Trabecular Bone Score Measurements Research Articles

Mild hyponatremia is not associated with degradation of trabecular bone microarchitecture despite bone mass loss.

Hyponatremia is associated with increased risk of osteoporosis and fractures. The impact of hyponatremia on non-invasive indices of bone quality, however, is unknown. To evaluate whether trabecular bone microarchitecture, assessed non-invasively by trabecular bone score (TBS), is altered in patients with hyponatremia. We conducted a cross-sectional analysis of the population-based 2005-2008 cycles of the National Health and Nutrition Examination Survey (NHANES), in which TBS measurement was performed. The main outcome measures were TBS values and bone mineral density (BMD) T-scores at the lumbar spine, total hip and femoral neck. A total of 4204 subjects aged 50 years or older were included (4041 normonatremic, 163 hyponatremic - 90.8% with mild hyponatremia). Univariate analyses did not show any difference in TBS between patients with and without hyponatremia (1.308 ± 0.145 vs 1.311 ± 0.141, p = 0.806). Hyponatremic subjects had lower BMD T-score at total hip (-0.70 ± 1.46 vs -0.13 ± 1.32, p < 0.001) and femoral neck (-1.11 ± 1.26 vs -0.72 ± 1.14, p = 0.004), while no difference was observed at lumbar spine (-0.27 ± 1.63 vs -0.31 ± 1.51, p = 0.772). After adjustment for relevant confounders, hyponatremia was confirmed as an independent predictor of lower BMD T-score at the total hip (β=-0.20, 95%CI:[-0.39, -0.02], p = 0.029), while the significance was lost at the femoral neck (p = 0.308). Again, no association between hyponatremia and lumbar spine BMD (p = 0.236) or TBS (p = 0.346) was observed. Hyponatremia, at least in mild forms, is not associated with a degradation of trabecular microarchitecture, assessed non-invasively by TBS. An independent association between hyponatremia and loss of bone mass is confirmed, particularly at the total hip.

Degenerative lumbar changes have a statistically significant but small effect on trabecular bone score (TBS)-adjusted fracture risk (FRAX).

Trabecular bone score (TBS) assesses trabecular microarchitecture at the lumbar spine and was shown to improve fracture risk prediction compared to bone mineral density (BMD) alone. We investigated whether lumbar degenerative changes (DC) affect TBS and TBS-adjusted 10-year fracture risk assessment (tool) (FRAX) estimates. All patients who underwent BMD and TBS measurements via dual-energy X-ray absorptiometry at our institution between 1/7/2020 and 1/10/2020 were retrospectively evaluated. We identified all patients who had DC in 1 or 2 vertebrae (out of L1-L4) with a BMD T score > 1 unit higher than the remaining 2 to 3 adjacent vertebrae. TBS and BMD were compared between the vertebrae with and without DC. Change in TBS as well as FRAX estimates for major osteoporotic (MOP) and hip fractures after exclusion of the degenerative vertebrae were also determined. Of the 356 eligible patients, 94 met the inclusion criteria. The mean TBS of vertebrae without DC was not significantly different from that of L1 to L4 (1.31 ± 0.12 vs 1.32 ± 0.12, respectively, P = .11). The FRAX estimates after exclusion of the degenerative vertebrae were statistically significantly higher than for L1 to L4 for both MOP and hip fractures (P = .04 and P = .01, respectively). However, the differences were very small. The mean 10-year MOP FRAX estimate after exclusion of degenerative vertebrae was 7.67% ± 4.50% versus 7.55% ± 4.36% for L1 to L4 and the mean 10-year hip FRAX estimate after exclusion of degenerative vertebrae was 2.06% ± 2.01% versus 2.02% ± 1.98% for L1 to L4. Lumbar DC have a statistically significant but only small effect on TBS-adjusted FRAX making it unnecessary to exclude the degenerative vertebrae when computing TBS.

FRAX® Adjustment Using Renormalized Trabecular Bone Score (TBS) from L1 Alone may be Optimal for Fracture Prediction: The Manitoba BMD Registry

Lumbar spine trabecular bone score (TBS) used in conjunction with FRAX® improves 10-year fracture prediction. The derived FRAX risk adjustment is based upon TBS measured from L1-L4, designated TBSL1-L4-FRAX. In prior studies, TBS measurements that include L1 and exclude L4 give better fracture stratification than L1-L4. We compared risk stratification from TBS-adjusted FRAX using TBS derived from different combinations of upper lumbar vertebral levels renormalized for level-specific differences in individuals from the Manitoba Bone Density Program aged >40 years with baseline assessment of TBS and FRAX. TBS measurements for L1-L3, L1-L2 and L1 alone were calculated after renormalization for level-specific differences. Corresponding TBS-adjusted FRAX scores designated TBSL1-L3-FRAX, TBSL1-L2-FRAX and TBSL1-FRAX were compared with TBSL1-L4-FRAX for fracture risk stratification. Incident major osteoporotic fractures (MOF) and hip fractures were assessed. The primary outcome was incremental change in area under the curve (ΔAUC). The study population included 71,209 individuals (mean age 64 years, 89.8% female). Before renormalization, mean TBS for L1-3, L1-L2 and L1 was significantly lower and TBS-adjusted FRAX significantly higher than from using TBSL1-L4. These differences were largely eliminated when TBS was renormalized for level-specific differences. During mean follow-up of 8.7 years 6745 individuals sustained incident MOF and 2039 sustained incident hip fractures. Compared with TBSL1-L4-FRAX, use of FRAX without TBS was associated with lower stratification (ΔAUC = −0.009, p < 0.001). There was progressive improvement in MOF stratification using TBSL1-L3-FRAX (ΔAUC = +0.001, p < 0.001), TBSL1-L2-FRAX (ΔAUC = +0.004, p < 0.001) and TBSL1-FRAX (ΔAUC = +0.005, p < 0.001). TBSL1-FRAX was significantly better than all other combinations for MOF prediction (p < 0.001). Incremental improvement in AUC for hip fracture prediction showed a similar but smaller trend. In conclusion, this single large cohort study found that TBS-adjusted FRAX performance for fracture prediction was improved when limited to the upper lumbar vertebral levels and was best using L1 alone.

Trabecular Bone Score Significantly Influences Treatment Decisions in Secondary Osteoporosis.

The trabecular bone score (TBS) can be determined in addition to the Dual Energy X-ray Absorptiometry (DXA) for bone mineral density (BMD) measurement to diagnose, evaluate, and stratify bone loss and decide on appropriate treatment in patients at risk. Especially in patients with secondary osteoporosis, TBS detects restricted bone quality. To investigate the influence of an additional evaluation of TBS on patients' treatment strategy decisions, we enrolled 292 patients, with a high proportion of patients with secondary osteoporosis, from one outpatient unit over one year. Patients eligible for BMD measurement had the option to opt-in for TBS measurement. We analyzed demographic data, leading diagnoses, bone metabolism parameters, and results of BMD and TBS measurements. More than 90% of patients consented to TBS measurement. TBS measurement influenced the decision in approximately 40% of patients with a treatment indication for anti-osteoporotic drugs. We demonstrate that depending on the underlying disease/risk spectrum, 21-25.5% of patients had an unremarkable BMD measurement with poor bone quality shown in the TBS measurement. In patients with secondary osteoporosis, the use of TBS supplementary to DXA seems useful to better assess fracture risk and, thus, to initiate therapy for osteoporosis in these patients in time.

Trabecular Bone Score Vertebral Exclusions Affect Risk Classification and Treatment Recommendations: The Manitoba Bmd Registry

Lumbar spine trabecular bone score (TBS), a texture measure derived from spine dual-energy x-ray absorptiometry (DXA) images, is a bone mineral density (BMD)-independent risk factor for fracture. Lumbar vertebral levels that show structural artifact are excluded from BMD measurement. TBS is relatively unaffected by degenerative artifact, and it is uncertain whether the same exclusions should be applied to TBS reporting. To gain insight into the clinical impact of vertebral exclusion on TBS, we examined the effect of lumbar vertebral exclusions in routine clinical practice on tertile-based TBS categorization and TBS adjusted FRAX-based treatment recommendations. The study population consisted of 71,209 individuals aged 40 years and older with narrow fan-beam spine DXA examinations and retrospectively-derived TBS. During BMD reporting, 34.3% of the scans had one or more vertebral exclusions for structural artifact. When TBS was derived from the same vertebral levels used for BMD reporting, using fixed L1-L4 tertile cutoffs (1.23 and 1.31 from the McCloskey meta-analysis) reclassified 17.9% to a lower and 6.5% to a higher TBS category, with 75.6% unchanged. Reclassification was reduced from 24.4% overall to 17.2% when level-specific tertile cutoffs from the software manufacturer were used. Treatment reclassification based upon FRAX major osteoporotic fracture probability occurred in 2.9% overall, but in 9.6% of those with baseline risk ≥15%. For treatment based upon FRAX hip fracture probability, reclassification occurred in 3.4% overall, but in 10.4% in those with baseline risk ≥2%. In summary, lumbar spine TBS measurements based upon vertebral levels other than L1-L4 can alter the tertile category and treatment recommendations based upon TBS-adjusted FRAX calculation, especially for those close to or exceeding the treatment cut-off. Manufacturer level-specific tertile cut-offs should be used if vertebral exclusions are applied.

Bone density and trabecular bone score to predict fractures in adults aged 20-39years: a registry-based study.

Trabecular bone score (TBS), a bone texture measurement, is associated with fracture risk independent of bone mineral density (BMD) in older adults. In adults aged 20-40years, TBS remains stable and its role in fracture risk assessment is unclear. We utilized the Manitoba Bone Density Registry to explore the relationship of fracture risk with BMD and TBS in younger adults. Women and men aged 20-39years referred for DXA testing were studied. Incident major and any fractures were captured from health records. Categories based on WHO BMD T-score classification and TBS tertile were considered using Cox regression models to estimate covariate-adjusted (including sex) hazard ratios (aHR, 95%CI) for incident fracture by category, and each SD decrement in BMD and TBS. The study included 2799 individuals (77% female, mean age 32years). Mean (SD) minimum T-score was - 0.9 (1.1) and TBS 1.355 (0.114); 7% had osteoporosis and 13% were in the lowest TBS tertile. Incident major osteoporotic fracture (MOF) and any fracture risk was elevated in those with osteopenia (aHRs 1.20/1.45) and osteoporosis (aHRs 4.60/5.16). Fracture risk was unrelated to TBS tertile. Each SD decrement in BMD was associated with increased MOF risk (aHR 1.64) and any fracture (aHR 1.71); lower TBS was unrelated to fractures. In young adults, low BMD, but not low TBS, was predictive of MOF and any fracture. Routine clinical TBS measurement is not recommended for young adults. Further study is indicated to evaluate whether TBS is beneficial in subsets of younger adults.

Vertebral Level Variations in Trabecular Bone Score and Effect on Fracture Prediction: The Manitoba BMD Registry

Trabecular bone score (TBS), a texture measure derived from spine dual-energy x-ray absorptiometry (DXA) images, is a bone mineral density (BMD)-independent risk factor for fracture. TBS is reportedly insensitive to degenerative changes, and it is uncertain whether the same rules for excluding lumbar vertebral levels from BMD measurement should be applied to TBS. The current analysis was performed to explore inter-vertebral variation in TBS measurements from L1 to L4, how this relates to clinically identified structural artifact resulting in vertebral level exclusion from BMD reporting, and area under the curve (AUC) for incident fracture. The study population comprised 70,762 individuals aged 40 years and older at the time of baseline spine DXA assessment (mean age 64.1 years, 89.7% female), among whom 24,289 (34.3%) had one or more vertebral exclusions. Both TBS and BMD showed a similar cranial/caudal inter-vertebral gradient. Compared with L1-4, TBS from L1 alone was lower (mean difference -0.096; -7.6%) while TBS from L4 alone was 0.046 (3.6%) greater, similar in those without and with visual structural artifact. During mean follow-up of 8.7 years, 6744 (9.5%) individuals sustained incident major osteoporotic fractures. TBS from L1 alone gave significantly higher AUC for incident fracture than L1-4, which was in turn significantly higher than L2, L3 and L4 alone, seen in those without and with visual structural artifact. In contrast, AUCs for BMD showed minimal variation from L1 to L4, and was higher for L1-4 than for any individual lumbar vertebral level. In summary, we found inter-vertebral TBS variations within the lumbar spine are overall similar to BMD but are relatively unaffected by visual structural artifact. Fracture outcomes showed the strongest association with TBS measured from L1 alone. Further investigation is need to understand the cause and clinical application of these differences.

Fracture Prediction from Trabecular Bone Score is Unaffected by Anti-Resorptive Treatment: A Registry-Based Cohort Study

Trabecular bone score (TBS) predicts osteoporotic fractures independent of bone mineral density (BMD) and clinical risk factors. The aim of this study was to explore whether anti-resorptive treatment affects fracture risk prediction from TBS using a large clinical registry that includes all dual-energy X-ray absorptiometry (DXA) tests for the Province of Manitoba, Canada. Cohort 1 included 53,863 individuals aged ≥ 40 years (11.4% men; mean age 64.1 years) who had not received any anti-resorptive therapy in the year prior the baseline DXA. Cohort 2 comprised 22,917 individuals aged ≥ 40 years (6% men, mean age 66.7 years) undergoing a second DXA visit. Anti-resorptive medication was initiated in the first year after DXA in 13,439 (25%) individuals from Cohort 1 (87.9% bisphosphonates); among Cohort 2 8,864 (38.7%) had received anti-resorptive medication in the year before DXA (77.8% bisphosphonates). Incident major osteoporotic fracture (MOF), hip fracture and any fracture were identified over mean follow up 8.6 and 7.0 years for Cohorts 1 and 2, respectively. Area under the curve showed significant risk stratification for all fracture types and treatment levels, whether treatment was initiated after TBS measurement (Cohort 1) or prior to TBS measurement (Cohort 2). In Cox regression models, without and with covariate adjustment, fracture prediction from TBS was unaffected by anti-resorptive medication use (p-interaction >0.5 for all analyses). In conclusion, TBS was a robust predictor of fracture in models adjusted for clinical risk factors and BMD. The use of anti-resorptive therapy, either in the year before or following TBS measurement, did not attenuate fracture risk prediction by TBS compared to untreated individuals.

Ethnicity and Fracture Risk Stratification from Trabecular Bone Score in Canadian Women: The Manitoba BMD Registry

Lumbar spine Trabecular Bone Score (TBS), a grey-level texture measure derived from spine dual-energy x-ray absorptiometry (DXA) images, is a bone mineral density (BMD)-independent risk factor for fracture. An unresolved and controversial question is whether there are ethnic differences that affect the utility of TBS for fracture risk assessment. The current analysis examined whether self-identified ethnicity (White, Asian, Black) in women age 40 years and older referred for DXA testing affected fracture risk stratification from TBS using a large clinical registry. The study population comprised 63,078 White women, 1,915 Asian women and 329 Black women (n=329) with mean follow up 9.0±5.2 years. There were between group differences in BMI (Black>White>Asian), lumbar spine fat percentage (Asian>White>Black) and lumbar spine tissue thickness (Black>White>Asian). Despite this, lumbar spine TBS was not significantly different between the subgroups, though there was a significant difference in lumbar spine and total hip BMD (Black >White>Asian). TBS provided significant stratification for MOF and any fracture for all ethnicity subgroups, and for hip fracture in White and Asian subgroups (insufficient numbers for analysis in Black women). No significant difference in White vs. Asian or White vs. Black women were identified using a Bonferroni adjusted p-value. In summary, we found that lumbar spine TBS measurements were similar among White, Asian and Black women referred for DXA assessment in Manitoba, Canada. TBS and BMD measurements significantly stratified fracture risk in all three populations without a meaningful difference between groups. This suggests that TBS does not need to be used differently in White vs. non-White populations.

Trabecular Bone Score (TBS) Cross-Calibration for GE Prodigy and IDXA Scanners

Dual-energy X-ray absorptiometry (DXA) is used for osteoporosis diagnosis, fracture prediction and to monitor changes in bone mineral density (BMD). Change in DXA instrumentation requires formal cross-calibration and procedures have been described by the International Society for Clinical Densitometry. Whether procedures used for BMD cross-calibration are sufficient to ensure lumbar spine trabecular bone score (TBS) cross-calibration is currently uncertain. The Manitoba Bone Density Program underwent a program-wide upgrade in DXA instrumentation from GE Prodigy to iDXA in 2012, and a representative a sample of 108 clinic patients were scanned on both instruments. Lumbar spine TBS (L1-L4) measurements were retrospectively derived in 2013. TBS calibration phantoms were not available at our site when this was performed. We found excellent agreement for lumbar spine BMD, without deviation from the line of perfect agreement, and low random error (standard error of the estimate [SEE] 2.54% of the mean). In contrast, spine TBS (L1-L4) showed significant deviation from the line of identity: TBS(iDXA) = 0.730 x TBS(Prodigy) + 0.372 (p<0.001 for slope and intercept); SEE 5.12% of the mean with negative bias (r=-0.550). Results were worse for scans acquired in thick versus standard mode, but similar when the population was stratified as BMI < or > 35 kg/m2. In summary, it cannot be assumed that just because BMD cross-calibration is good that this applies to TBS. This supports the need for using TBS phantom calibration to accommodate between-scanner differences as part of the manufacturer's TBS software installation.

A Comparison of Bone Mineral Density and Its Predictors in HIV-Infected and HIV-Uninfected Older Men

ObjectiveBone health in older individuals with HIV infection has not been well studied. This study aimed to compare bone mineral density (BMD), trabecular bone score (TBS), and bone markers between HIV-infected men and age- and body mass index (BMI)-matched HIV-uninfected men aged ≥60 years. We investigated the associations of risk factors related to fracture with BMD, TBS, and bone markers in HIV-infected men. MethodsThis cross-sectional study included 45 HIV-infected men receiving antiretroviral therapy and 42 HIV-uninfected men. Medical history, BMD and TBS measurements, and laboratory tests related to bone health were assessed in all the participants. HIV-related factors known to be associated with bone loss were assessed in the HIV-infected men. ResultsThe mean BMD, TBS, and osteopenia or osteoporosis prevalence were similar among the cases and controls. The HIV-infected men had significantly higher mean N-terminal propeptide of type 1 procollagen and C-terminal cross-linking telopeptide of type I collagen levels. Stepwise multiple linear regression analysis demonstrated that low BMI (lumbar spine, P = .015; femoral neck, P = .018; and total hip, P = .005), high C-terminal cross-linking telopeptide of type I collagen concentration (total hip, P = .042; and TBS, P = .010), and low vitamin D supplementation (TBS, P = .035) were independently associated with low BMD and TBS. ConclusionIn older HIV-infected men with a low fracture risk, the mean BMD and TBS were similar to those of the age- and BMI-matched controls. The mean bone marker levels were higher in the HIV group. Traditional risk factors for fracture, including low BMI, high C-terminal cross-linking telopeptide of type I collagen level, and low vitamin D supplementation, were significant predictors of low BMD and TBS.

Effect of testosterone treatment on the trabecular bone score in older men with low serum testosterone.

In the Bone Trial of the Testosterone Trials, testosterone treatment increased trabecular volumetric bone mineral density (vBMD) and increased estimated bone strength as determined by finite element analysis. The trabecular bone score (TBS) is an indirect measure of vertebral bone microarchitecture. TBS predicts fracture independent of lumbar spine areal (a) BMD. The objective of this study was to examine the effect of testosterone treatment on TBS compared to its effects on vBMD and aBMD. Two hundred and eleven men were enrolled in the Bone Trial of the Testosterone Trials. Of these, 197 men had 2 repeat TBS and vBMD measurements; 105 men were allocated to receive testosterone, and 92 men to placebo for 1 year. TBS, aBMD, and vBMD were assessed at baseline and month 12. There was no difference in the percent change in TBS by randomized group: 1.6% (95% confidence intervals (CI) 0.2-3.9) in the testosterone group and 1.4% (95% CI -0.2, 3.1) in the placebo group. In contrast, vBMD increased by 6% (95% CI 4.5-7.5) in the testosterone group compared to 0.4% (95% CI -1.65-0.88) in the placebo groups. TBS is not clinically useful in monitoring the 1-year effect of testosterone treatment on bone structure in older hypogonadal men.

Trabecular Bone Score (TBS) in Primary Hyperparathyroidism (PHPT): A Useful Tool?

Primary Hyperparathyroidism (PHPT) often leads to bone loss, even in its asymptomatic presentations. Trabecular Bone Score (TBS) is a method to assess the trabecular bone structure of the spine. This study aimed to evaluate TBS measurements combined with Dual X-ray Absorptiometry (DXA) values in the search for more accurate bone fragility risk assessment among PHPT patients. From 2017 to 2019, patients diagnosed with PHPT (n = 64), before surgery, were invited to participate in this study. Bone mineral density (BMD) by DXA at the lumbar spine, total hip, femoral neck, distal third radius, and TBS were determined in patients and controls (n = 63). The vertebral fracture was defined using the Genant method in vertebral images by DXA and vertebral fracture assessment (VFA). Patients and controls did not differ in age, sex, menopausal status, or body mass index (BMI). The PHPT patients presented significantly lower BMD values than the controls in all sites evaluated. The TBS measurements were also statistically lower in PHPT patients than controls (mean TBS PHPT = 1.233 vs TBS controls = 1.280, p = 0.044). Osteoporosis was observed in 50% of PHPT patients and 26.6% of controls (p = 0.02). However, lumbar spine T-Score < -2.5 was observed only in 21.8% of PHPT patients. Vertebral fractures were detected in nine individuals (14%) from the PHPT group and four (6.3%) in the controls (p = 0.24). The TBS area under the curve (AUC) was higher than DXA AUC in all sites, for vertebral fracture assessment. The TBS AUC was significant in the PHPT group (0.75, 95% CI 0.62 - 0.88, p = 0.02) and not significant in the DXA analysis. The ROC curve showed that TBS values < 1.187 are associated with a significantly higher risk of vertebral fracture among PHPT patients (p = 0.02). The TBS used as a complement to DXA measurements is a useful tool which may better assess fragility risk among PHPT patients.

The role of trabecular bone score, inaddition to FRAX, for the measurementof fracture risk in patients withdegenerative lumbar spine stenosis

Objectives: To investigate the relevance of Concomitant Trabecular Bone Score (TBS) and Areal Bone Mineral Density (aBMD) assessments to estimate fracture risk in patients with Degenerative Lumbar Spine Stenosis (DLSS). Methods: A cross-sectional prospective study was performed. Dual energy X-ray absorptiometry scans of the lumbar spine and hip were acquired in 50 patients with DLSS. TBS and aBMD were calculated from the anteroposterior views of L1-L4 vertebrae. The World Health Organisation Fracture Risk Assessment Tool (FRAX) was utilised to estimate hip or Major Osteoporotic Fracture (MOF) risk. Results: L1-L4 TBS scores revealed degraded microarchitecture, (TBS ≤ 1.20), partially degraded microarchitecture (TBS >1.20 and <1.35) or normal appearances (TBS ≥ 1.35) in 9 (18%), 14 (28%) and 27 (54%) patients, respectively. L1-L4 aBMD assessment demonstrated osteoporosis (T-score ≤- 2.5), osteopenia (T-score between -1.1 and -2.4) or normal bone density in 15 (30%), 11 (22%) and 24 (48%) patients, respectively. There was no relationship seen between L1-L4 aBMD and TBS measurements (r = 0.046; p = 0.75). A negative relationship was observed between TBS and body mass index (r = -0.438; p = 0.001) andbetween L1-L4 aBMD and FRAX (r = -0.617; p < 0.001); the latter included MOF and risk of hip fracture (r = -0.497; p < 0.001).No relationship was observed between TBS and FRAX included MOF and risk of hip fracture (r = -0.118; p = 0.416 and r = -0.014; p = 0.926, respectively) Conclusion: In patients with DLSS, TBS is a reliable, strong and standalone indicator of fracture risk

Trabecular Bone Score Reference Values for Children and Adolescents According to Age, Sex, and Ancestry.

Trabecular bone score (TBS) is used for fracture prediction in adults, but its utility in children is limited by absence of appropriate reference values. We aimed to develop reference ranges for TBS by age, sex, and population ancestry for youth ages 5 to 20 years. We also investigated the association between height, body mass index (BMI), and TBS, agreement between TBS and lumbar spine areal bone mineral density (aBMD) and bone mineral apparent density (BMAD) Z-scores, tracking of TBS Z-scores over time, and precision of TBS measurements. We performed secondary analysis of spine dual-energy X-ray absorptiometry (DXA) scans from the Bone Mineral Density in Childhood Study (BMDCS), a mixed longitudinal cohort of healthy children (n= 2014) evaluated at five US centers. TBS was derived using a dedicated TBS algorithm accounting for tissue thickness rather than BMI. TBS increased only during ages corresponding to pubertal development with an earlier increase in females than males. There were no differences in TBS between African Americans and non-African Americans. We provide sex-specific TBS reference ranges and LMS values for calculation of TBS Z-scores by age and means and SD for calculation of Z-scores by pubertal stage. TBS Z-scores were positively associated with height Z-scores at some ages. TBS Z-scores explained only 27% and 17% of the variance of spine aBMD and BMAD Z-scores. Tracking of TBS Z-scores over 6 years was lower (r= 0.47) than for aBMD or BMAD Z-scores (r= 0.74 to 0.79), and precision error of TBS (2.87%) was greater than for aBMD (0.85%) and BMAD (1.22%). In sum, TBS Z-scores provide information distinct from spine aBMD and BMAD Z-scores. Our robust reference ranges for TBS in a well-characterized pediatric cohort and precision error estimates provide essential tools for clinical assessment using TBS and determination of its value in predicting bone fragility in childhood and adolescence. © 2022 American Society for Bone and Mineral Research (ASBMR).

Modestly degraded microarchitecture and high serum levels of osteopontin in Swedish females with anorexia nervosa

PurposeAdult women with long-time anorexia nervosa (AN) are believed to have osteopenia (T-score ≤ 1.0) in 93 % and osteoporosis (T-score ≤ 2.5) in 38 %. Bone microarchitecture assessed by Trabecular Bone Score (TBS) predicts osteoporotic fractures. Our aim was to evaluate the microarchitecture in adult females with AN by determining TBS and to identify factors potentially associated with TBS, such as bone turnover markers.Methods20 female patients with AN (DSM IV), aged 27.8 ± 4.4 years, BMI 16.6 ± 0.6 kg/m2 and duration of illness of 8.5 ± 5 years had previously been evaluated with dual-energy X-ray absorptiometry (DXA). TBS measurements were now obtained, using iNsight software, from spinal DXA images. Serum levels of bone turnover markers were determined in patients and healthy normal-weight controls.ResultsCompared to controls serum values of osteopontin were higher (p = 0.009). BMD in patients with AN was reduced by at least 1.0 SD at one or more skeletal sites in 65 % of patients and by at least 2.5 SD in 20 %. Only one of the patients (5%) had suffered a fracture. TBS (mean 1.35 ± 0.06; median 1.36 (1.23–1.44) was in the lower normal range (≥ 1.35). 40 % of patients showed partially (> 1.20 and < 1.35) but none showed a fully degraded micro-architecture.ConclusionsIn Swedish AN patients we found a low reduction of BMD and fracture history. The bone microarchitecture, evaluated for the first time for this group by TBS, was only modestly compromised, and to a lesser extent than expected for this group of patients with AN.Level of evidenceLevel V; cross-sectional descriptive study.

The Potential Role of Preoperative Trabecular Bone Score in Predicting Changes in Bone Mineral Density After Parathyroidectomy.

The skeletal indication for parathyroidectomy for primary hyperparathyroidism (PHPT) is based on bone mineral density (BMD) T-score < - 2.5. Whether trabecular bone score (TBS) additionally identifies patients who benefit from parathyroidectomy in terms of bone health is unknown. We aimed to study changes in BMD and TBS among Chinese who underwent curative parathyroidectomy for PHPT, in relation to their preoperative parameters, especially in those with worst site BMD T-score ≥ - 2.5 (non-osteoporotic range). We included consecutive Chinese individuals who underwent curative parathyroidectomy during 2002-2015 for PHPT and completed preoperative and postoperative BMD and TBS measurements in Queen Mary Hospital. Correlations between preoperative parameters and changes in densitometric parameters were studied. 45 Chinese individuals (13 men, 32 women) were included (mean age 62.0 ± 10.0years and BMI 24.6 ± 4.7kg/m2). After parathyroidectomy, BMD at lumbar spine (LS) improved by 6.7% (p < 0.001) while TBS did not change. Among women, peak preoperative parathyroid hormone and calcium levels independently predicted LS BMD gain. Among women with BMD in non-osteoporotic range, LS BMD also improved after parathyroidectomy, where preoperative TBS was the only significant variable inversely correlating with percentage change in LS BMD (ρ - 0.775, p = 0.005). Particularly, those with preoperative TBS ≤ 1.25 gained 7.1% LS BMD post-parathyroidectomy (p = 0.003). LS BMD, but not TBS, improved after parathyroidectomy. Among non-osteoporotic PHPT women, preoperative TBS inversely correlated with postoperative BMD improvement. Hence, low preoperative TBS may be an additional indication for surgical benefit with parathyroidectomy in non-osteoporotic PHPT women, as those with worse preoperative TBS tend to benefit more from surgery.

Associations between bone mineral density, trabecular bone score, and body mass index in postmenopausal females

ObjectivesBone mineral density (BMD), as a gold standard determinant of osteoporosis, assesses only one of many characteristics contributing to the bone. Trabecular bone score (TBS) is applied to evaluate the microarchitecture of trabecular bone. A high body mass index (BMI) has been reported to have a positive correlation with BMD. However, the relation between BMI and TBS has remained unclear. Therefore, the aim of this study is to shed light on the associations between BMI, T-score, and TBS in postmenopausal women without a diagnosed underlying disease. MethodsIn this cross-sectional study, 1054 postmenopausal women were randomly recruited from the Department of Radiology, Isfahan University of Medical Sciences. Demographic characteristics and medical history of all subjects were collected from documents. TBS measurements for L1-L4 vertebrae were retrospectively performed by the TBS iNsight software using the dual X-ray absorptiometry (DXA) from the same region of spine of the subjects. The analysis was done to detect the correlation between TBS and BMI. ResultsA statistically significant negative correlation was found between TBS and BMI in patients with osteoporosis and low bone mass. In patients with normal T-scores, BMI was not significantly correlated to TBS (P > 0.05). Furthermore, there was a significant positive association between T-score and BMI. ConclusionsAlthough a higher BMI had a protective effect against osteoporosis, higher BMI was associated with a lower TBS in patients with an abnormal T-score. However, BMI did not have a significant effect on TBS in patients with normal T-scores.

The assessment of trabecular bone score to improve the sensitivity of FRAX in patients with type 2 diabetes mellitus

Aim. To estimate the trabecular bone score (TBS) for evaluation of fracture probability in order to make decisions about starting osteoporosis treatment in patients with type 2 diabetes mellitus (T2DM).&#x0D; Materials and methods. We obtained the bone mineral density (BMD) and trabecular bone score (TBS) using dual energy X-ray absorptiometry (iDXA) in patients with T2DM (with and without a history of osteoporotic fractures) versus the control group. Before and after TBS measurements we assessed the ten-year probability of fracture using the Fracture Risk Assessment Tool (FRAX).&#x0D; Results. We enrolled 48 patients with T2DM, including 17 with a history of low-traumatic fracture, 31 patients without fractures and 29 subjects of a control group. BMD was higher in patients with T2DM compared to the control group at L1L4 (mean T-score 0.44, 95% CI -3.2 4.9 vs mean T-score 0.33, 95% CI -2.9 3.0 in a control group p=0.052) and Total Hip (mean T-score 0.51, 95% CI -2.1 3.0 vs mean T-score -0.03, 95% CI -1.4 1.2 in a control group p=0,025). The TBS and 10-year probability of fracture (FRAX) was not different in patients with T2DM versus the control group. However, when the TBS was entered as an additional risk factor, the 10-year probability of fracture became higher in patients with T2DM (10-year probability of fracture in T2DM- 8.68, 95% CI 0.3-25.0 versus 6.68, 95% CI 0.415.0 in control group, p=0.04). Among patients with diabetes with and without fractures the FRAX score was higher in subjects with fractures, but no difference was found in regards to BMD or TBS. Entering BMD and TBS values into the FRAX tool in subjects with diabetes and fractures decreased the FRAX score. However, patients with low-traumatic fractures should be treated for osteoporosis without a BMD, TBS or FRAX assessment.&#x0D; Conclusion. TBS improves the results of FRAX assessment in patients with T2DM and should be entered while evaluating FRAX in patients with T2DM. However, additional research is needed to develop a more sensitive tool to evaluate fracture risk in patients with T2DM.

Trabecular bone score may indicate chronic kidney disease-mineral and bone disorder (CKD-MBD) phenotypes in hemodialysis patients: a prospective observational study

BackgroundIn the general population, the trabecular bone score (TBS) represents the bone microarchitecture and predicts fracture risk independent of bone mineral density (BMD). A few studies reported that TBS is significantly reduced in dialysis patients. Chronic kidney disease-mineral and bone disorder (CKD-MBD) are accompanied by increased fracture risk, cardiovascular morbidity, and mortality. We investigated whether TBS is associated with comorbidity related to CKD-MBD or frailty in hemodialysis patients.MethodsIn this prospective observational study, TBS was obtained using the TBS iNsight software program (Med-Imaps) with BMD dual energy x-ray absorptiometry (DXA) images (L1–L4) from prevalent hemodialysis patients. A Tilburg frailty indicator was used to evaluate frailty, and hand grip strength and bio-impedance (InBody) were measured. A patient-generated subjective global assessment (PG-SGA) was used for nutritional assessment. The history of cardiovascular events (CVE) and demographic, clinical, laboratory, and biomarker data were collated. We then followed up patients for the occurrence of CKD-MBD related complications.ResultsWe enrolled 57 patients in total. The mean age was 56.8 ± 15.9 years (50.9% female). Prevalence of Diabetes mellitus (DM) was 40.4% and CVE was 36.8%. Mean TBS was 1.44 ± 0.10. TBS significantly reduced in the CVE group (1.38 ± 0.08 vs. 1.48 ± 0.10, p < 0.001). Multivariable regression analysis was conducted adjusting for age, sex, dialysis vintage, DM, CVE, albumin, intact parathyroid hormone, fibroblast growth factor 23, handgrip strength, and phosphate binder dose. Age (ß = − 0.030; p = 0.001) and CVE (ß = − 0.055; p = 0.024) were significant predictors of TBS. During the follow up period after TBS measurements (about 20 months), four deaths, seven incident fractures, and six new onset CVE were recorded. Lower TBS was associated with mortality (p = 0.049) or new onset fracture (p = 0.007, by log-rank test).ConclusionLower TBS was independently associated with increased age and CVE prevalence in hemodialysis patients. Mortality and fracture incidence were significantly higher in patients with lower TBS values. These findings suggest that TBS may indicate a phenotype of frailty and also a CKD-MBD phenotype reciprocal to CVE.