High-resolution Peripheral Quantitative Computed Tomography Research Articles

Blast injury on harbour porpoises (Phocoena phocoena) from the Baltic Sea after explosions of deposits of World War II ammunition.

Harbour porpoises are under pressure from increasing human activities. This includes the detonation of ammunition that was dumped in large amounts into the sea during and after World War II. In this context, forty-two British ground mines from World War II were cleared by means of blasting in the period from 28 to 31 August 2019 by a NATO unit in the German Exclusive Economic Zone within the marine protected area of Fehmarn Belt in the Baltic Sea, Germany. Between September and November 2019, 24 harbour porpoises were found dead in the period after those clearing events along the coastline of the federal state of Schleswig-Holstein and were investigated for direct and indirect effects of blast injury. Health evaluations were conducted including examinations of the brain, the air-filled (lungs and gastrointestinal tract) and acoustic organs (melon, acoustic fat in the lower jaw, ears and their surrounding tissues). The bone structure of the tympano-periotic complexes was examined using high-resolution peripheral quantitative computed tomography (HR-pQCT). In 8/24 harbour porpoises, microfractures of the malleus, dislocation of middle ear bones, bleeding, and haemorrhages in the melon, lower jaw and peribullar acoustic fat were detected, suggesting blast injury. In addition, one bycaught animal and another porpoise with signs of blunt force trauma also showed evidence of blast injury. The cause of death of the other 14 animals varied and remained unclear in two individuals. Due to the vulnerability and the conservation status of harbour porpoise populations in the Baltic Sea, noise mitigation measures must be improved to prevent any risk of injury. The data presented here highlight the importance of systematic investigations into the acute and chronic effects of blast and acoustic trauma in harbour porpoises, improving the understanding of underwater noise effects and herewith develop effective measures to protect the population level.

Effect of microstructure on trabecular-bone fracture: numerical analysis

Trabecular bone tissue with its complicated microstructural morphology can exhibit complex and random fracture patterns. This paper focuses on the effect of morphology of bone tissue on processes of its deformation and fracture. For this purpose, three-dimensional unit cells of trabecular bone tissue were generated based on the scans of human distal tibial bone obtained with high-resolution peripheral quantitative computed tomography (HR-pQCT). Mechanical behavior of porous structure of trabecular bone was investigated under conditions of applied tensile and compressive loads employing a model of degradation of elastic properties, numerically implemented with finite-element analysis. The calculations were performed in Simulia Abaqus using the UMAT custom subroutine.

Failure behaviour of human trabecular bone

A trabecular bone tissue with its complex microstructural morphology can demonstrate a complex and random pattern of fracture. This paper analyses the effect of material’s mechanical behaviour on failure modelling of human trabecular bone. For this purpose, a 3D unit cell of trabecular tissue was obtained from scans of human distal tibia performed with high-resolution peripheral quantitative computed tomography (HR-pQCT). In simulations, two types of fracture of trabeculae were considered - brittle and ductile, with respective elastic and elastoplastic formulations. Two types of loading – tension and compression – were applied to the unit cell in order to assess its stress state and locations of the failure onset. Positions of damaged areas in case of brittle-fracture approach differed for tension and compression, while the same damage regions were observed for the ductile criterion in both loading conditions. It was found that the first modelling approach resulted in about two times higher effective strength of trabecular bone as compared to that for the second approach: 11.49 MPa and 4.94 MPa, respectively. The calculated values of effective strength for brittle and ductile material models are in good agreement with the magnitudes of tensile and compressive strength of trabecular bone reported in the literature. Effective parameters of the trabecular bone tissue – ultimate compressive and tensile strength as well as yield stress – are considerably lower than those of individual trabeculae: some 8% of the respective magnitudes for trabeculae.

Assessment of the healing of conservatively-treated scaphoid fractures using HR-pQCT.

Improving the clinical outcome of scaphoid fractures may benefit from adequate monitoring of their healing in order to for example identify complications such as scaphoid nonunion at an early stage and to adjust the treatment strategy accordingly. However, quantitative assessment of the healing process is limited with current imaging modalities. In this study, high-resolution peripheral quantitative computed tomography (HR-pQCT) was used for the first time to assess the changes in bone density, microarchitecture, and strength during the healing of conservatively-treated scaphoid fractures. Thirteen patients with a scaphoid fracture (all confirmed on HR-pQCT and eleven on CT) received an HR-pQCT scan at baseline and three, six, twelve, and 26weeks after first presentation at the emergency department. Bone mineral density (BMD) and trabecular microarchitecture of the scaphoid bone were quantified, and failure load (FL) was estimated using micro-finite element analysis. Longitudinal changes were evaluated with linear mixed-effects models. Data of two patients were excluded due to surgical intervention after the twelve-week follow-up visit. In the eleven fully evaluable patients, the fracture line became more apparent at 3weeks. At 6weeks, individual trabeculae at the fracture region became more difficult to identify and distinguish from neighboring trabeculae, and this phenomenon concerned a larger region around the fracture line at 12weeks. Quantitative assessment showed that BMD and FL were significantly lower than baseline at all follow-up visits with the largest change from baseline at 6weeks (-13.6% and-23.7%, respectively). BMD remained unchanged thereafter, while FL increased. Trabecular thickness decreased significantly from baseline at three (-3.9%), six (-6.7%), and twelve (-4.4%) weeks and trabecular number at six (-4.5%), twelve (-7.3%), and 26 (-7.9%) weeks. Trabecular separation was significantly higher than baseline at six (+13.3%), twelve (+19.7%), and 26 (+16.3%) weeks. To conclude, this explorative HR-pQCT study showed a substantial decrease in scaphoid BMD, Tb.Th, and FL during the first 6weeks of healing of conservatively-treated scaphoid fractures, followed by stabilization or increase in these parameters. At 26weeks, BMD, trabecular microarchitecture, and FL were not returned to baseline values.

Cortical bone thickness of the distal radius predicts the local bone mineral density.

AimsThe distal radius is a major site of osteoporotic bone loss resulting in a high risk of fragility fracture. This study evaluated the capability of a cortical index (CI) at the distal radius to predict the local bone mineral density (BMD).MethodsA total of 54 human cadaver forearms (ten singles, 22 pairs) (19 to 90 years) were systematically assessed by clinical radiograph (XR), dual-energy X-ray absorptiometry (DXA), CT, as well as high-resolution peripheral quantitative CT (HR-pQCT). Cortical bone thickness (CBT) of the distal radius was measured on XR and CT scans, and two cortical indices mean average (CBTavg) and gauge (CBTg) were determined. These cortical indices were compared to the BMD of the distal radius determined by DXA (areal BMD (aBMD)) and HR-pQCT (volumetric BMD (vBMD)). Pearson correlation coefficient (r) and intraclass correlation coefficient (ICC) were used to compare the results and degree of reliability.ResultsThe CBT could accurately be determined on XRs and highly correlated to those determined on CT scans (r = 0.87 to 0.93). The CBTavg index of the XRs significantly correlated with the BMD measured by DXA (r = 0.78) and HR-pQCT (r = 0.63), as did the CBTg index with the DXA (r = 0.55) and HR-pQCT (r = 0.64) (all p < 0.001). A high correlation of the BMD and CBT was observed between paired specimens (r = 0.79 to 0.96). The intra- and inter-rater reliability was excellent (ICC 0.79 to 0.92).ConclusionThe cortical index (CBTavg) at the distal radius shows a close correlation to the local BMD. It thus can serve as an initial screening tool to estimate the local bone quality if quantitative BMD measurements are unavailable, and enhance decision-making in acute settings on fracture management or further osteoporosis screening.Cite this article: Bone Joint Res 2021;10(12):820–829.

Parathyroid Hormone-Related Changes of Bone Structure.

Parathyroid hormone (PTH) increases the release of serum calcium through osteoclasts, which leads to bone resorption. Primary, PTH stimulates osteoblasts leading to increase RANKL (receptor activator for nuclear factor kappa-B ligand) expression and thus differentiation of osteoclasts. In kidneys, PTH increases calcium and decrease phosphate reabsorption. In kidneys, PTH stimulates 1alpha-hydroxylase to synthesize active vitamin D. Primary hyperparathyroidism (PHPT) is characterized by skeletal or renal complications. Nowadays, the classical form of PHPT is less seen and asymptomatic or subclinical (oligo symptomatic) forms are more frequent. Previously, it was thought that cortical bone is preferably affected by PHPT and that predispose bones to fracture at sites with a higher amount of cortical bone. However, an increased risk of vertebral fractures has been found by most of the studies showing that also trabecular bone is affected. Bone Mass measurement (BMD) at all skeletal sites is advised, but another specific tool for fracture assessment is needed. Trabecular bone score (TBS), an indirect measure of trabecular bone, maybe a useful method to estimate fracture risk. TBS is associated with vertebral fractures in PHPT regardless of BMD, age, BMI and gender. Furthermore, there is an association between TBS and high resolution peripheral quantitative computed tomography (HR-pQCT) parameters in the trabecular and cortical compartment. However, studies considering the effect of PHPT treatment on TBS are more conflicting. Secondary hyperparathyroidism caused by vitamin D deficiency was associated with impaired bone microarchitecture in all age categories, as measured by TBS and Hr-pQCT with further improvement after treatment with vitamin D.

Bone microstructure changes due to once-/twice-weekly teriparatide administration: A report of five cases using high-resolution peripheral quantitative computed tomography

This study was conducted with the aim of presenting cases in which high-resolution peripheral quantitative computed tomography (HR-pQCT) was used to investigate changes in the bone microstructure due to once-weekly/twice-weekly administration of teriparatide (TPTD). Of osteoporosis patients who participated in a non-inferiority trial (TWICE study: once-weekly vs twice-weekly TPTD) with lumbar bone mineral density as the primary endpoint, five cases scanned by HR-pQCT before TPTD administration were analysed. Two cases were given once-weekly TPTD, three were given twice-weekly TPD, and HR-pQCT was repeated after 48 weeks. A sufficient anabolic effect of once-weekly/twice-weekly TPTD on the trabecular and cortical bone at the tibia was obtained. In addition, the average change in cortical porosity (Ct.Po) was only 0.3% in the tibia and 0.2% in the radius. These findings indicate that once-weekly and twice-weekly TPTD can be expected to improve the bone microstructure, and the increase in Ct.Po may be suppressed.

Individual aspects in eldery patients with fragility fractures

Due to our ageing population, the number of elderly patients who are treated in the emergency department due to low-energy trauma (e.g., tripping) continues to rise. These minor accidents often result in fragility fractures classically located in the proximal humerus, distal radius, spine, pelvis, and near the hip joint. Pre-existing conditions, polypharmacy, and general frailty increase the risk of fragility fractures in this patient population. Geriatric trauma fractures and especially insufficiency fractures of the posterior pelvic ring are often difficult to diagnose by plain X‑ray. Therefore, in geriatric trauma patients, cross-sectional imaging, e.g., computed tomography (CT), dual-energy CT (DECT), or magnetic resonance imaging (MRI), should be considered early for reliable evaluation of asuspected fracture. This also allows for the identification of older fractures. Particularly in cognitively impaired elderly patients, difficult examination conditions or an unclear fall event, cross-sectional imaging is often indicated. However, this may also involve risks, e.g., use of contrast medium in patients with impaired renal function, so that each case must be considered individually. Furthermore, the diagnosis and treatment of osteoporosis, which is an underlying disease that leads to fragility fractures, is of particular importance. In the diagnostic workup, measurement of bone density using dual energy X‑ray absorptiometry (DXA) is the standard method according to guidelines. In specific situations, high-resolution peripheral quantitative CT (HR-pQCT) may also be used. Due to the special challenges of correctly detecting fragility fractures and being able to quickly initiate adequate therapy, good cooperation between radiologists and trauma surgeons is necessary.

Dairy Food Intake Is Not Associated with Measures of Bone Microarchitecture in Men and Women: The Framingham Osteoporosis Study.

Previous studies reported that dairy foods are associated with higher areal bone mineral density (BMD) in older adults. However, data on bone strength and bone microarchitecture are lacking. We determined the association of dairy food intake (milk, yogurt, cheese, milk + yogurt, and milk + yogurt + cheese, servings/week) with high resolution peripheral quantitative computed tomography (HR-pQCT) measures of bone (failure load, cortical BMD, cortical thickness, trabecular BMD, and trabecular number). This cross-sectional study included participants with diet from a food frequency questionnaire (in 2005–2008 and/or 1998–2001) and measurements of cortical and trabecular BMD and microarchitecture at the distal tibia and radius (from HR-pQCT in 2012–2015). Sex-specific multivariable linear regression estimated the association of dairy food intake (energy adjusted) with each bone measure adjusting for covariates. Mean age was 64 (SD 8) years and total milk + yogurt + cheese intake was 10.0 (SD 6.6) and 10.6 (6.4) servings/week in men and women, respectively. No significant associations were observed for any of the dairy foods and bone microarchitecture measures except for cheese intake, which was inversely associated with cortical BMD at the radius (p = 0.001) and tibia (p = 0.002) in women alone. In this cohort of primarily healthy older men and women, dairy intake was not associated with bone microarchitecture. The findings related to cheese intake and bone microarchitecture in women warrant further investigation.

Sequential Therapy With Recombinant Human IGF-1 Followed by Risedronate Increases Spine Bone Mineral Density in Women With Anorexia Nervosa: A Randomized, Placebo-Controlled Trial.

Anorexia nervosa is complicated by low bone mineral density (BMD) and increased fracture risk associated with low bone formation and high bone resorption. The lumbar spine is most severely affected. Low bone formation is associated with relative insulin-like growth factor 1 (IGF-1) deficiency. Our objective was to determine whether bone anabolic therapy with recombinant human (rh) IGF-1 used off-label followed by antiresorptive therapy with risedronate would increase BMD more than risedronate or placebo in women with anorexia nervosa. We conducted a 12-month, randomized, placebo-controlled study of 90 ambulatory women with anorexia nervosa and low areal BMD (aBMD). Participants were randomized to three groups: 6 months of rhIGF-1 followed by 6 months of risedronate ("rhIGF-1/Risedronate") (n= 33), 12 months of risedronate ("Risedronate") (n= 33), or double placebo ("Placebo") (n= 16). Outcome measures were lumbar spine (1° endpoint: postero-anterior [PA] spine), hip, and radius aBMD by dual-energy X-ray absorptiometry (DXA), and vertebral, tibial, and radial volumetric BMD (vBMD) and estimated strength by high-resolution peripheral quantitative computed tomography (HR-pCT) (for extremity measurements) and multi-detector computed tomography (for vertebral measurements). At baseline, mean age, body mass index (BMI), aBMD, and vBMD were similar among groups. At 12 months, mean PA lumbar spine aBMD was higher in the rhIGF-1/Risedronate (p= 0.03) group and trended toward being higher in the Risedronate group than Placebo. Mean lateral lumbar spine aBMD was higher, in the rhIGF-1/Risedronate than the Risedronate or Placebo groups (p< 0.05). Vertebral vBMD was higher, and estimated strength trended toward being higher, in the rhIGF-1/Risedronate than Placebo group (p< 0.05). Neither hip or radial aBMD or vBMD, nor radial or tibial estimated strength, differed among groups. rhIGF-1 was well tolerated. Therefore, sequential therapy with rhIGF-1 followed by risedronate increased lateral lumbar spine aBMD more than risedronate or placebo. Strategies that are anabolic and antiresorptive to bone may be effective at increasing BMD in women with anorexia nervosa. © 2021 American Society for Bone and Mineral Research (ASBMR).

Decreased cortical bone density and mechanical strength with associated elevated bone turnover markers at peri-pubertal peak height velocity: a cross-sectional and longitudinal cohort study of 396 girls with adolescent idiopathic scoliosis.

As part of the studies related to aetiopathogenesis of AIS, we assessed bone qualities, bone mechanical strength and bone turnover markers (BTMs) focusing at the peri-pubertal period and PHV in AIS girls. 396 AIS girls in two separate cohorts were studied. Skeletal maturity was assessed using the validated thumb ossification composite index (TOCI). Bone qualities and strength were evaluated with high-resolution peripheral quantitative computed tomography (HR-pQCT) and finite element analysis (FEA). Cohort-A included 179 girls (11.95 ± 0.95years old). Girls at TOCI-4 had numerically the highest height velocity (0.71 ± 0.24cm/month) corresponding to the PHV. Subjects at TOCI-4 had lower cortical volumetric BMD (672.36 ± 39.07mg/mm3), cortical thickness (0.68 ± 0.08mm) and apparent modulus (1601.54 ± 243.75N/mm2) than: (a) those at TOCI-1-3 (724.99 ± 32.09mg/mm3 (p < 0.001), 0.79 ± 0.11mm (p < 0.001) and 1910.88 ± 374.75N/mm2 (p < 0.001), respectively) and (b) those at TOCI-8 (732.28 ± 53.75mg/mm3 (p < 0.001), 0.84 ± 0.14mm (p < 0.001), 1889.11 ± 419.37N/mm2 (p < 0.001), respectively). Cohort-B included 217 girls (12.22 ± 0.89years old). Subjects at TOCI-4 had higher levels of C-terminal telopeptide of type 1 collagen (1524.70 ± 271.10pg/L) and procollagen type 1N-terminal propeptide (941.12 ± 161.39µg/L) than those at TOCI-8 (845.71 ± 478.55pg/L (p < 0.001) and 370.08 ± 197.04µg/L (p < 0.001), respectively). AIS girls had decreased cortical bone density and bone mechanical strength with elevated BTMs at PHV. Coupling of PHV with decreased cortical and FEA parameters could provide the link to the previously reported observation that low BMD could contribute as one of the prognostic factors for curve progression that mostly occurs during PHV in AIS.

Reference microarchitectural values measured by HR-pQCT in a Franco-Swiss cohort of young adult women

High-resolution peripheral quantitative computed tomography (HR-pQCT) non-invasively measures three-dimensional bone microarchitectural parameters and volumetric bone mineral density. Previous studies established normative reference HR-pQCT datasets for several populations, but there were few data assessed in a reference group of young women with Caucasian ethnicity living in Western Europe. It is important to obtain different specific reference dataset for a valid interpretation of cortical and trabecular microarchitecture data. The aim of our study was to find the population with the most optimal bone status in order to establish a descriptive reference HR-pQCT dataset in a young and healthy normal-weight female cohort living in a European area including Geneva, Switzerland, Lyon and Saint-Etienne, France. We constituted a cross-sectional cohort of 339 women aged 19-41years with a BMI > 18 and < 30kg/m2. All participants had HR-pQCT measurements at both non-dominant distal radius and tibia sites. We observed that microarchitectural parameters begin to decline before the age of 30years. Based on a discriminant analysis, the optimal bone profile in this population was observed between the age range of 22 to 27years. Consequently, we considered 43 participants aged 22-27years to establish a reference dataset with median values and percentiles. This is the first study providing reference values of HR-pQCT measurements considering specific age bounds in a Franco-Swiss female cohort at the distal radius and tibia sites.

Gait speed and spasticity are independently associated with estimated failure load in the distal tibia after stroke: an HR-pQCT study

(1) To examine the influence of stroke on distal tibia bone properties and (2) the association between these properties and clinical outcomes in people with chronic stroke. Sixty-four people with stroke (age, 60.8 ± 7.7years; time since stroke, 5.7 ± 3.9years) and 64 controls (age: 59.4 ± 7.8years) participated in this study. High-resolution peripheral quantitative computed tomography (HR-pQCT) was used to scan the bilateral distal tibia, and estimated failure load was calculated by automated finite element analysis. Echo intensity of the medial gastrocnemius muscle and blood flow of the popliteal artery were assessed with ultrasound. The 10-m walk test (10MWT), Fugl-Meyer Motor Assessment (FMA), and Composite Spasticity Scale (CSS) were also administered. The percent side-to-side difference (%SSD) in estimated failure load, cortical area, thickness, and volumetric bone mineral density (vBMD), and trabecular and total vBMD were significantly greater in the stroke group than their control counterparts (Cohen's d = 0.48-1.51). Isometric peak torque and echo intensity also showed significant within- and between-groups differences (p ≤ 0.01). Among HR-pQCT variables, the%SSD inestimated failure load was empirically chosen as one example of the strong discriminators between the stroke group and control group, after accounting for other relevant factors. The 10MWT and CSS subscale for ankle clonus remained significantly associated with the %SSD in estimated failure load after adjusting for other relevant factors (p ≤ 0.05). The paretic distal tibia showed more compromised vBMD, cortical area, cortical thickness, and estimated failure load than the non-paretic tibia. Gait speed and spasticity were independently associated with estimated failure load. As treatment programs focusing on these potentially modifiable stroke-related impairments are feasible to administer, future studies are needed to determine the efficacy of such intervention strategies for improving bone strength in individuals with chronic stroke.

Bone microarchitecture of the distal fibula assessed by HR-pQCT.

The distal fibula represents one of the most common fracture sites, and its epidemiology is characterized by a high incidence in both adolescence and the elderly. While fracture occurrence is influenced by trauma mechanism, a possible underlying skeletal microarchitectural deterioration in certain patient groups remains elusive. The purpose of this study was to determine the influence of age, sex, and overall skeletal status on fibular microarchitecture. We analyzed the microarchitecture of the distal fibula in 300 people by high-resolution peripheral quantitative computed tomography (HR-pQCT). Three areal bone mineral density (aBMD) groups (normal, osteopenia, osteoporosis; n=100 per group) based on the concurrent assessment of aBMD by dual-energy X-ray absorptiometry (DXA) at the lumbar spine and total hip were established. Next to group comparisons, linear and non-linear regression analyses were carried out to assess the association between age, sex, BMI, tibial and fibular microarchitecture. While women had lower values for both trabecular bone volume fraction (BV/TVd, p<0.001) and cortical thickness (Ct.Thd, p<0.001) than men, osteoporosis by DXA negatively affected these parameters in both sexes. Remarkably, cortical but not trabecular microarchitecture declined with age, with a stronger decrease in females compared to males (Ct.Thd female -10.0μm/year (95% CI: -12.2 to -7.7μm/year), male -4.0μm/year (95% CI: -6.3 to -1.7μm/year)). Moderate positive associations between distal tibial and fibular microarchitecture were noted (e.g., BV/TVd R2=0.54, Ct.Thd R2=0.58). In summary, we here demonstrate the severe negative effects of age, female sex and osteoporosis on distal fibula bone mineralization and microarchitecture. The presented findings are likely to explain the higher susceptibility to distal fibula fractures in elderly women (independent of trauma mechanism). These alterations in fibular bone quality must be taken into account in the context of fracture prevention and treatment (e.g., osteosynthesis planning).

Reference data and calculators for second-generation HR-pQCT measures of the radius and tibia at anatomically standardized regions in White adults.

To provide age- and sex-specific reference data for high-resolution peripheral quantitative computed tomography (HR-pQCT) measures of the distal and diaphyseal radius and tibia acquired using a second-generation scanner and percent-of-length offsets proximal from the end of the bone. Data were acquired in White adults (aged 18-80years) living in the Midwest region of the USA. HR-pQCT scans were performed at the 4% distal radius, 30% diaphyseal radius, 7.3% distal tibia, and 30% diaphyseal tibia. Centile curves were fit to the data using the LMS approach. Scans of 867 females and 317 males were included. The fitted centile curves reveal HR-pQCT differences between ages, sexes, and sites. They also indicate differences when compared to data obtained by others using fixed length offsets. Excel-based calculators based on the current data were developed and are provided to enable computation of subject-specific percentiles, z-scores, and t-scores and to plot an individual's outcomes on the fitted curves. In addition, regression equations are provided to convert estimated failure load acquired with the conventional criteria utilized with first-generation scanners and those specifically developed for second-generation scanners. The current study provides unique data and resources. The combination of the reference data and calculators provide clinicians and investigators an ability to assess HR-pQCT outcomes in an individual or population of interest, when using the described scanning and analysis procedure. Ultimately, the expectation is these data will be expanded over time so the wealth of information HR-pQCT provides becomes increasingly interpretable and utilized.

The Negative Impacts of Acromegaly on Bone Microstructure Not Fully Reversible

PurposeThis study aimed to evaluate the bone turnover markers and bone microarchitecture parameters derived from high-resolution peripheral quantitative computed tomography (HR-pQCT) in active and controlled acromegaly patients.MethodsThis cross-sectional study involved 55 acromegaly patients from a tertiary hospital (23 males and 32 females, aged 45.0 ± 11.6 years). Firstly, growth hormone (GH), insulin-like growth factor-1 (IGF-1), and markers for bone turnover were assessed. Next, we derived peripheral bone microstructure parameters and volumetric bone mineral density (vBMD) through HR-pQCT. These parameters were compared between acromegaly patients and 110 healthy controls, as well as between 27 active and 28 controlled acromegaly patients. Moreover, the relationship between GH/IGF-1 and bone microstructure parameters was analyzed through multiple linear regression.ResultsAs compared with healthy controls, acromegaly patients exhibited elevated cortical vBMD, reduced trabecular vBMD, and increased trabecular inhomogeneity in the distal radius and tibia. While controlled acromegaly patients had slower bone turnover, they did not necessarily have better bone microstructure relative to active patients in intergroup comparison. Nevertheless, multiple regression indicated that higher IGF-1 was associated with lower tibial stiffness and failure load. Additionally, males with higher IGF-1 typically had larger trabecular separation, lower trabecular number, and larger cortical pores in the radius. Moreover, patients with elevated GH typically had more porous cortical bone in the radius and fewer trabeculae in the tibia. However, the compromised bone strength in active patients was partially compensated by increased bone thickness. Furthermore, no significant linkage was observed between elevated GH/IGF-1 and the most important HR-pQCT parameters such as trabecular volumetric bone density.ConclusionAcromegaly adversely affected bone quality, even in controlled patients. As the deterioration in bone microstructure due to prolonged GH/IGF-1 exposure was not fully reversible, clinicians should be aware of the bone fragility of acromegaly patients even after they had achieved biochemical remission.

Performance of HR-pQCT, DXA, and FRAX in the discrimination of asymptomatic vertebral fracture in postmenopausal Chinese women

SummaryVolumetric bone density (vBMD) and trabecular microarchitecture measured by high-resolution peripheral quantitative computed tomography (HR-pQCT) can discriminate the patients with high risk of asymptomatic vertebral fracture (VF) in postmenopausal Chinese women. These findings suggested that HR-pQCT could provide additional information on bone quality of the patients with asymptomatic VF.IntroductionAlthough there were several studies using HR-pQCT to investigate asymptomatic VF, it remains uncertain if HR-pQCT parameters can discriminate asymptomatic VF patients, especially in Chinese population. The purpose of this study was to investigate whether bone quality measured by HR-pQCT could discriminate asymptomatic VF independent of hip areal bone mineral density (aBMD) measured by dual-energy x-ray absorptiometry (DXA) and fracture risks evaluated using built-in Fracture Risk Assessment Tool (FRAXBMD).MethodsThis is a nested case–control study. One hundred seventy-five ambulatory Chinese postmenopausal women aged 60–79 years were retrieved from Normative Reference Standards (NRS) cohort in Hong Kong. DXA was used to identify VF from lateral spine images (VFA) using Genant’s semi-quantitative method. Major osteoporotic fracture risk was calculated using FRAX tool. HR-pQCT was used to assess vBMD, microarchitecture, and estimated strength at both distal radius and tibia. Comparison of HR-pQCT parameters between asymptomatic VF and control was performed using covariance analysis. Logistic regression analysis was performed for calculating the adjusted odds ratio (OR) with 95% confidence intervals (CI) of fracture status as per SD decrease in HR-pQCT parameters.ResultsWomen with asymptomatic VF were older than those of the control in our NRS cohort. Nevertheless, after adjusted for covariance, asymptomatic VF showed significantly lower trabecular vBMD (Tb.vBMD) at radius but higher SMI at tibia as compared with those of the control. Tb.vBMD at radius yielded the highest value of area under the curve (AUC) as compared with total hip aBMD and FRAXBMD. However, no significant difference was found among each other.ConclusionTb.vBMD at the radius and SMI at the tibia provided by HR-pQCT can discriminate asymptomatic VF independent of hip aBMD and FRAXBMD by DXA in postmenopausal women.

Association between bone shape and the presence of a fracture in patients with a clinically suspected scaphoid fracture

Scaphoid fractures are difficult to diagnose with current imaging modalities. It is unknown whether the shape of the scaphoid bone, assessed by statistical shape modeling, can be used to differentiate between fractured and non-fractured bones. Therefore, the aim of this study was to investigate whether the presence of a scaphoid fracture is associated with shape modes of a statistical shape model (SSM). Forty-one high-resolution peripheral quantitative computed tomography (HR-pQCT) scans were available from patients with a clinically suspected scaphoid fracture of whom 15 patients had a scaphoid fracture. The scans showed no motion artefacts affecting bone shape. The scaphoid bones were semi-automatically contoured, and the contours were converted to triangular meshes. The meshes were registered, followed by principal component analysis to determine mean shape and shape modes describing shape variance. The first five out of the forty shape modes cumulatively explained 87.8% of the shape variance. Logistic regression analysis was used to study the association between shape modes and fracture presence. The regression models were used to classify the 41 scaphoid bones as fractured or non-fractured using a cut-off value that maximized the sum of sensitivity and specificity. The classification of the models was compared with fracture diagnosis on HR-pQCT. A regression model with four shape modes had an area under the ROC-curve of 72.3% and correctly classified 75.6% of the scaphoid bones (fractured: 60.0%, non-fractured: 84.6%). To conclude, fracture presence in patients with a clinically suspected scaphoid fracture appears to be associated with the shape of the scaphoid bone.

Volumetric Bone Mineral Density Measured by HR-pQCT in Patients with Psoriasis or Psoriatic Arthritis: A Systematic Review and Meta-Analysis with Trial Sequential Analysis.

Bone health in psoriasis and psoriatic arthritis has been emphasized in recent years. Novel imaging modalities allow investigations into volumetric bone mineral density (vBMD) and bone microstructure in psoriatic patients. However, literature regarding vBMD measured by high-resolution peripheral quantitative computed tomography (HR-pQCT) is inconclusive. We conducted a systematic review and meta-analysis to evaluate vBMD in patients with psoriatic disease. We searched PubMed, EMBASE, Web of Science, and Cochrane Library for relevant observational studies. A random-effects meta-analysis with trial sequential analysis (TSA) was performed. The pooled mean difference (MD) and 95% confidence interval (CI) were calculated. Five studies with 780 patients were included. Patients with psoriatic disease showed a lower average vBMD than controls (MD −14.90; 95% CI −22.90 to −6.89; TSA-adjusted CI −23.77 to −6.03; I2 = 41%). Trabecular vBMD and cortical vBMD results were inconclusive because of the small sample size. Patients recruited in Asia and those whose vBMD were measured at the distal radius exhibited a lower average vBMD than controls. Further research should clarify the association of psoriasis with bone microstructure and the underlying pathophysiology.

Association Between DXA And HR-pQCT Measurements Of BMD In Active, Recruit-aged Men And Women

Dual-energy X-ray absorptiometry (DXA) areal bone mineral density (aBMD) measurements are routinely employed to assess fracture risk despite the limitations of a two-dimensional, estimated projection of bone volume. Conversely, high-resolution peripheral quantitative computed tomography (HR-pQCT) provides three-dimensional volumetric BMD (vBMD) measurements of total, trabecular, and cortical bone, offering better characterization of fracture risk. It remains unclear whether regional aBMD accurately reflects vBMD of specific bone compartments in the distal tibia, a common injury site for military personnel. PURPOSE: To determine if lower limb aBMD correlates with distal total (Tt), trabecular (Tb) and cortical (Ct) vBMD in healthy, recruit-aged men and women. METHODS: Seventy-six recreationally active men (n = 43;26.4 ± 0.8 yrs.), and women (n = 33;26.2 ± 4.7 yrs.), free of any musculoskeletal conditions that could influence BMD, completed two HR-pQCT (XtremeCT; Scanco Medical) and one total body DXA (Lunar iDXA; GE Healthcare) scans. Total body DXA and non-dominant tibial HR-pQCT scans at the metaphysis (4% site) and diaphysis (30% site) were obtained. Lower leg aBMD was assessed in DXA scans with custom region of interest (ROI) analysis between the ultradistal tibia and the tibial plateau. Associations between variables were analyzed with Pearson’s correlation coefficient (r2); alpha was set at p < 0.05. RESULTS: aBMD positively correlated with Tt vBMD at the 4% site for men (r2 = 0.42; p < 0.001) and women (r2 = 0.17; p = 0.016) but only in men at the 30% site (r2 = 0.16; p = 0.008). aBMD positively correlated with Tb vBMD at the 4% site for men (r2 = 0.35; p < 0.001) and women (r2 = 0.20; p = 0.010), but not at the 30% site for either sex. aBMD was not correlated with Ct vBMD at the 4% site for either sex but was positively correlated with Ct vBMD at the 30% site in men (r2 = 0.12; p = 0.032). CONCLUSIONS: There is poor to moderate association between lower limb aBMD and tibial vBMD at both sites, with greater association in men than in women. aBMD is unlikely to provide a suitable assessment of distal tibial bone health. aBMD and tibial vBMD should, therefore, not be used interchangeably to examine the bone response to interventions or for the prediction of fracture risk. Supported by UK Ministry of Defence (WGCC 5.5.6-Task 0107).