Trabecular Bone Mineral Density Research Articles

Effects of Abaloparatide on Bone Mineral Density in Proximal Femoral Regions Corresponding to Arthroplasty Gruen Zones: A Study of Postmenopausal Women with Osteoporosis.

Low hip bone mineral density (BMD) in patients who undergo total hip arthroplasty (THA) increases the risk of periprosthetic fractures, implant instability, and other complications. Recently, emphasis has been placed on bone health optimization: treating low BMD prior to a planned orthopaedic implant procedure in an effort to normalize BMD and reduce the potential risk of future complications. Abaloparatide is a U.S. Food and Drug Administration-approved osteoanabolic agent for men and postmenopausal women with osteoporosis and a candidate drug for bone health optimization that, in addition to benefits at the spine, increases hip BMD and reduces nonvertebral fracture risk. We hypothesized that abaloparatide would improve BMD in proximal femoral regions surrounding a virtual THA stem. This post hoc analysis obtained dual x-ray absorptiometry (DXA) hip scans from 500 randomly selected postmenopausal women with osteoporosis from the Phase-3 Abaloparatide Comparator Trial in Vertebral Endpoints (ACTIVE, NCT01343004) study after 0, 6, and 18 months of abaloparatide (250 patients) or placebo (250 patients). Hip DXA scans underwent 3-dimensional (3D) modeling via 3D-Shaper, followed by virtual resection of the proximal femur and simulated placement of a tapered, flat-wedge hip stem that guided delineation of the Gruen zones that were fully (zones 1 and 7) or largely (zones 2 and 6) captured in the scanning region. Integral, cortical, and trabecular volumetric BMD, cortical thickness, and cortical surface BMD (the product of cortical volumetric BMD and cortical thickness) were determined for each zone. Compared with placebo, the abaloparatide group showed greater increases in integral volumetric BMD in all zones at months 6 and 18; cortical surface BMD in zones 1, 6, and 7 at month 6; cortical thickness, cortical volumetric BMD, and cortical surface BMD in all zones at month 18; and trabecular volumetric BMD in zones 1 and 7 at months 6 and 18. Abaloparatide increases BMD in proximal femoral regions that interact with and support femoral stems, suggesting that abaloparatide may have value for preoperative or potentially perioperative bone health optimization in patients with osteoporosis undergoing THA. Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Increase in lumbar spine but not distal radius bone mineral density in adults after pancreas kidney transplantation

Osteoporosis occurs in every third individual after simultaneous pancreas kidney transplantation (SPKT). Currently used bone measures insufficiently predict their fracture risk. Lumbar spine Trabecular bone score (TBS) and distal radius areal and volumetric bone mineral density (BMD) were monitored for the first time in patients with type 1 diabetes and chronic renal failure after SPKT with steroid-sparing protocol. In 33 subjects (mean age 43.4 ± 9.8 years), dual-energy X-ray absorptiometry and peripheral quantitative computed tomography were performed just after SPKT (baseline) and one and three years later. While TBS Z-scores increased (−1.1 ± 1.2 and −0.3 ± 1.0; p˂0.001, at baseline and year three, respectively), trabecular volumetric BMD Z-scores at distal radius metaphysis did not change during the study (−1.3 ± 1.3 and −1.3 ± 1.0; p = 0.38). Similarly, areal BMD Z-scores increased at lumbar spine, total hip and femoral neck (all p < 0.01), but not at the distal radius. SPKT induced bone measures' improvement at lumbar spine and hip but not at distal radius. Before suggesting changes in current clinical care, predictive value of individual bone measures or its combination for fracture risk assessment remains to be elucidated.

Evaluation of Trabecular Bone Microarchitecture and Bone Mineral Density in Young Women, Including Selected Hormonal Parameters.

The absence of non-invasive methods for assessing bone material and structural changes is a significant diagnostic challenge. Dual-energy X-ray absorptiometry (DXA) bone mineral density (BMD) testing is the gold standard for osteoporosis diagnosis. BMD and the trabecular bone score (TBS) have facilitated targeted osteoporosis prevention and treatment in clinical settings. The findings from this study indicate that BMD modulation in young women is influenced by various hormones, potentially compromising the diagnostic precision of BMD for subclinical bone demineralization. A total of 205 women aged 19 to 37 underwent anthropometric measurements and hormonal tests. BMD was determined using DXA, and TBS values were computed from the lumbar spine L1-L4 segment. The multivariate analysis findings suggest that BMD might not be determined by hormones. The relationship between TBS and TSH was statistically significant in the univariate analysis, which indicates the efficacy of further studies to determine the link between TBS and specific hormones. Analyzing the strength of the correlation between TBS and hormones in the univariate analysis shows which factors are worth considering in further analyses. This makes it possible to create better techniques that will help identify young women who are at a higher risk of developing osteoporosis.

Comparison of the therapeutic effects of mesenchymal stem cells derived from human dental pulp (DP), adipose tissue (AD), placental amniotic membrane (PM), and umbilical cord (UC) on postmenopausal osteoporosis.

Background: Osteoporosis is a systemic bone disease characterized by bone loss and microstructural degeneration. Recent preclinical and clinical trials have further demonstrated that the transplantation of mesenchymal stem cells (MSCs) derived from human adipose tissue (AD), dental pulp (DP), placental amniotic membrane (AM), and umbilical cord (UC) tissues can serve as an effective form of cell therapy for osteoporosis. However, MSC-mediated osteoimmunology and the ability of these cells to regulate osteoclast-osteoblast differentiation varies markedly among different types of MSCs. Methods: In this study, we investigated whether transplanted allogeneic MSCs derived from AD, DP, AM, and UC tissues were able to prevent osteoporosis in an ovariectomy (OVX)-induced mouse model of osteoporosis. The homing and immunomodulatory ability of these cells as well as their effects on osteoblastogenesis and the maintenance of bone formation were compared for four types of MSCs to determine the ideal source of MSCs for the cell therapy-based treatment of OVX-induced osteoporosis. The bone formation and bone resorption ability of these four types of MSCs were analyzed using micro-computed tomography analyses and histological staining. In addition, cytokine array-based analyses of serological markers and bioluminescence imaging assays were employed to evaluate cell survival and homing efficiency. Immune regulation was determined by flow cytometer assay to reflect the mechanisms of osteoporosis treatment. Conclusion: These analyses demonstrated that MSCs isolated from different tissues have the capacity to treat osteoporosis when transplanted in vivo. Importantly, DP-MSCs infusion was able to maintain trabecular bone mass more efficiently with corresponding improvements in trabecular bone volume, mineral density, number, and separation. Among the tested MSC types, DP-MSCs were also found to exhibit greater immunoregulatory capabilities, regulating the Th17/Treg and M1/M2 ratios. These data thus suggest that DP-MSCs may represent an effective tool for the treatment of osteoporosis.

Apoptotic Vesicles Derived from Dental Pulp Stem Cells Promote Bone Formation through the ERK1/2 Signaling Pathway.

Osteoporosis is a common degenerative bone disease. The treatment of osteoporosis remains a clinical challenge in light of the increasing aging population. Human dental pulp stem cells (DPSCs), a type of mesenchymal stem cells (MSCs), are easy to obtain and have a high proliferation ability, playing an important role in the treatment of osteoporosis. However, MSCs undergo apoptosis within a short time when used in vivo; therefore, apoptotic vesicles (apoVs) have attracted increasing attention. Currently, the osteogenic effect of DPSC-derived apoVs is unknown; therefore, this study aimed to determine the role of DPSC-derived apoVs and their potential mechanisms in bone regeneration. We found that MSCs could take up DPSC-derived apoVs, which then promoted MSC osteogenesis in vitro. Moreover, apoVs could increase the trabecular bone count and bone mineral density in the mouse osteoporosis model and could promote bone formation in rat cranial defects in vivo. Mechanistically, apoVs promoted MSC osteogenesis by activating the extracellular regulated kinase (ERK)1/2 signaling pathway. Consequently, we propose a novel therapy comprising DPSC-derived apoVs, representing a promising approach to treat bone loss and bone defects.

Trabecular bone mineral density as measured by thoracic vertebrae predicts incident hip and vertebral fractures: the multi-ethnic study of atherosclerosis.

Osteoporosis affects an enormous number of patients, of all races and both sexes, and its prevalence increases as the population ages. Few studies have evaluated the association between the vertebral trabecular bone mineral density(vBMD) and osteoporosis-related hip fracture in a multiethnic population, and no studies have demonstrated the predictive value of vBMD for fractures. We sought to determine the predictive value of QCT-based trabecular vBMD of thoracic vertebrae derived from coronary artery calcium scan for hip fractures in the Multi-Ethnic Study of Atherosclerosis(MESA), a nationwide multicenter cohort included 6814 people from six medical centers across the USA and assess if low bone density by QCT can predict future fractures. Measures were done using trabecular bone measures, adjusted for individual patients, from three consecutive thoracic vertebrae (BDI Inc, Manhattan Beach CA, USA) from non-contrast cardiac CT scans. Six thousand eight hundred fourteen MESA baseline participants were included with a mean age of 62.2 ± 10.2years, and 52.8% were women. The mean thoracic BMD is 162.6 ± 46.8mg/cm3 (95% CI 161.5, 163.7), and 27.6% of participants (n = 1883) had osteoporosis (T-score 2.5 or lower). Over a median follow-up of 17.4years, Caucasians have a higher rate of vertebral fractures (6.9%), followed by Blacks (4.4%), Hispanics (3.7%), and Chinese (3.0%). Hip fracture patients had a lower baseline vBMD as measured by QCT than the non-hip fracture group by 13.6mg/cm3 [P < 0.001]. The same pattern was seen in the vertebral fracture population, where the mean BMD was substantially lower 18.3mg/cm3 [P < 0.001] than in the non-vertebral fracture population. Notably, the above substantial relationship was unaffected by age, gender, race, BMI, hypertension, current smoking, medication use, or activity. Patients with low trabecular BMD of thoracic vertebrae showed a 1.57-fold greater risk of first hip fracture (HR 1.57, 95% CI 1.38-1.95) and a nearly threefold increased risk of first vertebral fracture (HR 2.93, 95% CI 1.87-4.59) compared to normal BMD patients. There is significant correlation between thoracic trabecular BMD and the incidence of future hip and vertebral fracture. This study demonstrates that thoracic vertebrae BMD, as measured on cardiac CT (QCT), can predict both hip and vertebral fractures without additional radiation, scanning, or patient burden. Osteopenia and osteoporosis are markedly underdiagnosed. Finding occult disease affords the opportunity to treat the millions of people undergoing CT scans every year for other indications.

Associations of global biomarkers of oxidative stress with osteoporosis, bone microstructure and bone turnover: Evidence from human and animal studies

PurposeHuman evidence on the association between oxidative stress and osteoporosis is inconsistent. Fluorescent Oxidation Products (FlOPs) are global biomarkers of oxidative stress. We examined the associations of FlOPs (excitation/emission wavelengths 320/420 nm for FlOP_320, 360/420 nm for FlOP_360, and 400/475 nm for FlOP_400) with osteoporosis, bone microstructure, and bone turnover markers in humans and rats. MethodsIn humans, we conducted a 1:2 age, sex, hospital, and specimen-matched case-control study to test the association between FlOPs and osteoporosis diagnosed from dual-energy X-ray absorptiometry. In eight-week-old male Wistar rats, we administrated D-galactose and 0.9 % saline for 90 days in treatment and control groups (n = 8/group); micro-CT was used to determine bone microstructure. ResultsIn humans, higher levels of FlOP_320 (OR for per 1 SD increase = 1.49, 95 % CI: 1.01–2.20) and FlOP_360 (OR for per 1 SD increase = 1.59, 95 % CI: 1.07–2.37) were associated with increased odds of osteoporosis. FlOP_400 were not associated with osteoporosis. D-galactose treated rats, as compared with control rats, showed higher levels of FlOP_320 and MDA, and lower P1NP levels during 90 days of experiment (all P < 0.05). The D-galactose group had lower trabecular bone volume fraction (0.07 ± 0.03 vs. 0.13 ± 0.05; P = 0.008) and volumetric BMD (225.4 ± 13.8 vs. 279.1 ± 33.2 mg HA/cm3; P = 0.001) than the control group. ConclusionIn conclusion, higher FlOP_320 levels were associated with increased odds of osteoporosis, impaired bone microstructure and decreased bone formation.

Impact of sprint training on bone health: a literature review of current evidence

Specific impact of sprint training (ST) on bone health has yet to be fully explored, in particular how it affects bone mineral density (BMD) and bone structure.Aim. To investigate the ST and bone health relationship between athletes of different training intensities and nonathletes of different ages.Materials and methods. A search of databases PubMed, Embase, and Pedro was conducted from January 2009 to August 2023. The full texts of all potentially relevant studies were obtained and evaluated by three independent reviewers for inclusion.Results. The comprehensive review of eight studies indicates a positive influence of ST on bone health. Sprinters show higher cortical and trabecular BMD in the tibia than controls, with a noted age-related decline in BMD. Short distance runners demonstrate significantly better BMD, counter-movement jump performance, and grip strength compared to long-distance runners. These benefits are consistent across various age groups, including older athletes, with minimal age-related changes in mid-tibial BMD. ST is also associated with a 21% increase in tibial stress-strain index, indicating sustained bone strength, and a reduction in fracture risk in the elderly through downregulation of fracture-related microRNAs.Conclusion. ST significantly enhances bone health, particularly in improving BMD and bone microarchitecture. Incorporating ST into exercise routines may benefit athletes and older individuals. Further research is essential to understand the mechanisms and develop optimal training protocols for bone health.

Sex differences and age-related changes in vertebral body volume and volumetric bone mineral density at the thoracolumbar spine using opportunistic QCT.

To quantitatively investigate the age- and sex-related longitudinal changes in trabecular volumetric bone mineral density (vBMD) and vertebral body volume at the thoracolumbar spine in adults. We retrospectively included 168 adults (mean age 58.7 ± 9.8 years, 51 women) who received ≥7 MDCT scans over a period of ≥6.5 years (mean follow-up 9.0 ± 2.1 years) for clinical reasons. Level-wise vBMD and vertebral body volume were extracted from 22720 thoracolumbar vertebrae using a convolutional neural network (CNN)-based framework with asynchronous calibration and correction of the contrast media phase. Human readers conducted semiquantitative assessment of fracture status and bony degenerations. In the 40-60 years age group, women had a significantly higher trabecular vBMD than men at all thoracolumbar levels (p<0.05 to p<0.001). Conversely, men, on average, had larger vertebrae with lower vBMD. This sex difference in vBMD did not persist in the 60-80 years age group. While the lumbar (T12-L5) vBMD slopes in women only showed a non-significant trend of accelerated decline with age, vertebrae T1-11 displayed a distinct pattern, with women demonstrating a significantly accelerated decline compared to men (p<0.01 to p<0.0001). Between baseline and last follow-up examinations, the vertebral body volume slightly increased in women (T1-12: 1.1 ± 1.0 cm3; L1-5: 1.0 ± 1.4 cm3) and men (T1-12: 1.2 ± 1.3 cm3; L1-5: 1.5 ± 1.6 cm3). After excluding vertebrae with bony degenerations, the residual increase was only small in women (T1-12: 0.6 ± 0.6 cm3; L1-5: 0.7 ± 0.7 cm3) and men (T1-12: 0.7 ± 0.6 cm3; L1-5: 1.2 ± 0.8 cm3). In non-degenerated vertebrae, the mean change in volume was <5% of the respective vertebral body volumes. Sex differences in thoracolumbar vBMD were apparent before menopause, and disappeared after menopause, likely attributable to an accelerated and more profound vBMD decline in women at the thoracic spine. In patients without advanced spine degeneration, the overall volumetric changes in the vertebral body appeared subtle.

Aflatoxin B1 Impairs Bone Mineralization in Broiler Chickens.

Aflatoxin B1 (AFB1), a ubiquitous mycotoxin in corn-based animal feed, particularly in tropical regions, impairs liver function, induces oxidative stress and disrupts cellular pathways, potentially worsening bone health in modern broilers. A 19-day experiment was conducted to investigate the effects of feeding increasing levels of AFB1-contaminated feed (<2, 75-80, 150, 230-260 and 520-560 ppb) on bone mineralization markers in broilers (n = 360). While growth performance remained unaffected up to Day 19, significant reductions in tibial bone ash content were observed at levels exceeding 260 ppb. Micro-computed tomography results showed that AFB1 levels at 560 ppb significantly decreased trabecular bone mineral content and density, with a tendency for reduced connectivity density in femur metaphysis. Moreover, AFB1 above 230 ppb reduced the bone volume and tissue volume of the cortical bone of femur. Even at levels above 75 ppb, AFB1 exposure significantly downregulated the jejunal mRNA expressions of the vitamin D receptor and calcium and phosphorus transporters. It can be concluded that AFB1 at levels higher than 230 ppb negatively affects bone health by impairing bone mineralization via disruption of the vitamin D receptor and calcium and phosphorus homeostasis, potentially contributing to bone health issues in broilers.

Bone microarchitecture and strength assessment in adults with osteogenesis imperfecta using HR-pQCT: normative comparison and challenges.

Data on bone microarchitecture in osteogenesis imperfecta (OI) are scarce. The aim of this cross-sectional study was to assess bone microarchitecture and strength in a large cohort of adults with OI using high-resolution peripheral quantitative computed tomography (HR-pQCT) and to evaluate challenges of using HR-pQCT in this cohort. Second-generation HR-pQCT scans were obtained at the distal radius and tibia in 118 men and women with Sillence OI type I, III, or IV using an extremity-length-dependent scan protocol. In total, 102 radius and 105 tibia scans of sufficient quality could be obtained, of which 11 radius scans (11%) and 14 tibia scans (13%) had a deviated axial scan angle as compared with axial angle data of 13 young women. In the scans without a deviated axial angle and compared with normative HR-pQCT data, Z-scores at the radius for trabecular bone mineral density (BMD), number, and separation were -1.6 ± 1.3, -2.5 ± 1.4, and -2.7 (IQR: 2.7), respectively. They were -1.4 ± 1.5 and -1.1 ± 1.2 for stiffness and failure load and between ±1 for trabecular thickness and cortical bone parameters. Z-scores were significantly lower for total and trabecular BMD, stiffness, failure load, and cortical area and thickness at the tibia. Additionally, local microarchitectural inhomogeneities were observed, most pronounced being trabecular void volumes. In the scans with a deviated axial angle, the proportion of Z-scores <-4 or >4 was significantly higher for trabecular BMD and separation (radius) or most total and trabecular bone parameters (tibia). To conclude, especially trabecular bone microarchitecture and bone strength were impaired in adults with OI. HR-pQCT may be used without challenges in most adults with OI, but approximately 12% of the scans may have a deviated axial angle in OI due to bone deformities or scan positioning limitations. Furthermore, standard HR-pQCT parameters may not always be reliable due to microarchitectural inhomogeneities nor fully reflect all inhomogeneities.

Association of serum osteocalcin with bone microarchitecture and muscle mass in Beijing community-dwelling postmenopausal women.

Osteoporosis is a systemic skeletal disease with increasing bone fragility and prone to fracture. Osteocalcin (OC), as the most abundant non collagen in bone matrix, has been extensively used in clinic as a biochemical marker of osteogenesis. Two forms of OC were stated on circulation, including carboxylated osteocalcin (cOC) and undercarboxylated osteocalcin (ucOC). OC was not only involved in bone mineralization, but also in the regulation of muscle function. This study explored the relationship between serum OC, cOC, ucOC levels and bone mineral density (BMD), bone microarchitecture, muscle mass and physical activity in Chinese postmenopausal women. 216 community-dwelling postmenopausal women were randomized enrolled. All subjects completed biochemical measurements, including serum β-isomer of C-terminal telopeptides of type I collagen (β-CTX), N-terminal propeptide of type 1 procollagen (P1NP), alkaline phosphatase (ALP), OC, cOC and ucOC. They completed X-ray absorptiometry (DXA) scan to measure BMD, appendicular lean mass (ALM) and trabecular bone score (TBS). They completed high resolution peripheral quantitative CT (HR-pQCT) to assess peripheral bone microarchitectures. Serum OC, cOC and ucOC were elevated in osteoporosis postmenopausal women. In bone geometry, serum ucOC was positively related with total bone area (Tt.Ar) and trabecular area(Tb.Ar). In bone volumetric density, serum OC and ucOC were negatively associated with total volume bone mineral density (Tt.vBMD) and trabecular volume bone mineral density (Tb.vBMD). In bone microarchitecture, serum OC and ucOC were negatively correlative with Tb.N and Tb.BV/TV, and were positively correlated with Tb.Sp. Serum OC and ucOC were positively associated with Tb.1/N.SD. Serum OC was negatively related with Tb.Th. Serum ucOC was positively associated with ALM. The high level of serum OC was the risk factor of osteoporosis. ALM was the protective factor for osteoporosis. All forms of serum OC were negatively associated with BMD. Serum OC and ucOC mainly influenced microstructure of trabecular bone in peripheral skeletons. Serum ucOC participated in modulating both bone microstructure and muscle mass.

Primary Hyperparathyroidism: Assessment of the Effects of Parathyroidectomy Using Dual X-Ray Absorptiometry, Trabecular Bone Score, and Dual X-Ray Absorptiometry–Based Three-Dimensional Modeling

ObjectiveThis study aimed to evaluate the bone microstructure to determine whether curative surgery of primary hyperparathyroidism produces changes in bone mineral density (BMD), trabecular bone score (TBS), and three-dimensional (3D) dual x-ray absorptiometry (DXA) parameters and whether these changes are comparable. MethodsWe retrospectively studied 85 patients (60 women and 25 men, 60.4 ± 12.5 years) diagnosed with primary hyperparathyroidism and undergoing parathyroidectomy. Mean percent changes in BMD (lumbar spine [LS], femoral neck [FN], total hip [TH], and 1/3 radius), TBS and 3D-DXA parameters (trabecular volumetric BMD (vBMD), cortical vBMD, integral vBMD, cortical surface density (sBMD), and cortical thickness at TH) after surgery (12, 24, and/or 36 months) were calculated and compared, and we sought the determinants of these changes. ResultsAfter parathyroidectomy, BMD presented statistically significant mean increases in LS, FN, and TH during the first 3 years after surgery (P < .001), accompanied by an improvement in all 3D-DXA parameters, but there were no significant changes in 1/3 radius BMD or TBS. Cortical sBMD, trabecular vBMD, and integral vBMD reached mean increases of similar magnitude to those of FN and TH BMD. Age and preoperative serum levels of parathyroid hormone and carboxy-terminal telopeptide of type 1 collagen were significantly associated with percent changes after surgery. ConclusionWe found a benefit of parathyroidectomy for bone, with significant percent increases in LS, FN, and TH BMD up to the third year after surgery, and a qualitative benefit for the hip in both its trabecular and cortical compartments and bone strength.

Bone mineral density in young adults 5 to 11 years after adolescent metabolic and bariatric surgery for severe obesity compared to peers.

Metabolic and bariatric surgery (MBS) is associated with decreased bone mineral density (BMD) in adults. The long-term impact of MBS during adolescence on BMD is unknown. We report bone health status 5 to 11 years after Roux-en-Y gastric bypass (RYGB) and vertical sleeve gastrectomy (VSG) from the Teen-LABS study cohort. Between 2016 and 2022, BMD was measured by dual energy x-ray absorptiometry (DXA) in 106 young adults who had undergone MBS as adolescents. Volumetric BMD by peripheral quantitative computed tomography was measured on a subset. Ninety-one controls who had not undergone MBS were recruited for comparison. In cases (RYGB: mean age 26.8 ± 1.9 years, mean BMI 42.1 ± 9.9 kg/m2, VSG: mean age 25.1 ± 2.1 years, mean BMI 37.1 ± 8.4 kg/m2), compared to controls (mean age 26.5 ± 2.7 years, mean BMI 40.2 ± 8.7 kg/m2) (age p < 0.001, BMI p = 0.02), adjusted mean DXA-BMD (g/cm2) of the RYGB (n = 58) and VSG (n = 48) groups were lower at the hip (-10.0% and -6.3%), femoral neck (-9.6% and -5.7%) and ultra-distal radius (-7.9% and -7.0%; all p < 0.001), respectively. DXA-BMD did not differ between RYGB and VSG groups. Trabecular volumetric BMD at the radius and tibia were lower in the RYGB (-30% and -26%) and VSG (-15% and -14%) groups compared to the control group (p < 0.001). Greater time since MBS was associated with lower BMD Z-scores at the hip (p = 0.05) and femoral neck (p = 0.045). Percent change in body mass index (BMI) from baseline or in the first year after MBS were not associated with bone measures at a median of 9.3 years post MBS. BMD, especially of the hip and femoral neck, was lower in young adults who underwent MBS during adolescence compared to matched peers who had not undergone MBS. BMD Z-scores of the femoral neck were inversely associated with time since MBS but were not associated with BMI change.

Investigation of the level of agreement between bone mineral density and trabecular bone score regarding gender, age and body mass index

Introduction: Increasing and maintaining bone density can play a role in preventing osteoporosis, as changes in the trabecular bone score (TBS) and bone mineral density (BMD) affect bone density, especially in the spine. Objectives: The present study aimed to determine the level of agreement between TBS and BMD in patients with osteoporosis and also to investigate the relationship between these two indices with body mass index (BMI). Patients and Methods: Data were collected from 843 patients, referred to the densitometry department of Resalat hospital. BMD and TBS were measured in the subjects to determine the risk of osteoporosis. The results of BMD were measured based on T-score level. The patients’ individual and clinical characteristics were also recorded and factors influencing the prognosis of density changes were evaluated. Moreover, the effect of BMI was investigated in this study. Results: The mean age of patients was 55.5 years. The kappa coefficient and Spearman’s correlation coefficient of BMD and TBS were 0.004 and -0.015, respectively. There was a significant correlation between BMI and BMD in men. The kappa coefficient gradually increased from normal bone density to osteoporosis. There was a significant negative correlation between BMI and BMD, while a significant positive correlation between height and BMD in women was existed. On the other hand, a significant negative correlation between weight and BMD was detected accordingly. Conclusion: According to the results of our study, there is no agreement between BMD and TBS.

Changes in Vertebral Bone Density and Paraspinal Muscle Morphology Following Spaceflight and 1 Year Readaptation on Earth.

Astronauts have an increased risk of back pain and disc herniation upon returning to Earth. Thus, it is imperative to understand the effects of spaceflight and readaptation to gravity on the musculoskeletal tissues of the spine. Here we investigated whether ~6 months of spaceflight led to regional differences in bone loss within the vertebral body. Additionally, we evaluated the relationships between vertebral bone density and paraspinal muscle morphology before flight, after flight, and after readaptation on Earth. We measured vertebral trabecular bone mineral density (Tb.BMD), paraspinal muscle cross-sectional area (CSA), and muscle density in 17 astronauts using computed tomography (CT) images of the lumbar spine obtained before flight (before flight, n = 17), after flight (spaceflight, n = 17), and ~12 months of readaptation to gravitational loading on Earth (follow-up, n = 15). Spaceflight-induced declines in Tb.BMD were greater in the superior region of the vertebral body (-6.7%) than the inferior (-3.1%, p = 0.052 versus superior region) and transverse regions (-4.3%, p = 0.057 versus superior region). After a year of readaptation to Earth's gravity, Tb.BMD in the transverse region remained significantly below preflight levels (-4.66%, p = 0.0094). Paraspinal muscle CSA and muscle density declined -1.0% (p = 0.005) and -0.83% (p = 0.001) per month of spaceflight, respectively. Ultimately, bone loss in the superior vertebral body, along with fatty infiltration of paraspinal muscles and incomplete recovery even after a year of readaptation on Earth, may contribute to spinal pathology in long-duration astronauts. © 2023 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Cortical Endplate Bone Density Measured by Novel Phantomless Quantitative Computed Tomography May Predict Cage Subsidence more Conveniently and Accurately.

Previous studies have shown that bone mineral density (BMD) is a predictor of cage subsidence. Phantom-less quantitative computed tomography (PL-QCT) can measure volumetric bone mineral density (vBMD) of lumbar trabecular and cortical bone. The study of endplate vBMD (EP-vBMD) is important in predicting cage settlement after extreme lateral interbody fusion (XLIF). This study aimed to determine the risk factors for postoperative cage subsidence after XLIF, particularly focusing on the relationship between vBMD measured by automatic PL-QCT and cage subsidence. Patients who underwent XLIF surgery from January 2018 to October 2020 with a minimum of 6 months of follow-up were retrospectively included. Cage subsidence was defined as >2 mm cage sinking on the adjacent endplate in follow-up imaging evaluation. Outcome measures were localized vBMDs included EP-vBMDs with different region of interest (ROI) heights measured by PL-QCT based on a customized muscle-fat algorithm. Shapiro-Wilk test, one-way ANOVA, Mann-Whitney test, Fisher exact test, univariable and multivariable logistic regression and receiver operating characteristic (ROC) curve analysis were executed in this study. One hundred and thirteen levels of 78 patients were included in the analysis. The mean age was 65 ± 7.9 years for 11 males and 67 females. Cage subsidence occurred on 45 (39.8%) surgical levels. There was no significant difference in demographics, fused levels, or preoperative radiographic parameters. 1.25-mm EP-vBMD (0.991 [0.985,0.997], p = 0.004) and P-TB-vBMD (cage-positioned trabecular volumetric bone mineral density) (0.988 [0.977-0.999], p = 0.026) were cage-subsidence relevant according to univariate analysis. Low 1.25-mm EP-vBMD (0.992 [0.985, 0.999], p = 0.029) was an independent risk factor according to multifactorial analysis. Preoperative low EP-vBMD was an independent risk factor for postoperative cage subsidence after XLIF. EP-vBMD measured by most cortex-occupied ROI may be the optimal vBMD parameter for cage subsidence prediction.

Cooperation between T and B cells reinforce the establishment of bone metastases in a mouse model of breast cancer

Immune cells educated by the primary breast tumor and their secreted factors support the formation of bone pre-metastatic niche. Indeed, we showed that RANKL+ CD3+ T cells, specific for the 4T1 mammary carcinoma cell line, arrive at the bone marrow before metastatic cells and set the pre-metastatic niche. In the absence of RANKL expressed by T cells, there is no pre-metastatic osteolytic disease and bone metastases are completely blocked. Adding to the role of T cells, we have recently demonstrated that dendritic cells assist RANKL+ T cell activities at bone pre-metastatic niche, by differentiating into potent bone resorbing osteoclast-like cells, keeping their antigen-presenting cell properties, providing a positive feedback loop to the osteolytic profile. Here we are showing that bone marrow-derived CD19+ B cells, from 4T1 tumor-bearing mice, also express the pro-osteoclastogenic cytokine receptor activator of NFκB ligand (RANKL). Analysis of trabecular bone mineral density by conventional histomorphometry and X-ray microtomography (micro-CT) demonstrated that B cells expressing RANKL cooperate with 4T1-primed CD3+ T cells to induce bone loss. Moreover, RANKL expression by B cells depends on T cells activity, since experiments performed with B cells derived from 4T1 tumor-bearing nude BALB/c mice resulted in the maintenance of trabecular bone mass instead of bone loss. Altogether, we believe that 4T1-primed RANKL+ B cells alone are not central mediators of bone loss in vivo but when associated with T cells induce a strong decrease in bone mass, accelerating both breast cancer progression and bone metastases establishment. Although several studies performed in different pathological settings, showed that B cells, positively and negatively impact on osteoclastogenesis, due to their capacity to secret pro or anti-osteoclastogenic cytokines, as far as we know, this is the first report showing the role of RANKL expression by B cells on breast cancer-derived bone metastases scenario.

OR13-03 Assessment Of Skeletal Health Including Bone Density, Turnover, Microarchitecture And Osteoporosis In Patients With Sheehan’s Syndrome: A Prospective, Multicentric Study In Asian Indians

Abstract Disclosure: L. Das: None. B. Laway: None. J. Sahoo: None. S.K. Bhadada: None. P. Dutta: None. Introduction: Sheehan’s syndrome (SS) is a rare cause of hypopituitarism. Evidence on skeletal health in patients with this condition is limited, and data on bone geometry, structure and volumetric bone mineral density (BMD) are lacking. We aimed to comprehensively explore skeletal fragility in a multicentric cohort of treated SS. Patients and Methods: Patients with SS were recruited for analysis of demographic, clinico-biochemical and hormonal profile including bone turnover markers. Areal BMD, T- and Z-scores and trabecular bone score (TBS) were evaluated using DXA. In a subset of patients (n=29) as well as age-and BMI-matched controls (n=34), high-resolution peripheral quantitative computed tomography (HRpQCT, XtremeCT II, Scanco Medical AG, Switzerland) was performed to assess bone geometry and microarchitecture. Results: There were a total of 105 patients with SS with a mean age 45.2 ± 10.5 years and a lag of 7.4 ± 5.5 years from disease onset to diagnosis. Regular levothyroxine replacement was ongoing in 91.2% and glucocorticoid replacement in 86.1% of the cohort. Past HRT replacement was done in 66.7% patients. Bone turnover markers (P1NP, CTX) were not significantly different between cases and controls. The T- score [-2.3 (-3.0 to -1.6) vs -1.5 (-3.0 to -0.7)] and Z-score [-1.4 (-2.1 to -1.2) vs -0.6 (-2.1 to -0.1)] at the lumbar spine (LS) and the T- score [-1.8 (-2.3 to -1.3) vs -0.8 (-2.1 to -0.1)] and Z-score [-1.1 (-1.7 to -0.4) vs -0.4 (-1.0 to 0.2)] at the femoral neck (FN) were lower in cases as compared to controls (trend towards significance). Osteopenia or osteoporosis was prevalent in significantly greater proportion of the cases as compared to controls, at LS (96.3% vs 64.7%), FN (91.7% vs 47%) and ultradistal radius (65.2% vs 11.8%). Bone microarchitectural assessment showed no significant differences between TBS, or bone geometry. However, trabecular volumetric bone mineral density was higher at both tibia (p&amp;lt;0.05) and radius (p&amp;gt;0.05) in cases as opposed to age-and BMI-matched controls. There was a weak negative correlation between glucocorticoid and levothyroxine replacement duration and BMD at both LS and FN (p&amp;lt;0.05), but not with replacement dose. Conclusion: Osteopenia-osteoporosis is highly prevalent in SS. BMD at both LS and FN is negatively correlated with duration of glucocorticoid and levothyroxine exposure. There are no significant differences in bone microarchitecture or geometry but tibial trabecular volumetric BMD is greater in treated SS. Presentation: Friday, June 16, 2023

FRI072 Biomechanical CT To Assess Bone After Sleeve Gastrectomy In Adolescents With Obesity- Prospective Longitudinal Study

Abstract Disclosure: V. Singhal: None. F.A. Huber: None. S. Tuli: None. M. Bouxsein: None. M. Misra: None. M.A. Bredella: None. Background and Objective: Sleeve gastrectomy (SG) is effective in treating cardiometabolic complications of obesity but is associated with bone loss. Our aim was to determine the effect of SG on the lumbar spine by biomechanical computed tomography (CT) analysis in adolescents/young adults with obesity. We hypothesized that SG would lead to a decrease in strength and BMD compared to non-surgical controls. Methods: 12-month prospective non-randomized study of adolescents/young adults with obesity who either underwent SG (N=29) or were followed without surgery (controls, N=30). At baseline and 12 months, participants underwent QCT of L1 and L2 for biomechanical assessment and MRI of the abdomen and mid-thigh for body composition assessment. 12-month changes between groups were compared using Student’s t-test, and changes within groups were assessed using paired t-tests. Analyses were controlled for baseline and 12-month changes in BMI by multivariable analyses. Regression analysis was performed to evaluate the effect of body composition on bone parameters. Results: Participants in the SG group had a higher baseline BMI than controls (p=0.01) and lost an average of 34.3±13.6 kg 12 months after surgery, whereas weight was unchanged in controls (p&amp;lt;0.001). There were significant reductions in abdominal adipose tissue and thigh muscle area in the SG group compared to controls (p&amp;lt;0.001). Significant decreases in bone strength [-609 (-928, -291) vs. 103 (-173, 380) N], bending stiffness (-0.08 ± 0.16 vs. 0.07 ± 0.15 kNm/rad), average vBMD (-12 ± 12 vs. 0 ± 13 mg/cm3) and trabecular vBMD (-15 ± 13 vs. 2 ± 13 mg/cm³) were noted in the SG vs. control groups (all p&amp;lt;0.001). After controlling for change in BMI, a 12-month reduction in cortical BMD was significant in the SG group compared to controls (p=0.02). Reductions in strength and trabecular BMD were associated with reductions in BMI, visceral adipose tissue, and muscle (p≤0.03). Conclusion: Adolescents undergoing SG had a decrease in strength and volumetric BMD of the lumbar spine compared to non-surgical controls; reductions in cortical BMD were independent of weight reductions over the study duration. These changes were associated with a decrease in visceral fat and muscle mass. Presentation: Friday, June 16, 2023