range 129.5–138.6°) than group B (median 124.3°, range 119.5–129.0°) (p < 0.001), but there were no significant differences in other clinical factors. Furthermore, the FNSA was significantly higher at the fractured femurs (median 135.9°, range 129.9–138.6°) than contralateral normal femurs (median 127.9°, range 123.8–132.1°) in the patients with unilateral femoral head stress fracture (n = 22) (p < 0.001). The ROC analysis revealed that the area under curve (AUC), sensitivity, and specificity for predicting the risk of femoral head stress fracture were 0.807, 72.7%, and 68.2%, respectively, at a FNSA cutoff of 131.0°.ConclusionFNSA was associated with the location of the femoral stress fracture. In addition, FNSA could serve as a predictive factor for the risk of femoral head stress fractures.

A Comparison of Lumbar Spine and Lateral Distal Femur Bone Density in Girls With Rett Syndrome

Introduction/Background: Patients with Rett syndrome (RS) are at risk for low bone mineral density (BMD) and femoral fractures. In patients with RS, assessment with lateral distal femur (LDF) dual-energy X-ray absorptiometry (DXA) is recommended and clinically relevant. This study is the first to assess LDF BMD in girls with RS, and to compare LDF BMD results with lumbar spine BMD results in RS. Method Eleven girls (mean age 8.4 yr) with molecularly diagnosed RS and clinical DXA scan(s) were identified; medical charts were retrospectively reviewed. Baseline and serial lumbar spine and LDF BMD Z-scores were evaluated based on patients’ ambulation status, presence of epilepsy, and mutation type. Results At the time of first scan, 8 of 11 patients had normal lumbar spine BMD and low LDF BMD Z-scores. Two patients had fracture history. Fully ambulatory (3) patients had higher lumbar spine and LDF BMD than partially (5) and nonambulatory (3) patients. Patients with epilepsy had lower average BMD at all sites. No difference was seen in lumbar spine or LDF BMD in patients with high-risk BMD mutations. Seven patients had serial DXA scans with an average observation of 5.1 yr (range 3.1 yr to 6.2 yr). Lumbar spine BMD over time was variable, while LDF bone mass accrual occurred at a lower rate than typically developing girls. Conclusion Females with RS exhibited lower BMD Z-scores at the LDF than at the lumbar spine. LDF and lumbar spine results were discordant. Ambulatory status and the presence of epilepsy were related to BMD. LDF BMD accrual deviated from normal as patients aged.

Contemporary Mortality Rate and Outcomes in Nonagenarians Undergoing Primary Total Hip Arthroplasty

BackgroundNonagenarians (90-99 years) have experienced the fastest percent growth in primary THA utilization recently. However, there are limited data on this population. This study aimed to determine the mortality rate, implant survivorship, clinical outcomes, and complications of primary THAs in nonagenarians. MethodsOur institutional total joint registry was used to identify 144 nonagenarians who underwent 149 primary THAs for osteoarthritis only between 1997 and 2017. The mean age was 92 years, with 63% being female. Mortality, revision, and reoperation were assessed using cumulative incidence with death as a competing risk and Cox regression methods. Clinical outcomes were assessed using Harris hip scores (HHSs). Cemented femoral components were used in 68%. The mean follow-up was 4 years. ResultsThe mortality rates were 6%, 8%, 14%, and 49% at 90 days, 1 year, 2 years, and 5 years, respectively. The 5-year cumulative incidences of any revision and reoperation were 1% and 4%, respectively. The mean HHS improved significantly from 48 preoperatively to 76 at 5 years (P < .001). The 5-year cumulative incidence of any complication was 69%, with the most common being periprosthetic femur fracture (7) intraoperatively, delirium (25) early postoperatively, and periprosthetic femur fracture (10) later postoperatively. Uncemented stem fixation was associated with a higher risk for intraoperative femur fracture (Hazard ratio 5, P = .04) but not with a higher 5-year periprosthetic postoperative femur fracture risk (P = .19). ConclusionNonagenarians undergoing primary THA had substantial mortality rates at 90 days (6%) and 1 year (8%). While the cumulative incidence of any revision and reoperations were low at 5 years, the high complication rate is mostly due to periprosthetic fractures. Level of evidenceLevel IV, retrospective cohort.

Femoral Fracture in Primary Soft Tissue Sarcoma Treated with Intensity-Modulated Radiation Therapy with and Without Dose Constraints.

We previously reported that the cumulative risk of femoral fracture in patients treated with intensity-modulated radiation therapy (IMRT) for thigh and groin soft tissue sarcoma (STS) is low. In the current study, we sought to evaluate the effect of radiation dose constraints on the rate of femoral fracture in a more contemporary cohort. All patients treated with IMRT for STS of the thigh or groin from 2004 to 2016 were included (n=145). Beginning in 2011, radiation dose was constrained to a mean dose of < 37Gy, volume of bone receiving ≥ 40Gy (V40Gy) < 64%, and maximum dose < 59 Gy to limit the dose to the femur. Sixty-one patients were treated before dose constraints were implemented, and 84 patients were treated after. Median follow-up for patients treated before and after constraints were implemented was 6.1 and 5.7years, respectively, and the two groups were demographically and clinically similar. On univariate analysis, the 5-year cumulative incidence of femoral fracture among patients treated with and without dose constraints was 1.8% (95% confidence interval [CI] 0.3-12.2%) versus 7.4% (95% CI 3.1-17.6%) [p=0.11, p=non-significant, respectively]. On multivariable analysis, only age ≥ 60years was significantly associated with increased risk of fracture. The risk of femoral fracture after IMRT for STS of the thigh/groin is low, and with the implementation of radiation dose constraints, the risk is < 2%. Although longer follow-up is needed, our results support the utilization of extremity sarcoma IMRT-specific dose constraints for fracture prevention.

ASSOCIATION OF ACUTE HEART FAILURE AND FEMORAL FRACTURES: A PROPENSITY-WEIGHTED ANALYSIS OF NATIONAL INPATIENT SAMPLE

SESSION TITLE: Cardiovascular Disease SESSION TYPE: Original Investigation Posters PRESENTED ON: October 18-21, 2020 PURPOSE: Heart failure in the setting of acute trauma is poorly understood. Associated large scale catecholamine surge is known to have a multitude of effects on the cardiovascular system. At our level 1 trauma center, we attempted to better characterize the correlation between acute heart failure and femoral fractures. METHODS: A composite database of National Inpatient Sample (NIS) for 2016 and 2017 was queried using ICD-10 codes to identify patients with femur fracture among a cohort of patients with acute heart failure. A propensity weighted logistic regression analysis was performed controlling for age, gender, and comorbidities. Propensity weighted cohorts were compared for correlation with acute HF [in each category of acute HF (acute, acute on chronic) and HF subtype (systolic, diastolic, combined systolic/diastolic, right heart, and takotsubo cardiomyopathy)]. RESULTS: Among a cohort of 815,899 patients with acute heart failure, a total of 3,792 patients were identified with a concurrent diagnosis of femoral fracture. Population average age was 82.19+8.8 years, 63.58% of whom were female. A propensity weighted logistic regression model using each acute heart failure subtype as a dependent variable was performed using Stata 16.1 controlling for age, gender, and comorbidity (presence of AICD, Pacemaker, history of chronic heart failure, diabetes, ischemic stroke, COPD, PVD, CKD, OSA, hypertension, CAD). Acute diastolic heart failure [OR 1.578, 95% CI(1.278-1.947), p < 0.001] and takotsubo cardiomyopathy [OR 2.041, 95% CI(1.622-2.567), p < 0.001] were found to have a strong positive correlation to femoral fracture. CONCLUSIONS: In our study, we focused on the comparison of patients with acute heart failure and the propensity for concurrent femoral fracture. A strong positive correlation with acute diastolic heart failure and takotsubo cardiomyopathy was found with femoral fractures. Patients with heart failure should be considered at higher risk for femoral fracture than the average healthy population. The increased risk can be attributed to comorbid conditions as well as the intrinsic risk posed by the pathophysiology of HF itself. Hip fractures may be an important, yet underreported contributor of mortality in HF patients. CLINICAL IMPLICATIONS: Patients with femoral fracture should be monitored closely for acute heart failure. DISCLOSURES: No relevant relationships by Krishna Akella, source=Web Response No relevant relationships by Charles Arcoleo, source=Web Response No relevant relationships by Akella Chendrasekhar, source=Web Response No relevant relationships by Priscilla Chow, source=Web Response No relevant relationships by Kashif Hussain, source=Web Response No relevant relationships by Samer Ibrahim, source=Web Response No relevant relationships by Gunjan Joshi, source=Web Response No relevant relationships by Ghulam Mujtaba, source=Web Response No relevant relationships by Rajoo Patel, source=Web Response No relevant relationships by Heidi Roppelt, source=Web Response No relevant relationships by Nandini Seshan, source=Web Response No relevant relationships by Howard Sklarek, source=Web Response No relevant relationships by Liana Tatarian, source=Web Response No relevant relationships by Daisy Young, source=Web Response

Fractures in patients with rheumatoid arthritis and end-stage renal disease.

Rheumatoid arthritis (RA) and end-stage renal disease (ESRD) both independently increase fracture risk; however, how RA and ESRD interplay to affect fracture risk is unknown. We aim to determine the association of RA with fracture in ESRD and identify risk factors for fracture in patients with RA and ESRD. A retrospective cohort study was conducted using the United States Renal Data System (USRDS) to identify ESRD adults with and without a history of RA who initiated dialysis in 2005-2008. International Classification of Diseases, 9th Revision (ICD-9) codes were used to identify fractures following start of dialysis. Risk for incident fracture was compared between those with and without RA. Potential risk factors for fracture among persons with RA and ESRD were analyzed. There were 754 persons with ESRD and RA, of whom 126 (17%) had any incident fracture. In multivariable adjusted final models, among ESRD patients, RA was an independent risk factor for hip/femur fracture (RR 1.28, 95% CI 1.01-1.64). Among persons with RA and ESRD, in final models, only corticosteroid use was a significant risk factor for both any incident (RR 2.00, 95% CI 1.40-2.87) and hip/femur (RR 1.97, 95% CI 1.24-3.11) fracture. Those with higher body mass index had a lower relative risk of hip/femur fracture (RR 0.95, 95% CI 0.91-0.99). Among ESRD patients, those with RA have a 28% increased risk for hip or other femur fracture. Use of corticosteroids is a potentially modifiable risk factor for fractures among persons with RA and ESRD.

A comprehensive genetic and epidemiological association analysis of vitamin D with common diseases/traits in the UK Biobank.

Vitamin D has been intensively studied for its association with human health, but the scope of such association and the causal role of vitamin D remain controversial. We aim to comprehensively investigate the links between vitamin D and human health through both epidemiological and Mendelian randomization (MR) analyses. We examined the epidemiological associations between serum 25-hydroxyvitamin D (25(OH)D) concentration and 90 diseases/traits in 326,409 UK Biobank (UKBB) Europeans. The causal relations between 25(OH)D and 106 diseases/traits were investigated by performing MR analysis using genome-wide significant 25(OH)D-associated variants (N = 143) from the largest UKBB GWAS to date. In epidemiological analysis, we found 25(OH)D was associated with 45 diseases/traits across cardiovascular/metabolic diseases, psychiatric/neurological diseases, autoimmune/inflammatory diseases, cancer, musculoskeletal diseases, and quantitative traits. In MR-analysis, we presented evidence suggesting potential causal role of 25(OH)D in increasing height (β = .064, 95% confidence interval [CI] = 0.019-0.11) and preventing the risk of ovarian cancer (odds ratio [OR] = 0.96, 95% CI = 0.93-0.99), multiple sclerosis (OR = 0.96, 95% CI = 0.94-0.98), leg fracture (OR = 0.60, 95% CI = 0.45-0.80) and femur fracture (OR = 0.53, 95% CI = 0.32-0.84). These findings confirmed associations of vitamin D with a broad spectrum of diseases/traits and supported the potential causal role of vitamin D in promoting health.

Atypical Femur Fracture Risk versus Fragility Fracture Prevention with Bisphosphonates

BackgroundBisphosphonates are effective in reducing hip and osteoporotic fractures. However, concerns about atypical femur fractures have contributed to substantially decreased bisphosphonate use, and the incidence of hip fractures may be increasing. Important uncertainties remain regarding the association between atypical femur fractures and bisphosphonates and other risk factors.MethodsWe studied women 50 years of age or older who were receiving bisphosphonates and who were enrolled in the Kaiser Permanente Southern California health care system; women were followed from January 1, 2007, to November 30, 2017. The primary outcome was atypical femur fracture. Data on risk factors, including bisphosphonate use, were obtained from electronic health records. Fractures were radiographically adjudicated. Multivariable Cox models were used. The risk–benefit profile was modeled for 1 to 10 years of bisphosphonate use to compare associated atypical fractures with other fractures prevented.ResultsAmong 196,129 women, 277 atypical femur fractures occurred. After multivariable adjustment, the risk of atypical fracture increased with longer duration of bisphosphonate use: the hazard ratio as compared with less than 3 months increased from 8.86 (95% confidence interval [CI], 2.79 to 28.20) for 3 years to less than 5 years to 43.51 (95% CI, 13.70 to 138.15) for 8 years or more. Other risk factors included race (hazard ratio for Asians vs. Whites, 4.84; 95% CI, 3.57 to 6.56), height, weight, and glucocorticoid use. Bisphosphonate discontinuation was associated with a rapid decrease in the risk of atypical fracture. Decreases in the risk of osteoporotic and hip fractures during 1 to 10 years of bisphosphonate use far outweighed the increased risk of atypical fracture among Whites but less so among Asians. After 3 years, 149 hip fractures were prevented and 2 bisphosphonate-associated atypical fractures occurred in Whites, as compared with 91 and 8, respectively, in Asians.ConclusionsThe risk of atypical femur fracture increased with longer duration of bisphosphonate use and rapidly decreased after bisphosphonate discontinuation. Asians had a higher risk than Whites. The absolute risk of atypical femur fracture remained very low as compared with reductions in the risk of hip and other fractures with bisphosphonate treatment. (Funded by Kaiser Permanente and others.)

Biomechanical Comparison of Periprosthetic Femoral Fracture Risk in Three Femoral Components in a Sawbone Model

BackgroundThe increasing use of orthopedic total hip arthroplasty implants has led to a consequent rise in the incidence of associated periprosthetic fractures (PPFs). Analysis of the National Joint Registry data showed the choice of cemented hip stem influenced the risk of a PPF occurring. However, the effect of implant design in relation to the risk of PPFs has not been investigated. MethodsThe main objective is to compare the biomechanics of PPFs as a failure of the Exeter V40, CPT, and DePuy C-Stem stems in a composite Sawbone model to identify whether a difference in the risk of fracture exists between them. Twenty-six Sawbones were divided into 3 groups, cemented with the Stryker Exeter, Zimmer CPT, or DePuy C-Stem and then torqued to fracture. ResultsWhen compared with the Exeter, the CPT- and C-Stem-implanted Sawbone models would sustain PPFs at a statistically significantly lower rotation to failure (20.1° and 26.7° vs 33.6°, P < .01) and torque to failure (124 Nm and 143 Nm vs 174 Nm, P < .01) values. The energy release rate at failure for the Exeter was significantly higher than that for the CPT and C-Stem (61.2 Nm vs 21.8 Nm and 38.6 Nm, P < .01), which led to more comminution. ConclusionThe CPT- and C-Stem-implanted femurs, although fracturing earlier, fractured in a simple pattern with less comminution. The differences in stem design mean higher stress at the critical point of failure in the CPT implanted femur compared with the Exeter and DePuy, which is likely the reason behind the observed increased risk of PPFs with the CPT implant.

Introduction of a New Treatment Algorithm Reduces the Number of Periprosthetic Femoral Fractures After Primary Total Hip Arthroplasty in Elderly Females

BackgroundIncreasing global usage of cementless prostheses in total hip arthroplasty (THA) presents a challenge, especially for elderly patients. To reduce the risk of early periprosthetic femoral fractures (PFFs), a new treatment algorithm for females older than 60 years undergoing primary THA was introduced. The aim of this study was to determine the impact of the new treatment algorithm on the early risk of perioperative and postoperative PFFs and guideline compliance. MethodsA total of 2405 consecutive THAs that underwent primary unilateral THA at our institution were retrospectively identified in the period January 1, 2013-December 31, 2018. A new treatment algorithm was introduced on April 1, 2017 with female patients aged older than 60 years intended to receive cemented femoral components. Before this, all patients were scheduled to receive cementless femoral components. Demographic data, number of perioperative and postoperative PFFs, and surgical compliance were recorded, analyzed, and intergroup differences compared. ResultsThe utilization of cemented components in female patients older than 60 years increased from 12.3% (n = 102) to 82.5% (n = 264). In females older than 60 years, a significant reduction in the risk in early postoperative and intraoperative PFF after introduction of the new treatment algorithm was seen (4.57% vs 1.25%; P = .007 and 2.29% vs 0.31%; P = .02, respectively). Overall risk for postoperative and intraoperative fractures combined was also reduced in the entire cohort (4.1% vs 2.0%; P = .01). ConclusionUse of cemented fixation of the femoral component in female patients older than 60 years significantly reduces the number of PFFs. Our findings support use of cemented femoral fixation in elderly female patients.

Risk Factors for Revision of Polished Taper-Slip Cemented Stems for Periprosthetic Femoral Fracture After Primary Total Hip Replacement: A Registry-Based Cohort Study from the National Joint Registry for England, Wales, Northern Ireland and the Isle of Man.

Total hip replacement (THR) with a cemented polished taper-slip (PTS) femoral stem has excellent long-term results but is associated with a higher postoperative periprosthetic femoral fracture (PFF) risk compared with composite beam stems. This study aimed to identify risk factors associated with PFF revision following THR with PTS stems. In a retrospective cohort study, 299,019 primary THRs using PTS stems from the National Joint Registry for England, Wales, Northern Ireland and the Isle of Man (NJR) were included, with a median follow-up of 5.2 years (interquartile range [IQR], 3.1 to 8.2 years). The adjusted hazard ratio (HR) of PFF revision was estimated for each variable using multivariable Cox survival regression analysis. Of 299,019 THR cases, 1,055 underwent revision for PFF at a median time of 3.1 years (IQR, 1.0 to 6.1 years). The mean age (and standard deviation) was 72 ± 9.7 years, 64.3% (192,365 patients) were female, and 82.6% (247,126 patients) had an American Society of Anesthesiologists (ASA) class of 1 or 2. Variables associated with increased PFF were increasing age (HR, 1.02 per year), intraoperative fracture (HR, 2.57 [95% confidence interval (CI), 1.42 to 4.66]), ovaloid (HR, 1.96 [95% CI, 1.22 to 3.16]) and round cross-sectional shapes (HR, 9.58 [95% CI, 2.29 to 40.12]), increasing stem offset (HR, 1.07 per millimeter), increasing head size (HR, 1.04 per millimeter), THR performed from 2012 to 2016 (HR, 1.45 [95% CI, 1.18 to 1.78]), cobalt-chromium stem material (HR, 6.7 [95% CI, 3.0 to 15.4]), and cobalt-chromium stems with low-viscosity cement (HR, 22.88 [95% CI, 9.90 to 52.85]). Variables associated with a decreased risk of PFF revision were female sex (HR, 0.52 [95% CI, 0.45 to 0.59]), increasing stem length (HR, 0.97 per millimeter), and a ceramic-on-polyethylene bearing (HR, 0.55 [95% CI, 0.36 to 0.85]). Increased risk of PFF revision was associated with PTS stems that are short, have high offset, are used with large femoral heads, are made of cobalt-chromium, or have ovaloid or round cross-sectional shapes. Large increases in PFF risk were associated with cobalt-chromium stems used with low-viscosity cement. Further study is required to confirm causation. Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Total Hip Arthroplasty With Trochanteric Ostectomy for Patients With Angular Deformity of the Proximal Femur

BackgroundTotal hip arthroplasty (THA) of patients with a proximal femoral deformity is technically demanding. This deformity poses the risk of femoral fracture or perforation; stem malposition; and failed stem fixation. To insert a femoral stem in neutral position with a good fit, we removed the greater trochanter in case of a varus deformity, and the lesser trochanter in case of valgus deformity, while performing THA. We aimed to evaluate stem position, implant stability, clinical results, and radiological changes after THAs using this technique. MethodsFifteen patients (17 hips; 11 varus hips and 6 valgus hips) underwent cementless THA using the trochanteric osteotomy technique in one institution. We evaluated procedure-specific complications: intraoperative femoral fracture, stem malposition, weakness of the abductor power and limp. Modified Harris Hip Score, radiological changes, and the stability of stems were assessed at a mean of 7.1 years of follow-up (range 2.0-15.5). ResultsFemoral fracture occurred during the insertion of the stem in 4 hips. All stems were aligned in neutral position. At the latest follow-up, the mean power of the abductor was 4.3 (range 3-5). Eleven patients had slight limp and 4 patients had moderate limp. All stems had bone-ingrown stability and no stem was revised. The mean modified Harris Hip Score improved from 50 points at the preoperative evaluation to 81 points at the final follow-up. ConclusionThe trochanteric excision enabled neutral insertion of cementless stem in patients with varus/valgus deformity of the proximal femur, and THA using this technique rendered favorable results.

MON-356 Atypical Femur Fracture with Denosumab

Background: Osteoporosis (OP) is a systemic disease that is associated with increased risk for fractures. Anti-resorptive medications (ARM) are an effective modality for treatment and prevention of fractures in OP. Long-term use of ARM like bisphosphonates (BP) is associated with increased risk of atypical femoral fractures (AFF). Denosumab (DM) is monoclonal antibody that targets receptor activator of nuclear factor KB ligand (RANKL). A few cases of AFF with DM have been reported in patients who have previously been on long term BP therapy. We present a case where the patient had only received two zoledronic acid (ZA) infusions, last one three years prior to being initiated on DM and experienced AFF. Case: 73-year-old postmenopausal woman presented to the emergency room with sudden onset pain in the right thigh. Patient was standing and reaching into her closet when she felt a snap in right thigh followed by inability to move the right leg or bear weight on it. X-ray of the right femur showed a displaced femoral shaft fracture with a short transverse fracture line and a spike, without comminution.History was significant for OP for which she received raloxifene for a couple of years followed by ZA in 2013 and 2015 by her primary care. Fracture history was significant for a wrist fracture in 2015, and T12 and L1 fractures in 2017 from coughing while on Medrol dospak for an acute episode of bronchitis. In 2017, bone density showed L1-L4 T score of -2.0, the left total hip T score was -1.8 and left femoral neck T score was -2.5 consistent with OP. Work up for secondary causes of OP was unremarkable. Due to recent T12 and L1 compression fractures, she was recommended DM. She received DM in June 2018 as she was undergoing a dental implant followed by December 2018 and June 2019 and presented with the right femoral fracture in November 2019.Past history was significant for idiopathic pulmonary fibrosis which had been relatively stable without need for long-term steroid therapy. History was negative for diabetes or kidney disease. Menarche was at age 14, menopause at 52 and she did not take any hormone replacement therapy.She underwent surgical fixation with intramedullary rod. Due to concern about ARM associated sub-trochanteric fracture in the right femur, left femur was imaged. She had cortical beaking in the distal third of the left femur, and underwent prophylactic medullary nailing of the left femur as well. Conclusion: AFF are an uncommon complication of ARM used for OP. Not many cases of AFF have been reported with the use of DM and most of the reported cases are associated with prolonged BP therapy. Our case is unusual in that AFF occurred in the absence of prolonged BP therapy and raises concern that a couple of ZA infusions in the past can also increase the risk of AFF. Clinicians need to have a high index of suspicion and may consider doing femur x-rays in patients who have previously been on BP prior to starting DM.

Comparison study of bone strength of the proximal femur with and without hip osteoarthritis by computed tomography-based finite element analysis

Proximal femoral fractures are common in elderly osteoporosis patients; however, its prevalence is clinically rare in hip fracture patients with hip osteoarthritis (OA). This study aimed to evaluate bone strength of the proximal femur with or without hip OA and proximal femoral fracture risk using computed tomography (CT)-based finite element analysis (FEA). A retrospective analysis was done on CT data of 20 patients who underwent total hip arthroplasty for unilateral hip OA. Furthermore, the fracture load between OA and contralateral sides was compared and the association between fracture load and risk factor was analyzed. The fracture load was significantly higher in the OA side than that in the contralateral side (3819.5 ± 1557.8 N vs. 3224.5 ± 943.7 N, respectively; P = 0.0405). There was no significant difference in fracture load between OA and the contralateral side in Kellgren–Lawrence (KL)-3 and KL-4 grade, but the KL-4 fracture load tends to be high (P = 0.2461 and P = 0.0527, respectively). Moreover, there was no significant association between fracture load and OA severity or age. The study findings may assist in predicting bone strength and proximal femur fracture risk. The results of this FEA study indicate the bone strength of the proximal femur was affected by the severity of the osteoarthritis.

Postoperative 30-day complications after cemented/hybrid versus cementless total hip arthroplasty in osteoarthritis patients > 70 years

Background and purpose — The use of cementless total hip arthroplasty (THA) in elderly patients is debated because of increased risk of early periprosthetic femoral fractures. However, cemented femoral components carry a risk of bone cement implantation syndrome. Hence, we compared in-hospital complications, complications leading to readmission and mortality ≤ 30 days postoperatively between hybrid/cemented (cemented femoral component) vs. cementless THA in osteoarthritis patients > 70 years.Patients and methods — This is a prospective observational cohort study in 9 centers from January 2010 to August 2017. We used 30-day follow-up from the Danish National Patient Registry, patient records, and data from the Danish Hip Arthroplasty Register. Only THAs performed as a result of osteoarthritis were included.Results — 3,368 (42%) of the THAs were cemented/hybrid and 4,728 (58%) cementless. The in-hospital complication risk was 7.7% after cemented/hybrid vs. 5.3% after cementless THA (< 0.001), statistically not significant when adjusting for comorbidities (p = 0.1). There were similar risks of complications causing readmission (5.7% vs. 6.2%) and mortality ≤ 30 days (0.2% vs. 0.3%). 15 cases (0.4%) of pulmonary embolism (PE) were found after cemented/hybrid vs. 4 (0.1%) after cementless THA (p = 0.001); none occurred within 24 hours postoperatively. 2 of the PEs after cementless THA led to mortality. Cemented/hybrid THA remained significantly associated with risk of PE (RR 3.9, p = 0.02), when adjusting for comorbidities. BMI > 35 was associated with highest risk of PE (RR 5.7, p = 0.003). The risk of periprosthetic femoral fracture was 0.2% after cemented/hybrid vs. 1.5% after cementless THA (p < 0.001) and the risk of dislocations was 1.2% after cemented/hybrid THA vs. 1.8% after cementless THA (p = 0.04).Interpretation — The higher risk of PE after cemented/hybrid THA and higher risk of periprosthetic femoral fractures and dislocations after cementless THA highlights that both medically and surgically complications are related to fixation technique and have to be considered.

The limitations of today's clinical guidance: Atypical femoral fracture and long-term bone-modifying agents in the oncology setting.

While bone-modifying agents such as bisphosphonates and denosumab are crucial to preventing skeletal-related events in patients with bone metastases, the optimal duration remains undefined. Extended duration may be associated with adverse effects such as osteonecrosis of the jaw and atypical femoral fracture. Although uncommon, atypical femoral fracture represents a serious consequence of prolonged bone-modifying agent use and are characterized by a prodrome and distinct radiographic findings. The oncology setting encompasses a unique set of atypical femoral fracture risk factors and considerations, with hormonal therapy in early stage disease, bone metastases in the advanced setting, and new targeted agents that may affect bone homeostasis. As outcomes in cancer treatment continue to improve, the questions of risks versus benefits of long-term bone-modifying agents and how to mitigate atypical femoral fracture risk become increasingly pertinent.