Older Age and Higher Body Mass Index Are Associated With a More Degraded Trabecular Bone Score Compared to Bone Mineral Density

Trabecular bone score (TBS) may detect subjects with a more degraded microarchitecture but whose bone mineral density (BMD) reflects normal or osteopenia. The purpose of this study was to evaluate whether age and body sizes were associated with the discordance between BMD and TBS. We analyzed BMD and TBS in 1505 Korean women over 40?yr of age who had no history of osteoporotic fractures or conditions that affect bone metabolism. We considered 3 groups to have TBS values that reflected a more degraded TBS than their BMD values: (1) normal BMD but partially degraded TBS, (2) normal BMD but degraded TBS, and (3) osteopenia but degraded TBS. We compared subjects in these 3 groups with other subjects in terms of age and body sizes, and used multivariable logistic regression to analyze the odds ratios (ORs) for the occurrence of a more degraded TBS than their BMD level using age and body mass index (BMI). One hundred sixty subjects (10.6%) were found to have a more degraded TBS than their BMD level; these subjects were older, heavier, and had higher BMIs than the other subjects. Age (OR: 1.038, 95% confidence interval: 1.020–1.057, p <?0.001) and BMI (OR: 1.223, 95% confidence interval: 1.166–1.283, p <?0.001) were statistically significant in the multivariable analysis for the occurrence of this feature. Women with a more degraded TBS than their BMD level are older and have higher BMIs than the other subjects. It may be helpful to consider the possibility of trabecular bone degradation when clinically evaluating fracture risk in patients who are older or who have high BMIs with normal BMD or osteopenia.     

Bone quality assessment in type 2 diabetes mellitus

Summary

The increased risk for fractures in type 2 diabetes mellitus (T2DM) despite higher average bone density is unexplained. This study assessed trabecular bone quality in T2DM using the trabecular bone score (TBS). The salient findings are that TBS is decreased in T2DM and low TBS associates with worse glycemic control.

Introduction

Type 2 diabetes mellitus is a risk factor for osteoporotic fractures despite high average bone mineral density (BMD). The aim of this study was to compare BMD with a noninvasive assessment of trabecular microarchitecture, TBS, in women with T2DM.

Methods

In a cross-sectional study, trabecular microarchitecture was examined in 57 women with T2DM and 43 women without diabetes, ages 30 to 90 years. Lumbar spine BMD was measured by dual-emission x-ray absorptiometry (DXA), and TBS was calculated by examining pixel variations within the DXA images utilizing TBS iNsight software.

Results

Mean TBS was lower in T2DM (1.228?±?0.140 vs. 1.298?±?0.132, p?=?0.013), irrespective of age. Mean BMD was higher in T2DM (1.150?±?0.172 vs. 1.051?±?0.125, p?=?0.001). Within the T2DM group, TBS was higher (1.254?±?0.148) in subjects with good glycemic control (A1c?≤?7.5 %) compared to those (1.166?±?0.094; p?=?0.01) with poor glycemic control (A1c?>?7.5 %).

Conclusion

In T2DM, TBS is lower and associated with poor glycemic control. Abnormal trabecular microarchitecture may help explain the paradox of increased fractures at a higher BMD in T2DM. Further studies are needed to better understand the relationship between glycemic control and trabecular bone quality.     

Bone quality, as measured by trabecular bone score in patients with adrenal incidentalomas with and without subclinical hypercortisolism

Patients with adrenal incidentalomas (AIs) and subclinical hypercortisolism (SH) have increased risk of fracture independent of bone mineral density (BMD) and possibly due to reduced bone quality. The trabecular bone score (TBS) has been proposed as a index of bone microarchitecture. The aim of the study was to investigate TBS in AI. In 102 AI patients, SH was diagnosed in the presence of at least two of the following: (1) urinary free cortisol >70 µg/24 h (193.1 nmol/L); (2) cortisol after 1‐mg dexamethasone suppression test (1‐mg DST) >3.0 µg/dL (82.8 nmol/L); or (3) adrenocorticotropic hormone (ACTH) <10 pg/mL (<2.2 pmol/L). In patients and in 70 matched controls, BMD was measured at lumbar spine (LS) and femur (neck [FN] and total [FT]) by dual X‐ray absorptiometry and TBS was assessed in the region of LS‐BMD; BMD and TBS data were reported as Z‐scores. In patients, vertebral deformities were assessed by radiograph. Patients with SH (n = 34) had lower LS‐BMD (?0.31 ± 1.17), FT‐BMD (?0.29 ± 0.91), and TBS (?3.18 ± 1.21) than patients without SH (n = 68, 0.31 ± 1.42, p = 0.03; 0.19 ± 0.97, p = 0.01; ?1.70 ± 1.54, p < 0.0001, respectively) and controls (0.42 ± 1.52, p = 0.02; 0.14 ± 0.76, p = 0.02; ?1.19 ± 0.99, p < 0.0001, respectively). TBS was inversely correlated with 1‐mg DST (β = ?0.26, t = ?2.79, p = 0.006) regardless of age, LS‐BMD, body mass index (BMI), and gender. The presence of fracture was associated with low TBS alone (odds ratio [OR], 4.8; 95% confidence interval [CI], 1.85–12.42, p = 0.001) and with the cluster low TBS plus low LS‐BMD (OR, 4.37; 95% CI, 1.71–11.4, p = 0.002), after adjustment for age, BMI, and gender. Low TBS plus low LS‐BMD showed a good specificity (79%) for predicting fractures, whereas normal TBS (ie, > ?1.5) plus normal LS‐BMD high specificity (88.1%) for excluding fractures. Finally, TBS predicted the occurrence of a new fracture in 40 patients followed for 24 months (OR, 11.2; 95%CI, 1.71–71.41, p = 0.012) regardless of LS‐BMD, BMI, and age. In SH, bone quality, as measured by TBS, is altered. TBS is useful in detecting AI patients at risk of fractures. © 2012 American Society for Bone and Mineral Research.     

Lower Trabecular Bone Score is Associated With the Use of Proton Pump Inhibitors

Introduction: Trabecular bone score (TBS) provides indirect indices of trabecular microarchitecture and bone quality. Several studies have evaluated the influence of proton pump inhibitors (PPIs) on bone mass and geometric parameters, but no studies have evaluated the influence of PPIs on TBS. Methods: We reviewed the medical records of 1505 women aged 40–89 yr who had bone mineral density (BMD) examinations as a part of the medical diagnosis and disease prevention program and who did not have osteoporotic fractures or conditions that could affect bone metabolism. Among these, we identified 223 women with exposure to PPIs and selected the same number of age- and body mass index (BMI)-matched control patients. We compared TBS and BMD between the PPI exposure group and the control group and performed multivariate regression analyses to determine whether TBS and BMDs are associated with age, BMI, and PPIs exposure. We also examined whether TBS and BMDs are associated with PPIs exposure timing (current, recent, and past). Results: TBS and BMDs were significantly lower in the PPI exposure group than in the control group. In a multivariable linear regression analysis, TBS was significantly associated with age (p < 0.001) and PPI exposure (p = 0.02). In addition, all BMDs were found to be significantly associated with age, BMI, and PPI exposure. Lower TBS was associated with current PPIs use (p = 0.005), but not with recent or past PPIs usage. However, the influence of PPI exposure timing on the BMDs was not consistent between BMD measurement sites. Conclusions: This study found that TBS is lower in subjects with PPIs exposure than in controls. The association of lower TBS with current PPIs use suggests that trabecular bone quality could be affected early by PPIs, and but the effect might be reversible.     

Muscular Maximal Strength Indices and Bone Variables in a Group of Elderly Women

The aim of the present study was to explore the relations between muscular maximal strength indices and bone parameters (bone mineral density [BMD], hip geometry indices, and trabecular bone score [TBS]) in a group of elderly women. This study included 35 healthy elderly women whose ages range between 65 and 75 yr (68.1 ± 3.1 yr). BMD (in gram per square centimeter) was determined for each individual by dual-energy X-ray absorptiometry at the whole body, lumbar spine (L1–L4), total hip (TH), and femoral neck (FN). L1–L4 TBS and hip geometry indices were also evaluated by dual-energy X-ray absorptiometry. Maximal muscle strength of bench press (1-repetition maximum [RM] bench press), maximal muscle strength of leg press (1-RM leg press), and handgrip were measured using validated methods. 1-RM bench press was positively correlated to TH BMD (r = 0.40; p < 0.05), FN BMD (r = 0.41; p < 0.05), FN section modulus (r = 0.33; p < 0.05), and FN cross-sectional moment of inertia (r = 0.35; p < 0.05). 1-RM leg press was positively correlated to TH BMD (r = 0.50; p < 0.01), FN BMD (r = 0.35; p < 0.05), FN cross-sectional area (r = 0.38; p < 0.05), and TBS (r = 0.37; p < 0.05). Handgrip was correlated only to FN cross-sectional moment of inertia (r = 0.43; p < 0.01). This study suggests that 1-RM bench press and 1-RM leg press are positive determinants of BMD in elderly women.     

Usefulness of Trabecular Bone Score (TBS) to Identify Bone Fragility in Patients with Primary Hyperparathyroidism

Background: Patients with primary hyperparathyroidism usually show decreased bone strength that are often not well diagnosed by conventional Dual-energy X-ray absorptiometry (DXA). Trabecular Bone Score (TBS) is a new technique for assessing bone microarchitecture indirectly. This cross-sectional study evaluates the usefulness of TBS in patients with primary hyperparathyroidism in clinical practice. Methodology: Bone mineral density (BMD) by DXA and TBS values by TBS InSight® software were determined in 72 patients with primary hyperparathyroidism to analyze its relationship with fragility fractures. A receiver operating curve was performed to evaluate the usefulness of TBS as predictor of fragility fractures. FRAX index with and without adjustment by TBS was calculated. Additionally, longitudinal data of a subgroup of patients according to the therapeutic management were also evaluated. Results: A total of 51.4% of the patients showed degraded microarchitecture while only 37.5% of them were diagnosed of osteoporosis by DXA. No significant correlation was found between TBS values and BMD parameters. However, TBS values were lower in osteoporotic patients compared to those classified as normal by BMD (1.16 ± 0.12vs 1.26 ± 0.17; p?=?0.043) and in patients with fragility fractures compared to nonfractured patients (1.19 ± 0.03vs 1.24 ± 0.02, p < 0.001). The area under the curve for TBS performed better than the combination of femoral, hip and spine-BMD for prevalent fractures (0.714vs 0.679). TBS-adjusted FRAX was higher than nonadjusted model for both major osteoporotic and hip fracture (4.5% vs 3%; 0.9% vs 0.7%; p < 0.001). At follow-up, an improvement in TBS values was observed in treated patients (medical or surgical) vs nontreated close to significance (1.27 ± 0.10vs 1.24 ± 0.11, p?=?0.074). Conclusions: TBS could be a useful tool to identify increased fracture risk in patients with primary hyperparathyroidism underdiagnosed by BMD. Moreover, FRAX adjusted by TBS could be a more robust tool for predicting the risk of osteoporotic fracture to help in therapeutic decisions in this population.     

Spine Trabecular Bone Score Subsequent to Bone Mineral Density Improves Fracture Discrimination in Women

Bone mineral density (BMD) measured by dual-energy X-ray absorptiometry (DXA) is used to diagnose osteoporosis and assess fracture risk. However, DXA cannot evaluate trabecular microarchitecture. This study used a novel software program (TBS iNsight; Med-Imaps, Geneva, Switzerland) to estimate bone texture (trabecular bone score [TBS]) from standard spine DXA images. We hypothesized that TBS assessment would differentiate women with low trauma fracture from those without. In this study, TBS was performed blinded to fracture status on existing research DXA lumbar spine (LS) images from 429 women. Mean participant age was 71.3 yr, and 158 had prior fractures. The correlation between LS BMD and TBS was low (r = 0.28), suggesting these parameters reflect different bone properties. Age- and body mass index–adjusted odds ratios (ORs) ranged from 1.36 to 1.63 for LS or hip BMD in discriminating women with low trauma nonvertebral and vertebral fractures. TBS demonstrated ORs from 2.46 to 2.49 for these respective fractures; these remained significant after lowest BMD T-score adjustment (OR = 2.38 and 2.44). Seventy-three percent of all fractures occurred in women without osteoporosis (BMD T-score > −2.5); 72% of these women had a TBS score below the median, thereby appropriately classified them as being at increased risk. In conclusion, TBS assessment enhances DXA by evaluating trabecular pattern and identifying individuals with vertebral or low trauma fracture. TBS identifies 66–70% of women with fracture who were not classified with osteoporosis by BMD alone.     

Lumbar Spine Trabecular Bone Score (TBS) Reflects Diminished Bone Quality in Patients With Diabetes Mellitus and Oral Glucocorticoid Therapy

Trabecular bone score (TBS) is a texture parameter that measures the grayscale variation within dual-energy X-ray absorptiometry (DXA) images, and has been shown to significantly correlate with the 3-dimensional bone microarchitecture. The objective of this study was to determine whether TBS is a better clinical tool than traditionally used bone mineral density (BMD) to detect the skeletal deterioration seen in patients with diabetes (DM), patients undergoing oral glucocorticoid (GC) therapy, and patients who are both diabetic and taking steroids (GC?+?DM). We performed retrospective, cross-sectional study using DXA images of patients who visited UTHealth Department of Internal Medicine DXA clinic in Houston, TX, from May 30, 2014 to May 30, 2016. A total of 477 men and women, who were 55 years or older, were included in the study. Lumbar spine (LS) BMD and TBS were collected. Electronic medical records were reviewed to collect clinical information for each patient. When both men and women were analyzed as a single group, LS-BMD was significantly higher in the diabetic group than in the control group (1.14 vs 1.10, p?=?0.038), whereas mean TBS of L1–L4 was significantly lower in the diabetic group (1.21 vs 1.26, p?=?0.004). LS-TBS was also significantly lower in diabetic women than in nondiabetic women (1.20 vs 1.26, p?=?0.002). Receiver operating characteristic curves and areas under the curve indicated that LS-TBS provided better ability than LS-BMD to discriminate between control subjects and those in the DM, GC, or GC?+?DM groups (areas under the curve between 0.645 and 0.697, p?<?0.010 for all). LS-TBS is a BMD-independent parameter that is capable of capturing a larger portion of bone quality deterioration undetected by BMD alone in patients with DM and undergoing oral GC therapy.     

Trabecular Bone Score in Children and Adolescents With Inflammatory Bowel Diseases

Introduction: Trabecular bone score (TBS) is a textural index that evaluates bone microarchitecture of the lumbar spine. Our aim was to assess TBS in children with inflammatory bowel diseases and to evaluate correlations with clinical, laboratory and densitometric variables. Methods: A retrospective study of TBS and areal bone mineral density measurements by dual-energy X-ray absorptiometry (DXA) of children with either Crohn's disease (CD) or ulcerative colitis (UC). Bone mineral apparent density was calculated for size adjustment. TBS Z-score for each child were calculated based on data from a healthy population of similar age and gender distribution. Variables significantly associated with TBS were included in stepwise linear regression models to examine independent predictors of TBS. Results: Fifty patients (age at DXA scan 13.8 ± 3.0 years, 29 males) were included. No significant differences were observed between the patients with CD and UC, in age at diagnosis, age at DXA scan and disease duration. The mean TBS of patients with CD (n = 35) was lower than of patients with UC (n = 15): 1.340 ± 0.080 vs 1.395 ± 0.092, p = 0.040. The mean TBS Z-score of patients with CD, ?0.443 ± 0.788, was significantly lower than expected in healthy children (p = 0.002), while the mean TBS Z-score of patients with UC, 0.231 ± 0.685, was similar to that of healthy children (p = 0.212). In the stepwise linear regression analysis, BMI Z-score at diagnosis, phosphorus level at diagnosis and age at the time of the DXA scan were significant independent predictors of TBS (r² = 0.604; β = 0.037, 95% confidence interval (CI) for β 0.022–0.051, p < 0.001; β = 0.045, 95% CI: 0.017–0.073, p = 0.002; and β = 0.031, 95% CI: 0.005–0.021, p < 0.002, respectively). Conclusions: TBS is significantly reduced in pediatric patients with CD but not in patients with UC. This finding likely reflects the effect of CD on bone microarchitecture.     

Bone status in glucocorticoid-treated men and women

Summary

We recorded the results of areal bone mineral density (aBMD) and microarchitecture of the bone measured by trabecular bone score (TBS) in 416 glucocorticoid-treated men and women aged 40 years and older with or without fracture to 1104 controls. TBS better discriminated those with fracture compared to aBMD. These differences were the greatest in men.

Introduction

The aim of this study is to evaluate glucocorticoid (GC)-induced effects on areal bone mineral density (aBMD) and bone microarchitectural texture measured by trabecular bone score (TBS).

Methods

TBS and aBMD were evaluated at L1–L4 postero-anterior (PA) spine by dual X-ray absorptiometry (DXA) in 1520 men and women aged 40 years and over. Four hundred sixteen subjects who received GCs (≥5 mg/day, for ≥3 months) were matched with 1104 sex-, age-, and BMI-matched control subjects. Clinical data, osteoporotic fractures (OPF), and dietary habits were documented in the medical report.

Results

GC-treated patients were characterized by a significant decrease of TBS (1.267 vs. 1.298, p?<?0.001) compared with control-matched subjects while no change in BMD was observed at any sites. These decreases were even more pronounced when fracture status was taken into account (1.222 vs. 1.298, p?<?0.001). The odds ratio (OR) for TBS was 1.44 (1.095–1.89) for OPF, whereas no association was found for BMD at any sites (all p?>?0.3). A similar effect on microarchitecture measured by TBS was seen by the presence of fracture as by the use of glucocorticoids. An influence on TBS by sex was also noted with a decrease in TBS of greater magnitude in men.

Conclusions

GC-treated individuals have a significant deterioration of bone microarchitectural texture as assessed by TBS which is more marked in those with OPF and in men. TBS seems to be more sensitive than aBMD for GC-related fracture detection and should be a good surrogate indicator of bone health in such secondary osteoporosis.

     

Bone Microarchitecture Assessed by Trabecular Bone Score Is Independent of Mobility Level or Height in Pediatric Patients with Cerebral Palsy

Bone strength and fracture risk do not only depend on bone density, but also on bone structure. The trabecular bone score (TBS) evaluates homogeneity of bone microarchitecture indirectly by measuring gray-level variations of two-dimensional (2D) DXA images. Although TBS is well-established for adults, there have been only few publications in pediatrics. In this monocentric retrospective analysis, we investigated TBS in children and adolescents with cerebral palsy (CP), a patient group vulnerable to low bone mineral mass due to impaired mobility. The influence of different parameters on TBS and areal BMD (aBMD) were evaluated, as well as the relationship between TBS and aBMD. We compared TBS values of our study population to a reference population. A total of 472 lumbar spine–dual-energy X-ray absorptiometry (LS-DXA) scans of children and adolescents with CP (205 female), aged between 4 and 18 years, were analyzed. The DXA-scans were part of the routine examination. The children had no records of fractures or specific bone diseases. Our study population with CP had similar TBS as the reference population. TBS did not increase with age until an inflection point at 10 years in females, and 12 years in males. Girls had significantly higher TBS than boys (p = .049) and pubertal girls aged 8 to 13 years had significantly higher TBS than prepubertal girls (p = .009). TBS standard deviation score for age (SDS-TBS) and aBMD Z-scores correlated weakly (p < .001; R = 0.276 [males], R = 0.284 [females]). Other than for aBMD Z-scores, SDS-TBS was not influenced by age-adjusted height Z-scores and there was no significant difference in SDS-TBS when grouped by mobility levels, using the Gross Motor Function Classification System (GMFCS). Our results indicate that children with CP have a similar homogeneous distribution of trabecular microarchitecture as controls. Puberty initiation appears to be essential for increase of TBS with age and for sex differences. TBS seems less influenced by body composition, height, and mobility than aBMD. © 2020 The Authors. Journal of Bone and Mineral Research published by American Society for Bone and Mineral Research.     

Trabecular Bone Score (TBS) Predicts Fracture in Ankylosing Spondylitis: The Manitoba BMD Registry

Introduction: Ankylosing spondylitis (AS) is a chronic inflammatory disease of the spine characterized among other features by spinal boney proliferation, back pain, loss of flexibility, and increased fracture risk. Overlying bone limits the utility of bone mineral density (BMD) by dual X-ray absorptiometry (DXA) in the spine. Trabecular bone score (TBS) is a bone texture measurement derived from the spine DXA image that indicates bone quality and fracture risk independent of BMD. Methodology: Using the Manitoba Bone Density Program database, patients with diagnosis codes for ankylosing spondylitis, baseline DXA and lumbar spine TBS were identified. Incident nontraumatic fractures (major osteoporotic [MOF], clinical spine, hip, and all fracture) were identified from population based databases. Cox-proportional hazard models are presented. Results: We identified 188 patients with diagnosed AS. TBS was lower in those with incident MOF (1.278 ± 0.126, compared to 1.178 ± 0.136, p < 0.001). Unadjusted TBS and FRAX-MOF-BMD adjusted predicted major osteoporotic fracture (N = 19) (hazard ratio [HR] 2.04, 95% confidence interval [CI]: 1.28–2.26, p = 0.003; HR 1.81, 95% CI: 1.11–2.96, p = 0.018). TBS unadjusted and FRAX-MOF-BMD adjusted also predicted clinical spine fracture (N = 7) (HR 2.50, 95% CI: 1.17–5.37; p = 0.019; HR 2.40 95% CI: 1.1–5.25; p = 0.028). Higher HRs were observed for prediction of hip fracture (N = 6), but these did not achieve statistical significance (FRAX-adjusted HR 1.74, 95% 0.73–4.17; p = 0.211). Unadjusted models show TBS was predictive of all fracture (N = 27) (HR 1.60, 95% CI: 1.08–2.39; p = 0.020), which was borderline significant after adjustment for FRAX-MOF-BMD (HR 1.51, 95% CI: 1.00–2.29; p = 0.052). Conclusion: We report the first analysis of TBS for fracture prediction as an incident event in AS. TBS independently predicted major osteoporotic and clinical spine fracture in AS independent of FRAX.     

Comparative effects of teriparatide and ibandronate on spine bone mineral density (BMD) and microarchitecture (TBS) in postmenopausal women with osteoporosis: a 2-year open-label study

Summary

Treatment effects over 2 years of teriparatide vs. ibandronate in postmenopausal women with osteoporosis were compared using lumbar spine bone mineral density (BMD) and trabecular bone score (TBS). Teriparatide induced larger increases in BMD and TBS compared to ibandronate, suggesting a more pronounced effect on bone microarchitecture of the bone anabolic drug.

Introduction

The trabecular bone score (TBS) is an index of bone microarchitecture, independent of bone mineral density (BMD), calculated from anteroposterior spine dual X-ray absorptiometry (DXA) scans. The potential role of TBS for monitoring treatment response with bone-active substances is not established. The aim of this study was to compare the effects of recombinant human 1–34 parathyroid hormone (teriparatide) and the bisphosphonate ibandronate (IBN), on lumbar spine (LS) BMD and TBS in postmenopausal women with osteoporosis.

Methods

Two patient groups with matched age, body mass index (BMI), and baseline LS BMD, treated with either daily subcutaneous teriparatide (N?=?65) or quarterly intravenous IBN (N?=?122) during 2 years and with available LS BMD measurements at baseline and 2 years after treatment initiation were compared.

Results

Baseline characteristics (overall mean ± SD) were similar between groups in terms of age 67.9?±?7.4 years, body mass index 23.8?±?3.8 kg/m², BMD L1–L4 0.741?±?0.100 g/cm², and TBS 1.208?±?0.100. Over 24 months, teriparatide induced a significantly larger increase in LS BMD and TBS than IBN (+7.6 %?±?6.3 vs. +2.9 %?±?3.3 and +4.3 %?±?6.6 vs. +0.3 %?±?4.1, respectively; P?<?0.0001 for both). LS BMD and TBS were only weakly correlated at baseline (r ²?=?0.04) with no correlation between the changes in BMD and TBS over 24 months.

Conclusions

In postmenopausal women with osteoporosis, a 2-year treatment with teriparatide led to a significantly larger increase in LS BMD and TBS than IBN, suggesting that teriparatide had more pronounced effects on bone microarchitecture than IBN.     

Bone microarchitecture assessed by TBS predicts osteoporotic fractures independent of bone density: the Manitoba study

The measurement of BMD by dual‐energy X‐ray absorptiometry (DXA) is the “gold standard” for diagnosing osteoporosis but does not directly reflect deterioration in bone microarchitecture. The trabecular bone score (TBS), a novel gray‐level texture measurement that can be extracted from DXA images, correlates with 3D parameters of bone microarchitecture. Our aim was to evaluate the ability of lumbar spine TBS to predict future clinical osteoporotic fractures. A total of 29,407 women 50 years of age or older at the time of baseline hip and spine DXA were identified from a database containing all clinical results for the Province of Manitoba, Canada. Health service records were assessed for the incidence of nontraumatic osteoporotic fracture codes subsequent to BMD testing (mean follow‐up 4.7 years). Lumbar spine TBS was derived for each spine DXA examination blinded to clinical parameters and outcomes. Osteoporotic fractures were identified in 1668 (5.7%) women, including 439 (1.5%) spine and 293 (1.0%) hip fractures. Significantly lower spine TBS and BMD were identified in women with major osteoporotic, spine, and hip fractures (all p < 0.0001). Spine TBS and BMD predicted fractures equally well, and the combination was superior to either measurement alone (p < 0.001). Spine TBS predicts osteoporotic fractures and provides information that is independent of spine and hip BMD. Combining the TBS trabecular texture index with BMD incrementally improves fracture prediction in postmenopausal women. © 2011 American Society for Bone and Mineral Research     

The predictive value of trabecular bone score (TBS) on whole lumbar vertebrae mechanics: an ex vivo study

Summary

We investigated the association of trabecular bone score (TBS) with microarchitecture and mechanical behavior of human lumbar vertebrae. We found that TBS reflects vertebral trabecular microarchitecture and is an independent predictor of vertebral mechanics. However, the addition of TBS to areal BMD (aBMD) did not significantly improve prediction of vertebral strength.

Introduction

The trabecular bone score (TBS) is a gray-level measure of texture using a modified experimental variogram which can be extracted from dual-energy X-ray absorptiometry (DXA) images. The current study aimed to confirm whether TBS is associated with trabecular microarchitecture and mechanics of human lumbar vertebrae, and if its combination with BMD improves prediction of fracture risk.

Methods

Lumbar vertebrae (L3) were harvested fresh from 16 donors. The anteroposterior and lateral bone mineral content (BMC) and areal BMD (aBMD) of the vertebral body were measured using DXA; then, the TBS was extracted using TBS iNsight software (Medimaps SA, France). The trabecular bone volume (Tb.BV/tissue volume, TV), trabecular thickness (Tb.Th), degree of anisotropy, and structure model index (SMI) were measured using microcomputed tomography. Quasi-static uniaxial compressive testing was performed on L3 vertebral bodies to assess failure load and stiffness.

Results

The TBS was significantly correlated to Tb.BV/TV and SMI (r?=?0.58 and ?0.62; p?=?0.02, 0.01), but not related to BMC and BMD. TBS was significantly correlated with stiffness (r?=?0.64; p?=?0.007), independently of bone mass. Using stepwise multiple regression models, we failed to demonstrate that the combination of BMD and TBS was better at explaining mechanical behavior than either variable alone. However, the combination TBS, Tb.Th, and BMC did perform better than each parameter alone, explaining 79 % of the variability in stiffness.

Conclusions

In our study, TBS was associated with microarchitecture parameters and with vertebral mechanical behavior, but TBS did not improve prediction of vertebral biomechanical properties in addition to aBMD.     

Bone Impairment in a Large Cohort of Chinese Patients With Tumor-Induced Osteomalacia Assessed by HR-pQCT and TBS

Tumor-induced osteomalacia (TIO) is a rare paraneoplastic syndrome caused by excessive production of fibroblast growth factor 23 (FGF23) by a tumor. Previous studies have revealed generalized mineralization defects and low areal bone mineral density (aBMD) in TIO. However, data on the bone microarchitecture in TIO are limited. In this study, we evaluated the microarchitecture in the peripheral (distal radius and tibia) and axial (lumbar spine) skeleton using high-resolution peripheral quantitative computed tomography (HR-pQCT) and trabecular bone score (TBS) and investigated related factors in a large cohort of Chinese patients with TIO. A total of 186 patients with TIO who had undergone dual-energy X-ray absorptiometry (DXA) or HR-pQCT scans were enrolled. Compared with age-, sex-, and body mass index (BMI)-matched healthy controls, TIO patients (n = 113) had lower volumetric BMD, damaged microstructure, and reduced bone strength in the peripheral skeleton, especially at the tibia. The average TBS obtained from 173 patients was 1.15 ± 0.16. The proportion of patients with abnormal TBS (<1.35) was higher than that with low L₁ to L₄ aBMD Z-score (Z ≤ −2) (43.9% versus 89.6%, p < 0.001). Higher intact fibroblast growth factor 23 (iFGF23), intact parathyroid hormone (iPTH), alkaline phosphatase, and β-isomerized C-terminal telopeptide of type I collagen (β-CTx) levels, more severe mobility impairment, and a history of fracture were associated with poorer HR-pQCT parameters but not with lower TBS. However, greater height loss and longer disease duration were correlated with worse HR-pQCT parameters and TBS. Moreover, TBS was correlated with both trabecular and cortical HR-pQCT parameters in TIO. In conclusion, we revealed impaired bone microarchitecture in the axial and peripheral skeleton in a large cohort of Chinese TIO patients. HR-pQCT parameters and TBS showed promising advantages over aBMD for assessing bone impairment in patients with TIO. A longer follow-up period is needed to observe changes in bone microarchitecture after tumor resection. © 2021 American Society for Bone and Mineral Research (ASBMR).     

Chronic hemodialysis is associated with lower trabecular bone score,independent of bone mineral density: a case-control study

Summary

We measured trabecular bone score (TBS) in 98 patients on permanent hemodialysis (HD) and 98 subjects with similar bone mineral density and normal kidney function. TBS was significantly lower in HD patients, indicating deteriorated bone microarchitecture, independent of bone mass. This might partially explain the increased fracture risk in HD.

Purpose

In the general population, trabecular bone score (TBS) was shown to predict fracture independent of bone mineral density (BMD). In end-stage renal disease patients on hemodialysis (HD), the value of TBS is beyond that of BMD in currently unclear. Our aim was to assess lumbar spine (LS) TBS in HD patients compared with subjects with normal kidney function matched for age, sex, and LS BMD.

Methods

We assessed TBS and LS and femoral neck (FN) BMD in 98 patient on permanent HD (42.8% males; mean age 57.5?±?11.3 years; dialysis vintage 5.5?±?3.8 years) and 98 control subjects (glomerular filtration rate?>?60 mL/min) using DXA. We simultaneously controlled for sex, age (±?3 years), and LS BMD (±?0.03 g/cm²).

Results

HD patients had significantly lower LS TBS (0.07 [95% CI 0.03–0.1]; p?=?0.0004), TBS T-score (0.83 SD [95% CI 0.42–1.24]; p?=?0.0001)) and TBS Z-score (0.81 SD [95% CI 0.41–1.20]; p?=?0.0001) than matched controls. TBS significantly correlated with LS BMD in both HD patients (r?=?0.382; p?=?0.001) and controls (r?=?0.36; p?=?0.002). The two regression lines had similar slopes (0.3 vs. 0.28; p?=?0.84) with different intercepts (0.88 vs. 0.98). TBS adjustment significantly increased the 10-year fracture risk from 3.7 to 5.3 for major osteoporotic fracture and from 0.9 to 1.5 for hip fracture.

Conclusions

HD patients have lower TBS than controls matched for LS BMD, indicating altered bone microarchitecture. Also, the magnitude of TBS reduction in HD patients is constant at any LS BMD. Adjustment for TBS partially corrects the absolute 10-year fracture risk.

     

Trabecular Bone Score Is a Useful Parameter for the Prediction of Vertebral Fractures in Patients With Polymyalgia Rheumatica

Introduction: Polymyalgia rheumatica (PMR), a benign rheumatic disorder, requires long-term glucocorticoid therapy, which could be associated with osteoporosis. In the present study, we compared bone mineral density (BMD), trabecular bone score (TBS) and frequencies of vertebral fracture (VF) among patients with PMR or rheumatoid arthritis (RA) and controls. Methods: Fifty-three postmenopausal women with PMR aged 50 yr or older were eligible for inclusion in this study. Subjects in RA (n = 106) and control (n = 106) groups were selected by propensity score matching with controlling age, body mass index and use of anti-osteoporotic agents. Results: The frequency of VF in patients with PMR (30.2%) was significantly higher than those in patients with RA (13.2 %) and controls (13.2%, p = 0.017). The mean TBS of patients with PMR (1.317 ± 0.092) was significantly lower than those of patients with RA (1.336 ± 0.089) and the controls (1.373 ± 0.073, p < 0.001). In receiver operating characteristic analysis for VF in patients with PMR, the area under the curve (AUC) was 0.759 (95% confidence interval [CI] = 0.601–0.918, p < 0.001) for TBS and 0.618 (95% CI = 0.442–0.795, p < 0.001) for L-spine BMD. The AUCs were 0.760 (95% CI = 0.630–0.891, p ≤ 0.001) and 0.767 (95% CI 0.627–0.907, p < 0.001) for femur neck and total hip BMD, respectively. Multivariate analysis identified the factor associated with VF of patients with PMR as a lower TBS (Odds ratio: 0.000, 95% CI: 0.000, 0.754, p = 0.043). Conclusion: TBS could be a supplementary tool for discriminating osteoporotic fractures in postmenopausal patients with PMR.     

Fat Mass Does Not Increase the Precision Error of Trabecular Bone Score Measurements

Introduction: Trabecular bone score (TBS) is an indirect index of trabecular microarchitecture derived from lumbar spine dual-energy X-ray absorptiometry. Previous phantom study showed that an increase in soft tissue thickness does not affect TBS reproducibility. We investigated the effect of increasing body mass index (BMI) and waist circumference on TBS precision error on patients, compared to bone mineral density (BMD). Methodology: A population of postmenopausal Caucasian women was distributed in 3 different BMI (normal, overweight, and class I obesity), plus 2 further groups based on waist circumference diameter (≤88 cm and >88 cm, respectively). In vivo precision error was calculated on 30 consecutive subjects that were scanned 2 times, with patient repositioning, using the Hologic QDR-Discovery W densitometer. Coefficient of variation, percent least significant change, and reproducibility were calculated according to the International Society for Clinical Densitometry guidelines. Results: Ninety-five women aged 66 ± 10 (mean ± standard deviation) were included. No significant differences were found both for BMD and TBS precision errors, respectively, when comparing BMI groups and waist circumference groups. BMD reproducibility ranged from 95.9% (BMI > 30 kg/m²) to 97.5% (BMI < 25 kg/m²). TBS reproducibility ranged between 95.8% (BMI = 25–29.9 kg/m², waist circumference > 88 cm) and 96.6% (BMI < 25 kg/m²). With the exception of obese group, a significant difference was found between BMD and TBS reproducibility, being that of TBS slightly lower than BMD. A significant decrease of TBS values was found between normal and obese subjects, as well as between waist circumference groups. Conclusions: TBS precision error is not affected by BMI and waist circumference differences. TBS reproducibility showed to be slightly lower than that of BMD, but this difference was mitigated in obese patients. A negative association was found between the amount of fat mass and TBS mean values.