Lower Fracture Risk Research Articles

Bisphosphonate Use After Kidney Transplantation Is Associated with Lower Fracture Risk.

Kidney transplant recipients are at higher risk of fractures compared to the general population. The use of bisphosphonates has been shown to increase bone mineral density after transplantation but has not been shown to lower fracture rates. Here, we aim to determine if exposure to bisphosphonates associates with lower incidence of non-vertebral fractures after kidney transplantation. We conducted a retrospective review for all Southern California Kaiser Permanente kidney transplant recipients with osteoporosis transplanted between 2000 and 2019. Baseline variables were collected. Those prescribed an oral bisphosphonate were compared to those who were not. The primary outcome was non-vertebral fracture. Chi square was used to evaluate categorical variables and Wilcoxson rank sum test for continuous variables. Propensity scores were generated to balance covariates in the bisphosphonate and non-bisphosphonate groups. Cause-specific hazard and sub distribution (Fine-Gray) methods were performed for competing risk analysis. Death censored graft survival was evaluated as a secondary outcome using standard Cox regression. There were 489 patients included in the study, 203 of which were in the bisphosphonate group. The cause specific hazard model suggested a 64% lower risk of non-vertebral fracture in the bisphosphonate group (p=0.02). The Fine-Gray hazard model treating death as a competing risk did not show lower relative incidence of non-vertebral fracture. Bisphosphonate treatment was associated with lower death censored graft failure (p=0.002). Bisphosphonate use after kidney transplantation may associate with lower risk of non-vertebral fracture after transplant. Bisphosphonate use in this study was also associated with lower death censored graft failure. Caution is advised when interpreting these results given the retrospective nature of the study.

Geographical variation in osteoporosis in Australian women: a longitudinal analysis over 23years.

To determine whether the prevalence of osteoporosis, fractures, and dual-X-ray absorptiometry (DXA) differs between Australian women living in rural compared with urban areas. The Australian Longitudinal Study on Women's Health, a prospective longitudinal study of Australian women, includes a cohort of women born 1946-1951, surveyed nine times from 1996-2019. Data from administrative health records were linked to survey data. Geographic area was classified as major city, inner regional, outer regional, or remote. Generalised estimating equations (GEE) explored outcomes of osteoporosis, fracture, and DXA rates. Univariable and multivariable regression were performed and bootstrapping with 100 repetitions at 95% sampling of the original dataset to ensure robust results. A total of 13,712 women were included: 5000 (36.5%) living in major cities, 5214 (38.0%) inner regional, 2798 (20.41%) outer regional, and 700 (5.1%) remote areas. Baseline age, 47.6 (1.46) years (mean (SD)), was similar; but education, marital status, country of birth, smoking, BMI, and comorbidities varied between areas. Over 23years, 2956 (21.6%) were diagnosed with osteoporosis, 3185 (23.2%) had an incident fracture, and 8151 (59.4%) had a DXA. On univariable analysis, women living outside major cities had lower risk of osteoporosis (inner regional OR 0.92; 95% CI 0.84, 0.99; outer regional 0.70; 0.63, 0.79; remote 0.43; 0.34, 0.53), and lower risk of fractures (inner regional area OR 0.92, 95% CI 0.84, 0.99; outer regional 0.81; 0.73, 0.90; remote 0.54; 0.42, 0.67), than women living in major cities. These differences were no longer significant on multivariable analysis, suggesting differences might be related to the distribution of risk factors. Women living in inner regional and outer regional areas were significantly less likely to have a DXA, than those living in a major city (OR 0.75, 95% CI 0.70, 0.81; OR 0.72; 95% CI 0.64, 0.77, respectively), and this remained significant on multivariable analysis. Osteoporosis or fracture affected one-third of older Australian women, and women living outside major cities had lower rates of osteoporosis, fractures, and DXA completion.

Evaluation of polyaryletherketone materials as post-core abutments for removable partial dentures: A finite element analysis

ObjectiveThe purpose was to compare the biomechanical behavior of single-piece post-core restorations made from polyaryletherketone materials with fiber post-core restorations when serving as abutments for RPD using finite element analysis (FEA). MethodsPhantom maxillary central incisor and mandibular second premolar were trimmed 1-mm coronally to cemento-enamel junction; root canals were enlarged and the teeth were scanned. Data was transferred to a solid modeling software.Twenty four models, including six post-core restorations:glass-fiber post/composite core (GFH/GFL) and single-piece post-core groups as, PEKK(PKH/PKL);Ti02-reinforced PEEK(TH/TL);ceramic reinforced PEEK(CeH/CeL);carbon fiber reinforced PEEK(CaH/CaL);glass fiber reinforced PEEK(GFPH/GFPL) with hybrid ceramic/lithium disilicate crowns on each tooth were constructed.Loads of 100 N for central incisor, and 300 N for premolar in a 45°oblique direction were applied to simulate masticatory forces. Clasp removal force of a RPD was simulated as 5 N vertically.FEA was employed to evaluate the von Mises stresses.Strain at cement layer was also investigated. ResultsCaH/CaL groups revealed the lowest stress for both teeth at root while TH/TL groups revealed the highest stress. The lowest stress values in the post-core were in GFH/GFL groups while the highest stress occurred in the CaH/CaL groups for both teeth. SignificanceGlass-fiber post-cores exhibited the lowest stresses in the post under masticatory and clasp removal forces. It may suggest a potentially lower risk of post fracture compared to polyaryletherketone group materials. TiO2-reinforced PEEK post-cores exhibited the lowest stresses among PAEK materials, indicating a potentially high fracture resistance.

Finite element study of stress distribution in medial UKA under varied lower limb alignment

Knee osteoarthritis (KOA) has a high incidence among the elderly, significantly impacting their quality of life and overall health. Medial unicompartmental knee arthroplasty (UKA) is an excellent choice for treating knee single-compartment lesions, and lower limb alignment has a profound impact on medial UKA. To explore the influence of different lower limb alignments on medial UKA. In this study, we selected MR and CT data of healthy adult male knee joints to establish a complete finite element analysis (FEA) model of the knee joint. After validation, we established a finite element model of medial UKA. Subsequently, we created 60 sets of FEA models with different lower limb alignments to analyze the impact of different lower limb alignments on medial UKA. A vertical load of 1000 N was applied to the FEA models with different lower limb alignments. During the process of shifting the Mikulicz line from the midpoint of the knee joint towards the medial side, the lower limb load was primarily concentrated on the medial compartment. The stress values of the lateral meniscus, tibial cartilage, and femoral cartilage gradually decreased. ROI (region of interest) 1 and ROI 2 showed the maximum principal strain changes, while ROI 3 and ROI 4 exhibited less pronounced fluctuations, with the maximum principal strain roughly proportionally increased. During the process of shifting the Mikulicz line towards the lateral side from the midpoint of the knee joint, the stress on the lateral compartment increased observably. ROI 1, ROI 2, ROI 3, and ROI 4 showed decreased maximum principal strains, approximately inversely proportional changes, but the overall reduction was relatively small. Different lower limb alignments have a profound impact on the short- and long-term joint function after UKA. When the Mikulicz line is 10 mm inside the midpoint of the knee joint or slightly outside, there is a relatively lower risk of tibial component fractures, lower stress on the lateral compartment, and lower load on the prosthesis. During medial UKA, measures such as bone resection and prosthesis selection should be taken to ensure that the Mikulicz line is in the ideal position.

Risk of first hip fracture under treatment with zoledronic acid versus alendronate: a NOREPOS cohort study of 88,000 Norwegian men and women in outpatient care

SummaryWe aimed to investigate the risk of hip fracture associated with zoledronic acid treatment compared to alendronate on a population level. The risk of hip fracture was lower in women using zoledronic acid and higher in women who had discontinued treatment. The findings support the effectiveness of intravenous bisphosphonate.PurposeTo investigate whether zoledronic acid (ZOL) was associated with a lower risk of the first hip fracture than alendronate (ALN) in Norway using real-world data.MethodsNationwide data on drugs dispensed in outpatient pharmacies were individually linked with all hospital-treated hip fractures. Individuals aged 50–89 years without previous hip fracture were included at their first filling of a prescription for ALN or ZOL during 2005–2016. Hazard ratios (HRs) with 95% confidence intervals (95% CIs) for first hip fracture by time-varying exposure to ZOL versus ALN were estimated in sex-stratified flexible parametric survival analyses. Covariates included time-varying accumulated ALN exposure and comorbidity level expressed by the prescription-based Rx-Risk Comorbidity Index, marital status, education, and residential urbanity.ResultsOf 75,250 women who initiated treatment, 72,614 (96.5%) were exposed to ALN and 6366 (8.5%) to ZOL. Of 12,739 men who initiated treatment, 12,311 (96.6%) were exposed to ALN and 784 (6.2%) to ZOL. In women, the HR for first hip fracture was 0.75 (95% CI: 0.61–0.91) for ZOL versus ALN. In men, the corresponding HR was 0.59 (95% CI: 0.32–1.07). Discontinued treatment was associated with increased risk compared with current ALN treatment in women (HR: 1.33; 95% CI: 1.24–1.42, men: HR 1.13 (95% CI: 0.95–1.35)).ConclusionsIn women, the risk of first hip fracture when treated with ZOL was 25% lower than when treated with ALN. Discontinued treatment was associated with a 33% increase in hip fracture risk. Similar, albeit statistically non-significant, results were observed in men.

Associations of Serum Testosterone and Sex Hormone-Binding Globulin with Incident Fractures in Middle-Aged to Older Men.

As men age, circulating testosterone (T) decreases, circulating sex-hormone binding globulin (SHBG) increases, and risk of fracture increases. It is unclear if circulating T, independently of comorbidities, is associated with fracture risk in men. To determine associations for T and SHBG with incident fractures in men. We utilized the large (n=205,973 participants, 11,088 any fracture cases, 1,680 hip fracture cases, 1,366 forearm fracture cases) and well-characterized UK Biobank cohort. Associations were modelled using Cox regressions, adjusting for multiple comorbidities/covariates, imputing for missing information, and assessing non-linearity using cubic splines. For T, not considering SHBG, there was a non-linear association with hip but not forearm fractures, with the lowest risk in the second quintile. However, in models adjusted for SHBG or using calculated free T, lower T was associated with higher risk for fractures at all evaluated bone sites. Lower SHBG was strongly associated with lower risk of hip and forearm fractures (Q1 vs Q5, hip 0.55, 0.47-0.65; forearm 0.62, 0.52-0.74). Low circulating SHBG is strongly associated with low risk of fracture at all evaluated bone sites, while the associations of circulating T with fracture risk are of lesser magnitude, non-linear, inconsistent among fracture site, and affected by adjustment for SHBG. These findings demonstrate that circulating SHBG, rather than T, is a major independent biomarker of fracture risk in men. Consequently, both total T and SHBG should be assessed when examining the relationship of endogenous T concentrations with fractures in middle-aged to older men.

8377 Associations of Serum Testosterone and Sex Hormone-Binding Globulin with Incident Fractures in Middle-Aged to Older Men

Abstract Disclosure: L. Grahnemo: None. R.J. Marriott: None. K. Murray: None. L. Tyack: None. M. Nethander: None. A.M. Matsumoto: None. E.S. Orwoll: None. D. Vanderschueren: None. B.B. Yeap: None. C. Ohlsson: None. As men age, their circulating testosterone (T) decreases, circulating sex-hormone binding globulin (SHBG) increases, and risk of bone fracture increases. Unexpectedly, a recent large clinical trial reported that T treatment increased fracture risk in men. It is unclear if circulating T, independently of comorbidities, is associated with male fracture risk. We tested the hypothesis that serum T concentration is an independent risk predictor for incident bone fractures in men. We analyzed associations for T and SHBG with incident fractures in the large and well-characterized UK Biobank cohort (205,973 male participants median age 58 years, excluding men on androgen-related therapies). Baseline serum total T and SHBG were measured by immunoassay, and incident fractures documented over a median follow-up of 13.6 years (11,088 any fracture cases; 1,680 hip fracture cases; 1,366 forearm fracture cases). Associations of hormonal variables with fracture outcomes were modelled using Cox regression, adjusted for multiple comorbidities/covariates, with imputation for missing data, and non-linearity assessed using cubic splines. For total T, in multivariable models not including SHBG, there was a non-linear association with any fracture and hip fractures but not forearm fractures, with the lowest risk in the second quintile (Q2; hazard ratio (HR), 95% confidence intervals (CIs) Q2 vs Q5 any fracture 0.89, 0.84-0.94; hip fracture 0.76, 0.66-0.87; forearm fracture 0.97, 0.83-1.13). However, in multivariable models analyzing total T which were adjusted for SHBG, lower total T was associated with higher risk for fractures at all evaluated bone sites (HR, 95% CIs Q1 vs Q5 any fracture 1.24, 1.16-1.33; hip fracture 1.28, 1.08-1.51; forearm fracture 1.51, 1.25-1.82). Similar results were seen in multivariable models using calculated free T values. Lower SHBG concentration was associated with lower risk of any fracture, hip fractures, and forearm fractures, in multivariable models not including total T (HR, 95% CIs Q1 vs Q5, any fracture 0.71, 0.67-0.75; hip fracture 0.55, 0.47-0.65; forearm fracture 0.62, 0.52-0.74), with similar results following additional adjustment for total T. In conclusion, associations of total T concentrations with fracture risk without adjustment for SHBG are non-linear and inconsistent, whereas lower total T concentration, adjusted for SHBG, was independently associated with higher risks of any fracture, hip fractures, and forearm fractures. Lower circulating SHBG, without or with adjustment for total T, was strongly associated with lower risk of fractures at all three sites, consistent with SHBG being a major independent biomarker of fracture risk in men. When examining the relationship of endogenous T concentrations with health outcomes influenced by androgen-sensitive tissues in middle-aged to older men, both total T and SHBG concentrations should be assessed. Presentation: 6/2/2024

Nutrition and Osteoporosis Prevention.

Osteoporosis affects 50% of women and 20% of men after the age of 50. Fractures are associated with significant morbidity, increased mortality and altered quality of life. Lifestyle measures for fragility fracture prevention include good nutrition including adequate protein and calcium intakes, vitamin D sufficiency, and regular weight bearing physical exercise. Dietary protein is one of the most important nutritional considerations as it affects bone mineral density, trabecular and cortical microstructure, and bone strength. When calcium intake is sufficient, higher dietary protein intake is associated with lower risk of fracture. Dairy products are a valuable source of calcium and high quality protein. Dairy product consumption, particularly fermented dairy products, are associated with a lower risk of hip fracture and vegan diets are associated with increased fracture risk. Other dietary factors associated with reduced fracture risk include at least 5 servings per day of fruits and vegetables, regular tea drinking, adherence to a Mediterranean diet and other dietary patterns which provide fibers, polyphenols and fermented dairy products. Such dietary patterns may confer health benefits through their effect on gut microbiota composition and/or function. A balanced diet including minerals, protein, fruits and vegetables is an important element in the prevention of osteoporosis and of fragility fracture.

Treating Osteoporosis in Patients with Atypical Femoral Fracture.

Patients who have suffered an atypical femoral fracture while on bisphosphonates or denosumab may continue to be at risk for typical osteoporotic fractures. There are no studies to provide guidance on safe treatment for such patients. Instead, using an illustrative case, 5 principles of management are provided that may lead to decreased osteoporotic fracture risk. The first principle is to discontinue the anti-resorptive medications, which may be challenging in the patient on denosumab because of rebound vertebral fractures reported in patients stopping denosumab. The second principle is to maximize non-pharmacologic management to reduce falls and fractures. Home safety, other methods of fall risk reduction, adequate nutrition, and an exercise prescription should help reduce fracture risk. Investigating potential secondary causes of osteoporosis, particularly if the original workup was not comprehensive, is the third principle because treatment of some specific causes may lower fracture risk. Reviewing the medication list is the fourth principle, with the goal of eliminating drugs that may increase fracture risk; and considering thiazides for some patients, which may lower fracture risk. Finally, some patients may benefit from anabolic therapy. One potential (but not FDA-approved) method is to use long-term cyclic teriparatide or abaloparatide on a three-months on, three-months off schedule. Tailoring the approach to each patient is important, based on the five clinical principles, in the absence of evidence-based management recommendations.

Shear Bond Strength of Orthodontic Brackets to Resin-Infiltrated Enamel

Abstract Objectives This study aims to evaluate shear bond strength (SBS) of orthodontic brackets to enamel after resin infiltration pretreatment using different adhesive systems. Materials and Methods Sixty extracted maxillary first premolars were divided into five groups (n = 12). Group I: sound enamel + Transbond XT; group II: resin-infiltrated enamel (ICON) + Transbond XT; group III: ICON + Scotchbond Universal Plus; group IV: ICON + Assure PLUS; group V: ICON + Transbond Plus Self Etching. The SBS was measured using universal testing machine and analyzed using analysis of variance (ANOVA). The adhesive remnant index (ARI) score after debonding was determined under stereomicroscope with a 10× magnification. Statistical Analysis A one-way ANOVA and post hoc Tukey's test were used to compare the data. Further, the ARI scores were evaluated using a chi-squared test. The level of significance was set at p = 0.05. Results SBS of group I, II, III, IV, and V were 11.70 ± 3.17, 11.23 ± 3.06, 9.52 ± 1.73, 8.97 ± 1.12, and 9.14 ± 0.70 MPa, respectively. SBS of group IV and V was significantly lower than group I and II (p < 0.05). There was no significant difference in the ARI scores among the five groups (p > 0.05). Conclusion The SBS of enamel resin infiltration pretreatment depends on the adhesive system. The SBS of all groups was within adequate SBS range in clinical use. The most common ARI score was 2, which indicated lower risk of enamel fractures when debonding.

COLLARED STEMS ARE A PROTECTIVE FACTOR AGAINST EARLY PERIPROSTHETIC FRACTURES IN TOTAL HIP ARTHROPLASTY: A MULTIVARIATE ANALYSIS IN A COHORT OF 1,623 PATIENTS

The stem design in total hip arthroplasty (THA) is constantly evolving. The impact of the collar on the risk of periprosthetic fracture remains controversial. This study aimed to determine whether adding a collar to the femoral stem impacts the early periprosthetic fracture risk within 90 days of surgery.This retrospective study included 1,623 patients who underwent primary total hip arthroplasty in a single orthopedic department between January 2010 and December 2020. The inclusion criteria were uncemented stem with or without a collar, in a primary intention, without previous hip surgery with a similar “corail like” design. The assessed data were demographic characteristics (age, gender, number of obese (BMI > 30)), single or dual mobility, the surgical approach, the early complication, particularly the periprosthetic femoral fractures. Of the 1,623 patients, 1,380 received a collared stem (85%), and 243 received a collarless stem (15%). A multivariate analysis was performed to determine the collar's effect on the risk of early periprosthetic fracture (<90 days).Nine (0.55%) early periprosthetic fractures were identified in the whole cohort. There were four fractures (1.65%) in the collarless stem group and five fractures (0.36%) in the collared stem group (p=0,005). One patient required revision surgery in the collared stem group, while two patients required revision surgery in the collarless stem group. The multinomial logistic regression model indicated a statistically significant lower (p<0.05) risk of early periprosthetic fracture within 90 days of surgery in the collared stems group. No other risk factor for early periprosthetic fractures has been identified.Using collared stems in cementless THA protects early periprosthetic femoral fractures within 90 days of surgery.

THE EFFECT OF CEMENTED FEMORAL COMPONENT DESIGN AND PROPHYLACTIC WIRE PLACEMENT AGAINST EARLY PERIPROSTHETIC FEMORAL FRACTURE IN PRIMARY TOTAL HIP ARTHROPLASTY: A BIOMECHANICAL STUDY

Previous studies have highlighted differences in the risk of periprosthetic fracture between tapered slip (TS) and composite beam (CB) stems. This biomechanical study explored periprosthetic fractures around these stems and the effect of adding a 16-gauge calcar or diaphyseal wire to TS stems on their resistance to torque.A power analysis determined a sample size of 7 specimens per group, assuming a standard deviation of 14.8 Nm in peak torque, to provide 90% power to detect a difference of at least 30 Nm between groups. Twenty-one TS stems (eight alone, six with calcar wiring, seven with diaphyseal wiring placed 2 cm distal to the lesser trochanter) and seven CB stems were cemented into standard Sawbones. A servo-hydraulic test machine applied a 1000 N load with a 1-degree rotation per second until failure. The peak torque at failure was measured, and the fracture location recorded. Comparisons were performed using two-sample t-tests.CB stems exhibited a significantly higher peak torque at failure (205.3 Nm) than TS stems (159.5 Nm, p=0.020). Calcar-wire-TS (148.2 Nm, p=0.036) and diaphyseal-wire-TS (164.9 Nm, p=0.036) were both weaker than CB stems. Wired-TS stems showed no significant difference from non-wired-TS stems. Additionally, the study could not conclude that calcar wiring is stronger than diaphyseal wiring. All TS fractures occurred at the mid-stem, simulating a B-type fracture, while the addition of the diaphyseal wire shifted the fracture location more distally in four of seven stems (p=0.0699).This biomechanical study supports the clinical evidence that CB stems have stronger resistance to torque than TS stems and may explain lower risk of periprosthetic fracture. The addition of calcar or diaphyseal wires to TS stems resulted in no significant changes in peak torque to fracture. In patients at high risk of periprosthetic fracture, CB cemented stems should be considered.

Statin use associated with a reduced risk of hip fracture in patients with gout

Studies show that statins users are at reduced risk of fracture and improved bone mineral density. However, the clinical effectiveness of statin use in patients with gout has not been investigated. This retrospective cohort study used data from Taiwan's National Health Insurance Research Database, consisting of 3443 patients with gout using statins aged 50 years and above and 6886 gout patients of non-statin users matched by sex, age and propensity score. The Cox proportional hazards regression analysis showed that statin use was associated with a reduced risk of hip fracture (adjusted hazard ratio [aHR] = 0.78, 95 % confidence interval [CI] = 0.64–0.94) after controlling for potential confounding factors. The association was significant in both genders aged 50–64 years, with aHRs of near 0.35, but not in the elderly. In addition, women aged 50–64 years who used statins also exhibited a lower risk of vertebral fracture (aHR = 0.70, 95 % CI = 0.50–0.99), but not men. In conclusion, the stating use in gout patients could reduce fracture risk for younger patients. Further research is warranted to confirm these findings.

Fractures by race and ethnicity in a diverse sample of postmenopausal women: a current evaluation among Hispanic and Asian origin groups.

Using 1998-2022 Women's Health Initiative (WHI) data, our study provides contemporary fracture data by race and ethnicity, specifically focusing on Hispanic and Asian women. Fractures of interest included any clinical, hip, and major osteoporotic fractures (MOFs). We utilized the updated race and ethnicity information collected in 2003, which included seven Asian and five Hispanic origin groups. We computed crude and age-standardized fracture incidence rates per 10 000 woman-years across race and ethnic categories and by Asian and Hispanic origin. We used Cox proportional hazards model, adjusting for age and WHI clinical trial arm, to evaluate the risk of fracture (1) by race compared to White women, (2) Asian origin compared to White women, (3) Hispanic compared to non-Hispanic women, and (4) Asian and Hispanic origins compared the most prevalent origin group. Over a median (interquartile range) follow-up of 19.4 (9.2-24.2) years, 44.2% of the 160 824 women experienced any clinical fracture, including 36 278 MOFs and 8962 hip fractures. Compared to White women, Black, Pacific Islander, Asian, and multiracial women had significantly lower risk of any clinical and MOFs, while only Black and Asian women had significantly lower hip fracture risk. Within Asian women, Filipina women had 24% lower risk of any clinical fracture compared to Japanese women. Hispanic women had significantly lower risk of any clinical, hip, and MOF fractures compared to non-Hispanic women, with no differences in fracture risk observed within Hispanic origin groups. In this diverse sample of postmenopausal women, we confirmed racial and ethnic differences in fracture rates and risk, with novel findings among within Asian and Hispanic subgroups. These data can aid in future longitudinal studies evaluate contributors to racial and ethnic differences in fractures.

Association of obesity with osteoporotic fracture risk in individuals with bone metabolism-related conditions: a cross sectional analysis.

This study aimed to investigate the individual and composite associations of different indices of obesity on osteoporotic fractures at three different sites among individuals affected by conditions influencing bone metabolism. Participants were included from the National Health and Nutrition Examination Survey (NHANES), a national cross-sectional survey. BMI and WC were used separately and in combination to evaluate the presence of obesity. Obesity was defined as BMI ≥ 30 kg/m2, WC ≥ 88 cm in females, and WC ≥ 102 cm in males. Associations between obesity and osteoporotic fractures were assessed using multivariable logistic regression and OR curves. Associations modified by age, sex, race, and alcohol consumption were also evaluated. A total of 5377 participants were included in this study. In multivariable logistic regression analyses, we found that BMI, WC, BMI defining obesity, and WC defining obesity were negatively associated with hip fracture (all p < 0.05). However, harmful associations between WC and BMI defining obesity and spine fracture were found (all p < 0.05). OR curves revealed that BMI and WC had a linear relationship with hip and spine fractures (all P for non-linearity >0.05). Further analyses showed that the highest WC quartile was harmfully associated with a higher risk of spine fractures (p < 0.05). Obese participants diagnosed by both BMI and WC were less likely to have hip fractures but more likely to have spine fractures (all P for trend <0.05). A significant interaction between age (Ref: age < 50 years) and BMI and WC was detected for hip fractures (all P for interaction <0.05). In people with conditions influencing bone metabolism, obesity diagnosed by BMI and WC was associated with a lower risk of hip fracture, while obesity diagnosed by BMI and the highest WC quartile were associated with a higher risk of spine fracture.

Subsequent fracture risk in Norwegians and immigrants with an index forearm fracture: a cohort study

SummaryThe current study investigated subsequent fracture risk following a forearm fracture in three country of birth categories: Norway, Europe and North America, and other countries. Subsequent fracture risk was modestly higher in Norwegian-born individuals compared to the two other groups. Secondary fracture prevention should be recommended regardless of country background.BackgroundFracture risk is higher in patients with a previous fracture, but whether subsequent fracture risk differs by origin of birth is unknown. This study explores subsequent fracture risk in patients with an index forearm fracture according to region of birth.MethodsNationwide data on forearm fractures in patients ≥ 18 years in 2008–2019 were obtained from the Norwegian Patient Registry and Statistics Norway. Index fractures were identified by ICD-10 code S52, whereas subsequent fractures included any ICD-10 fracture code. Data on country of birth were from Statistics Norway and included three regional categories: (1) Norway, (2) other Europe and North America and (3) other countries. Direct age standardization and Cox proportional hazard regression were used to analyse the data.ResultsAmong 143,476 individuals with an index forearm fracture, 35,361 sustained a subsequent fracture. Norwegian-born forearm fracture patients had the highest subsequent fracture rates (516/10,000 person-years in women and 380 in men). People born outside Europe and North America had the lowest rates (278/10,000 person-years in women and 286 in men). Compared to Norwegian-born individuals, the hazard ratios (HRs) of subsequent fracture in individuals from Europe and North American were 0.93 (95% CI 0.88–0.98) in women and 0.85 (95% CI 0.79–0.92) in men. The corresponding HRs in individuals from other countries were 0.76 (95% CI 0.70–0.84) in women and 0.82 (95% CI 0.74–0.92) in men.ConclusionIndividuals born outside Norway had a lower subsequent fracture risk than Norwegian-born individuals; however, subsequent fracture risk increased with age in all groups. Our results indicate that secondary fracture prevention should be recommended regardless of region of origin.

Computational biomechanical study on hybrid implant materials for the femoral component of total knee replacements

Multifunctional materials have been described to meet the diverse requirements of implant materials for femoral components of uncemented total knee replacements. These materials aim to combine the high wear and corrosion resistance of oxide ceramics at the joint surfaces with the osteogenic potential of titanium alloys at the bone-implant interface. Our objective was to evaluate the biomechanical performance of hybrid material-based femoral components regarding mechanical stress within the implant during cementless implantation and stress shielding (evaluated by strain energy density) of the periprosthetic bone during two-legged squat motion using finite element modeling. The hybrid materials consisted of alumina-toughened zirconia (ATZ) ceramic joined with additively manufactured Ti–6Al–4V or Ti–35Nb–6Ta alloys. The titanium component was modeled with or without an open porous surface structure. Monolithic femoral components of ATZ ceramic or Co–28Cr–6Mo alloy were used as reference. The elasticity of the open porous surface structure was determined within experimental compression tests and was significantly higher for Ti–35Nb–6Ta compared to Ti–6Al–4V (5.2 ± 0.2 GPa vs. 8.8 ± 0.8 GPa, p < 0.001). During implantation, the maximum stress within the ATZ femoral component decreased from 1568.9 MPa (monolithic ATZ) to 367.6 MPa (Ti–6Al–4V/ATZ), 560.9 MPa (Ti–6Al–4V/ATZ with an open porous surface), 474.9 MPa (Ti–35Nb–6Ta/ATZ), and 648.4 MPa (Ti–35Nb–6Ta/ATZ with an open porous surface). The strain energy density increased at higher flexion angles for all models during the squat movement. At ∼90° knee flexion, the strain energy density in the anterior region of the distal femur increased by 25.7 % (Ti–6Al–4V/ATZ), 70.3 % (Ti–6Al–4V/ATZ with an open porous surface), 43.7 % (Ti–35Nb–6Ta/ATZ), and 82.5% (Ti–35Nb–6Ta/ATZ with an open porous surface) compared to monolithic ATZ. Thus, the hybrid material-based femoral component decreases the intraoperative fracture risk of the ATZ part and considerably reduces the risk of stress shielding of the periprosthetic bone.

Efficacy and Safety of Anti-Osteoporotic Agents across CKD Stages: A Meta-Analysis of Randomized Clinical Trials.

Osteoporosis poses a significant health concern, especially for individuals with chronic kidney disease (CKD). CKD disrupts mineral and bone metabolism, heightening the risk of fractures and complicating the management of osteoporosis. While anti-osteoporotic interventions aim to address bone health in CKD patients, ongoing research is essential to understand the comparative efficacy and safety of these medications, particularly in different CKD stages, notably in stages 4 and 5. We searched PubMed/MEDLINE, EMBASE, and the Cochrane CENTRAL for randomized controlled trials assessing the efficacy and safety of osteoporosis interventions in CKD up to June 15, 2024. The analysis utilized the pooled odds ratio (OR) along with the corresponding 95% confidence interval (CI), employing Comprehensive Meta-Analysis software, version 3.0. To assess heterogeneity in the results of individual studies, we used Cochran's Q statistic and the I2 statistic. We analyzed 12 randomized controlled trials involving 31,027 participants, revealing a significantly lower risk of vertebral fractures with anti-osteoporotic agents (teriparatide, denosumab, romosozumab, raloxifene) compared to placebo (pooled OR, 0.28 [95% CI, 0.22-0.36]). Stratification by CKD stages showed a lower risk in Stages 1-3 but no significant reduction in stages 4 and 5. Teriparatide, denosumab, and romosozumab were effective in lowering fracture risk, whereas Raloxifene showed no significant effect. The lumbar spine, femoral neck, and total hip BMD showed no significant differences between anti-osteoporotic agents (denosumab, raloxifene, risedronate, alendronate, teriparatide) and placebo. However, romosozumab demonstrated a significantly greater BMD change in all kidney function categories. No reported side effects were observed in CKD stages 1-5 across the trials. Our meta-analysis highlights the effectiveness of anti-osteoporotic agents in lowering vertebral fracture risk in CKD patients, particularly in stages 1-3. However, this benefit is not apparent in stages 4 and 5, necessitating further research. Despite the absence of reported side effects in CKD patients, clinicians should carefully assess the suitability of these medications, considering individual risks and benefits.

Lithium and the risk of fractures in patients with bipolar disorder: A population-based cohort study

Lithium is considered to be the most effective mood stabilizer for bipolar disorder. Evolving evidence suggested lithium can also regulate bone metabolism which may reduce the risk of fractures. While there are concerns about fractures for antipsychotics and mood stabilizing antiepileptics, very little is known about the overall risk of fractures associated with specific treatments. This study aimed to compare the risk of fractures in patients with bipolar disorder prescribed lithium, antipsychotics or mood stabilizing antiepileptics (valproate, lamotrigine, carbamazepine).Among 40,697 patients with bipolar disorder from 1993 to 2019 identified from a primary care electronic health record database in the UK, 13,385 were new users of mood stabilizing agents (lithium:2339; non-lithium: 11,046). Lithium was associated with a lower risk of fractures compared with non-lithium treatments (HR 0.66, 95 % CI 0.44–0.98). The results were similar when comparing lithium with prolactin raising and sparing antipsychotics, and individual antiepileptics. Lithium use may lower fracture risk, a benefit that is particularly relevant for patients with serious mental illness who are more prone to falls due to their behaviors. Our findings could help inform better treatment decisions for bipolar disorder, and lithium's potential to prevent fractures should be considered for patients at high risk of fractures.

High physical activity is associated with greater cortical bone size, better physical function, and with lower risk of incident fractures independently of clinical risk factors in older women from the SUPERB study.

The Physical Activity Scale for the Elderly (PASE) is a validated test to assess physical activity in older people. It has not been investigated if physical activity, according to PASE, is associated with fracture risk independently from the clinical risk factors (CRFs) in FRAX, bone mineral density (BMD), comorbidity, and if such an association is due to differences in physical performance or bone parameters. The purpose of this study was to evaluate if PASE score is associated with bone characteristics, physical function, and independently predicts incident fracture in 3014 75-80-yr-old women from the population-based cross-sectional SUPERB study. At baseline, participants answered questionnaires and underwent physical function tests, detailed bone phenotyping with DXA, and high-resolution peripheral quantitative CT. Incident fractures were X-ray verified. Cox regression models were used to assess the association between PASE score and incident fractures, with adjustments for CRFs, femoral neck (FN) BMD, and Charlson comorbidity index. Women were divided into quartiles according to PASE score. Quartile differences in bone parameters (1.56% for cortical volumetric BMD and 4.08% for cortical area, Q4 vs Q1, p = .007 and p = .022, respectively) were smaller than quartile differences in physical performance (27% shorter timed up and go test, 52% longer one leg standing time, Q4 vs Q1). During 8yr (median, range 0.20-9.9) of follow-up, 1077 women had any fracture, 806 a major osteoporotic fracture (MOF; spine, hip, forearm, humerus), and 236 a hip fracture. Women in Q4 vs. Q1 had 30% lower risk of any fracture, 32% lower risk of MOF, and 54% lower risk of hip fracture. These associations remained in fully adjusted models. In conclusion, high physical activity was associated with substantially better physical function and a lower risk of any fracture, MOF and hip fracture, independently of risk factors used in FRAX, FN BMD, and comorbidity.