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

This HR-pQCT study was conducted to examine bone properties of the distal tibia post-stroke and to identify clinical outcomes that were associated with these properties at this site. It was found that spasticity and gait speed were independently associated with estimated failure load in individuals with chronic stroke. PURPOSE: (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. METHODS: Sixty-four people with stroke (age, 60.8 ± 7.7 years; time since stroke, 5.7 ± 3.9 years) and 64 controls (age: 59.4 ± 7.8 years) 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. RESULTS: 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 in estimated 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). CONCLUSION: 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.

Effects of RANKL inhibition on promoting healing of bone erosion in rheumatoid arthritis using HR-pQCT: a 2-year, randomised, double-blind, placebo-controlled trial.

OBJECTIVE: To evaluate the effects of denosumab on erosion healing at 2-4 metacarpophalangeal (MCP) head as determined by high-resolution peripheral quantitative CT (HR-pQCT) in patients with rheumatoid arthritis (RA) with stable disease. METHODS: This was a randomised, placebo-controlled, double-blind study. Patients with RA with disease activity score 28 joints (DAS28) ≤5.1 were randomised (1:1) to subcutaneous denosumab 60 mg or placebo once every 6 months for 24 months. The primary outcome was erosion healing at MCP 2-4 on HR-pQCT at 12 months. The effects of denosumab on erosion and joint space parameters on HR-pQCT and radiographs, disease activity and health assessment questionnaire-disability index (HAQ-DI) were also examined. RESULTS: At 24 months, HR-pQCT images were analysed in 98 patients. One-third of the patients achieved sustained low disease activity throughout the study. At 12 months, changes in erosion parameters on HR-pQCT were similar between the two groups. At 24 months, new erosions (19% vs 9%, p=0.009) and erosion progression (18% vs 8%, p=0.019) were more common in the placebo group than the denosumab group. Erosion healing was seen in a significantly higher proportion of patients in the denosumab group (20% vs 6%, p=0.045) at 24 months. No significant changes in joint space parameters on HR-pQCT, van der Heijde-Sharp erosion score, DAS28 and HAQ-DI were observed in the two groups at 12 and 24 months. CONCLUSION: Although no differences in erosion parameters were observed at 12 months, denosumab was more efficacious than placebo in erosion repair on HR-pQCT after 24 months. TRIAL REGISTRATION NUMBER: NCT03239080.

A Critical Comparison Between Two Scanning Protocols of High-Resolution Peripheral Quantitative Computed Tomography at the Distal Radius in Adolescents.

High-resolution peripheral quantitative computed tomography (HR-pQCT) is a unique technology for assessing bone mineral density and bone microarchitecture. Currently, no universally accepted protocol for selecting the region of interest (ROI) at the distal radius has been established for growing subjects. This study aimed (1) to investigate the differences in HR-pQCT measurements of 2 different ROI protocols applied to the distal radius of healthy adolescents and (2) to identify the least common area of ROI (the least common ROI) between the protocols. Twenty-six boys and 26 girls aged between 13 and 16 yr old were recruited. Nondominant distal radius was scanned by 2 HR-pQCT protocols, namely, the "5-mm protocol," where the distal end of ROI started at 5 mm proximal to a reference line, and the "4% protocol," where the ROI started at 4% of the ulnar length proximal to another reference line. The least common ROI between the 2 protocols was identified and the slice numbering within the common ROI was determined. Bland-Altman plots were used to check the agreement of the least common ROIs between the 2 protocols. Paired t-test and Wilcoxon signed-rank test were used for analysis. In boys, significant differences between protocols were found in most parameters with the maximum difference observed in the cortical area (25.0%, p < 0.001). In girls, differences were observed only for total volumetric bone mineral density (3.6%, p = 0.032). The number of slices in the least common ROI was 66 (60.0%) and 57 (51.8%) in boys and girls, respectively. Good agreements on all HR-pQCT parameters from the least common ROI between the 2 protocols were found. Significant differences in bone parameters were noted between the 2 protocols. When comparing the 2 protocols, observed gender differences could reflect the differences in skeletal growth at the peripubertal period between genders. Least common ROI could be useful for cross-center comparisons and when merging datasets from different centers.

The Validity of Patient-Reported Outcome Measures of Quality of Life in Palliative Care: A Systematic Review.

Importance: A recent systematic review and meta-analysis found that palliative care was not associated with improvement in quality of life (QOL) in terminal noncancer illness. Among potential reasons for a null effect, it is unclear if patient-reported outcome measures (PROMs) measuring QOL were derived or validated among populations with advanced life-limiting illness (ALLI). Objective: To systematically review the derivation and validation of QOL PROMs from a recent meta-analysis of randomized controlled trials (RCT) of palliative care interventions in people with terminal noncancer illness. Evidence Review: EMBASE, MEDLINE, and PsycINFO were searched from inception to January 8, 2023 for primary validation studies of QOL PROMs in populations with ALLI, defined as adults with a progressive terminal condition and an estimated median survival of less than or equal to one year. The primary outcome was the proportion of PROMs that were derived or validated in ≥1 ALLI population. Findings: Twenty-one unique studies of derivation (n = 13) and validation (n = 11, 3 studies evaluated both) provided data on 9657 participants (mean age 63 years, 50% female) across 15 unique QOL PROMs and subscales. Among studies of validation, 9 were in people with cancer (n = 2289, n = 5 PROMs), 1 in neurodegenerative disease (n = 23, n = 1 PROM), and 1 with mixed diseases (n = 248, n = 1 PROM). Across 15 QOL PROMs and subscales, 47% (n = 7) were derived or validated in an ALLI population. The majority of these seven PROMs were exclusively derived or validated among people with cancer (57%, n = 4). QOL PROMs such as Quality of Life at End of Life, EuroQoL-5 Dimension 5-level, and 36-item Short Form Survey demonstrated validity in more than one terminal noncancer illness. Conclusions: Most QOL PROMs that measured the effect of palliative care on QOL in RCTs were neither derived nor validated in an ALLI population. These findings raise questions about the inferences that palliative care does not improve QOL among people with terminal noncancer illness.

Distinguishing risk of curve progression in adolescent idiopathic scoliosis with bone microarchitecture phenotyping - a 6-year longitudinal study.

Low bone mineral density and impaired bone qualities have been shown to be important prognostic factors for curve progression in Adolescent Idiopathic Scoliosis (AIS). There is no evidence-based integrative interpretation method to analyse high-resolution peripheral quantitative computed tomography (HR-pQCT) data in AIS. This study aimed to (a) utilize unsupervised machine learning to cluster bone microarchitecture phenotypes on HR-pQCT parameters in AIS girls, (b) assess the phenotypes' risk of curve progression and progression to surgical threshold at skeletal maturity (primary cohort), and (c) investigate risk of curve progression in a separate cohort of mild AIS girls whose curve severity did not reach bracing threshold at recruitment (secondary cohort). Patients were followed up prospectively for 6.22 ± 0.33 years in the primary cohort (N = 101). Three bone microarchitecture phenotypes were clustered by Fuzzy C-Means at time of peripubertal peak height velocity (PHV). Phenotype-1 had normal bone characteristics. Phenotype-2 was characterized by low bone volume and high cortical bone density, and Phenotype-3 had low cortical and trabecular bone density and impaired trabecular microarchitecture. The difference in bone qualities amongst the phenotypes was significant at peripubertal PHV and continued to skeletal maturity. Phenotype-3 had significantly increased risk of curve progression to surgical threshold at skeletal maturity (Odd Ratios (OR) = 4.88; 95% Confidence Interval (CI): 1.03-28.63). In the secondary cohort (N = 106), both Phenotype-2 (adjusted OR = 5.39; 95%CI: 1.47-22.76) and Phenotype-3 (adjusted OR = 3.67; 95%CI: 1.05-14.29) had increased risk of curve progression ≥6° with mean follow-up of 3.03 ± 0.16 years. In conclusion, three distinct bone microarchitecture phenotypes could be clustered by unsupervised machine learning on HR-pQCT generated bone parameters at peripubertal PHV in AIS. The bone qualities reflected by these phenotypes were found to have significant differentiating risk of curve progression and progression to surgical threshold at skeletal maturity in AIS.

Adolescent Idiopathic Scoliosis (AIS) is an abnormal spinal curvature commonly presents during puberty growth. Evidence has shown that low bone mineral density and impaired bone qualities are important risk factors for curve progression in AIS. High-resolution peripheral quantitative computed tomography (HR-pQCT) has improved our understanding of bone qualities in AIS. It generates a large amount of quantitative and qualitative bone parameters from a single measurement, but the data are not easy for clinicians to interpret and analyse. This study enrolled AIS girls and used unsupervised machine learning model to analyse their HR-pQCT data at first clinic visit. The model clustered the patients into 3 bone microarchitecture phenotypes (i.e. Phenotype-1: normal, Phenotype-2: low bone volume and high cortical bone density, and Phenotype-3: low cortical and trabecular bone density and impaired trabecular microarchitecture). They were longitudinally followed up for 6 years until skeletal maturity. We observed the three phenotypes were persistent, and Phenotype-3 had a significantly increased risk of curve progression to severity that requires invasive spinal surgery (Odds Ratio = 4.88, P = 0.029). The difference in bone qualities reflected by these 3 distinct phenotypes could aid clinicians to differentiate risk of curve progression and surgery at early stages of AIS.

Factors influencing nursing professionals' adherence to facial protective equipment usage: A comprehensive review.

BACKGROUND: Facial protective equipment (FPE) adherence is necessary for the health and safety of nursing professionals. This review was conducted to synthesize predisposing, enabling, and reinforcing factors that influence FPE adherence, and thus inform efforts to promote adherence. METHODS: Articles were collected using Cumulated Index to Nursing and Allied Health Literature and MEDLINE and screened for inclusion. Included articles were original studies focused on FPE adherence by nurses to prevent respiratory infection which contained occupation-specific data from at least 10 individuals and were published in English between January 2005 and February 2022. RESULTS: Thirty articles were included, 21 of which reported adherence rates. Adherence ranged from 33% to 100% for respiratory protection and 22% to 100% for eye protection. Predisposing demographic factors influencing adherence included tenure and occupation, while modifiable predisposing factors included knowledge and perception of FPE, infection transmission, and risk. Enabling factors included geography, care settings, and FPE availability. Reinforcing factors included organizational support for health and safety, clear policies, and training. CONCLUSIONS: The identified demographic factors suggest populations that may benefit from targeted interventions, while modifiable factors suggest opportunities to enhance education as well as operational processes and supports. Interventions that target these areas have the potential to promote adherence and thereby improve the occupational safety of nurses.

Is 911 The Answer? A Retrospective Review of Emergency Medical Services Use by Home Care Providers.

With the Ontario healthcare system under strain the use of resources-particularly emergency medical services (EMS) is an increasing focus. Recent work has identified long-term care facilities as high users of EMS despite access to health-related support outside of the hospital. However, such insights are not available for home care. A retrospective review of administrative records of EMS calls drawn from over 6 million visits by home care providers found relatively low call rates: 8.4 calls per 100 000 personal support visits, 4.1 calls per 100 000 for rehabilitation providers, and 0.9 calls per 100 000 for nurses. The majority (85%) of calls resulted in transport to the hospital; the notable exception was fall-related events, and of these falls, a third (32%) were treated at home. Classification of reported physical symptoms suggests opportunities for leveraging in-home clinical specialists to avoid hospital transport where possible and preserve EMS capacity to respond to the most urgent and severe events.

Investigation on the site of coronal deformities in Hallux valgus.

Hallux valgus (HV) is a common foot deformity that is more prevalent in females, characterised by abnormal adduction of the first metatarsal (MT) and valgus deviation of the phalanx on the transverse plane. Increasing evidence indicates that HV is more than a 2D deformity but a 3D one with rotational malalignment. Pronation deformity is seen during clinical examination for HV patients, but the exact origin of this rotational deformity is still unknown. Some attribute it to first tarsometatarsal (TMT) joint rotation, while others attribute it to intra-metatarsal bony torsion. In addition, the correlation between the rotational and transverse plane deformity is inconclusive. Identifying the origin of the rotational deformity will help surgeons choose the optimal surgical procedure while also enhancing our understanding of the pathophysiology of HV. This study aims to (1) develop an objective method for measuring the first MT torsion and first TMT joint rotation; (2) investigate the exact location of the coronal deformity in HV; (3) investigate the relationship between the severity of deformity on the transverse and coronal planes as well as the correlation between deformity severity and foot function/symptoms in HV. Age-matched females with and without HV were recruited at the Foot and Ankle Clinic of the Department of Orthopaedics and Traumatology. Computed tomography was conducted for all subjects with additional weight-bearing dorsal-plantar X-ray examination for HV subjects. Demographic information of all subjects was recorded, with symptoms and functions related to HV evaluated. The intra-class correlation was used to explore the relationship between deformities on different planes and the deformity severity and functional outcomes, respectively. An Independent t-test was used to compare joint rotation and bone torsion degrees. TMT joint rotation is significantly correlated with foot function. HV patients had more TMT joint rotation but not MT torsion compared to normal controls. No relationship was found between the coronal rotation and the 1,2-intermetatarsal angle (IMA) or Hallux valgus angle (HVA) on the transverse plane. Our results indicate that coronal deformities in HV may originate from TMT joint rotation. In addition, the severity of the TMT joint coronal rotation correlates with worse foot function; thus, multi-plane assessment and examination will be necessary for more precise surgical correction.

A novel visceral adiposity index predicts bone loss in female early rheumatoid arthritis patients detected by HR-pQCT.

The purpose of this prospective study is to compare the Chinese visceral adiposity index (CVAI) between early rheumatoid arthritis (ERA) patients and healthy controls; and to assess the relationship between CVAI and the bone microstructure using high-resolution peripheral quantitative computed tomography (HR-pQCT) in ERA patients. 104 female ERA and 100 age-, gender- and BMI-matched healthy controls were recruited for the comparison of CVAI. All ERA patients were prospectively followed for 1 year. HR-pQCT scan of the distal radius, tibia and second metacarpal head were performed at baseline and after one-year. ERA patients were divided into two sub-groups according to the median CVAI value (65.73) (low CVAI and high CVAI groups). CVAI in the ERA group was significantly higher than the controls group (p = 0.01). At baseline, the high CVAI group had a higher ESR level (p = 0.004) while the cortical volumetric bone mineral density (vBMD) was lower (at both the distal radius and tibia, all p < 0.05) compared to the low CVAI group. Linear regression analysis revealed that a higher baseline CVAI was an independent predictor of a lower cortical vBMD at month 12 (distal radius: B = - 0.626, p = 0.022, 95%CI - 1.914 to - 0.153; tibia: B = - 0.394, p = 0.003, 95%CI - 1.366 to - 0.290); and a greater reduction in trabecular vBMD (tibia: B = 0.444, p = 0.001, 95%CI 0.018-0.063; distal radius: B = 0.356, p = 0.008, 95%CI 0.403-0.063). In summary, CVAI is an independent predictor of trabecular bone loss in female patients with ERA, which may be augmented by a chronic inflammatory state in patients with visceral dysfunction of fat metabolism.Trial registration: http://Clinicaltrial.gov no: NCT01768923, 16/01/2013.

Role of inflammatory burden and treatment on joint space width in psoriatic arthritis-a high-resolution peripheral quantitative computed tomography study.

BACKGROUND: To investigate the relationship between disease-related parameters and joint space width (JSW) on high-resolution peripheral quantitative computed tomography (HR-pQCT) in psoriatic arthritis (PsA) patients. METHODS: PsA patients who underwent HR-pQCT examination of the second to fourth metacarpophalangeal joint (MCPJ 2-4) were recruited in this cross-sectional study. The joint space metrics included joint space volume (JSV), mean, minimum, and maximum JSW, JSW asymmetry, and distribution. Correlation analysis and multivariable linear regression models were used to determine the association between disease-related variables and JSW. RESULTS: Sixty-seven patients [37 (55.2%) males; median (IQR) age: 57.0 (53.0, 63.0); median disease duration: 21 (16, 28) years] were included in this analysis. Multivariable linear regression analysis demonstrated that males had larger JSV (MCPJ 2-4), mean (MCPJ 4), and maximum JSW (MCPJ 3). Longer disease duration (MCPJ 2-3) and higher ESR values (MCPJ 3) were negatively associated with mean and maximum JSW, while higher damage joint count was negatively associated with mean and minimum JSW (MCPJ 2). Use of conventional synthetic disease-modifying anti-rheumatic drugs (csDMARDs) was negatively associated with minimum JSW (MCPJ 3) while use of biologic DMARDs (bDMARDs) was positively associated with minimum JSW (MCPJ 2). CONCLUSION: Higher inflammatory burden as reflected by longer disease duration, higher ESR levels, and damage joint count was negatively associated with mean, maximum, and minimum JSW, while suppression of inflammation using bDMARDs seems to limit the decline in JSW.

More Prevalent and Severe Low Bone-Mineral Density in Boys with Severe Adolescent Idiopathic Scoliosis Than Girls: A Retrospective Study of 798 Surgical Patients.

INTRODUCTION: A total of 0.1-0.8% of AIS patients progress to severe stages without clear mechanisms, and AIS girls are more prone to curve progression than boys. Recent studies suggest that AIS girls have systemic and persistent low bone-mineral density (BMD), which has been shown to be a significant prognostic factor of curve progression in AIS. The present study aimed to (a) investigate the prevalence of low BMD in patients with severe AIS and (b) assess the sexual dimorphism and independent risk factors of low BMD in severe AIS patients. MATERIALS AND METHODS: A total of 798 patients (140 boys vs. 658 girls) with AIS who reached surgical threshold (Cobb ≥ 40°) were recruited. BMD were assessed using BMD Z-scores from dual-energy X-ray absorptiometry (DXA). Demographic, clinical, and laboratory values of the subjects were collected from their medical records. Logistic regression analysis was performed to identify independent risk factors of low BMD. RESULTS: The overall prevalence of BMD Z-score ≤ -2 and ≤ -1 were 8.1% and 37.5%, respectively. AIS boys had significantly lower BMD Z-scores (-1.2 ± 0.96 vs. -0.57 ± 0.92) and higher prevalence of low BMD (Z-score ≤ -2: 22.1% vs. 5.2%, p < 0.001; Z-score ≤ -1: 59.3% vs. 32.8%, p < 0.001) than girls. Sex, BMI, serum alkaline phosphatase, and potassium were independent factors of low BMD in the severe AIS patients. CONCLUSIONS: The present large cohort of surgical AIS patients revealed that low BMD is more prevalent and severe in boys than in girls with severe curves. Low BMD may serve as a more valuable predictive factor for curve progression to the surgical threshold in boys than girls with AIS.

Handgrip strength assessment at baseline in addition to bone parameters could potentially predict the risk of curve progression in adolescent idiopathic scoliosis.

Introduction: Adolescent idiopathic scoliosis (AIS) is characterized by deranged bone and muscle qualities, which are important prognostic factors for curve progression. This retrospective case-control study aims to investigate whether the baseline muscle parameters, in addition to the bone parameters, could predict curve progression in AIS. Methods: The study included a cohort of 126 female patients diagnosed with AIS who were between the ages of 12 and 14 years old at their initial clinical visit. These patients were longitudinally followed up every 6 months (average 4.08 years) until they reached skeletal maturity. The records of these patients were thoroughly reviewed as part of the study. The participants were categorized into two sub-groups: the progressive AIS group (increase in Cobb angle of ≥6°) and the stable AIS group (increase in Cobb angle <6°). Clinical and radiological assessments were conducted on each group. Results: Cobb angle increase of ≥6° was observed in 44 AIS patients (34.9%) prior to skeletal maturity. A progressive AIS was associated with decreased skeletal maturity and weight, lower trunk lean mass (5.7%, p = 0.027) and arm lean mass (8.9%, p < 0.050), weaker dominant handgrip strength (8.8%, p = 0.027), deranged cortical compartment [lower volumetric bone mineral density (vBMD) by 6.5%, p = 0.002], and lower bone mechanical properties [stiffness and estimated failure load lowered by 13.2% (p = 0.005) and 12.5% (p = 0.004)]. The best cut-off threshold of maximum dominant handgrip strength is 19.75 kg for distinguishing progressive AIS from stable AIS (75% sensitivity and 52.4% specificity, p = 0.011). Discussion: Patients with progressive AIS had poorer muscle and bone parameters than patients with stable AIS. The implementation of a cut-off threshold in the baseline dominant handgrip strength could potentially be used as an additional predictor, in addition to bone parameters, for identifying individuals with AIS who are at higher risk of experiencing curve progression.

Bone density and microarchitecture: relationship between hand, peripheral, and axial skeletal sites assessed by HR-pQCT and DXA in rheumatoid arthritis.

We assessed the relationship of bone density and microarchitecture between hand, peripheral, and axial skeletal sites using high-resolution peripheral quantitative computed tomography (HR-pQCT) and dual-energy X-ray absorptiometry (DXA) in patients with rheumatoid arthritis (RA) and which factors influence these parameters. This was a cross-sectional study of 100 female patients (53.4 ± 9.3 years) with RA. HR-pQCT scans at distal radius and the second metacarpal head were performed to assess cortical and trabecular volumetric bone mineral density (vBMD) and microarchitecture. DXA scans at the hip, lumbar spine, and ultradistal radius were performed to assess areal BMD. There was significant correlation in vBMD and microarchitectural parameters between the second metacarpal head and distal radius (r = 0.201-0.628). Areal BMD at the axial skeleton was moderately associated with vBMD at the peripheral sites (r = 0.354-0.558). Factors related to disease severity/chronicity significantly correlated with vBMD and microarchitecture at the distal radius and the second metacarpal head. Factors related to disease activity were more likely to correlate with vBMD and microarchitecture at the second metacarpal head but not those at the distal radius. HR-pQCT is a promising technique that is capable of providing detailed quantitative assessment of disease-associated periarticular bone loss at both cortical and trabecular bone compartments in patients with RA. Future longitudinal studies will be needed to investigate whether assessment by HR-pQCT can be used as a marker of disease activity and a predictor of disease progression in RA.

HR-pQCT for the Evaluation of Muscle Quality and Intramuscular Fat Infiltration in Ageing Skeletal Muscle.

Myosteatosis is the infiltration of fat in skeletal muscle during the onset of sarcopenia. The quantification of intramuscular adipose tissue (IMAT) can be a feasible imaging modality for the clinical assessment of myosteatosis, important for the early identification of sarcopenia patients and timely intervention decisions. There is currently no standardized method or consensus for such an application. The aim of this study was to develop a method for the detection and analysis of IMAT in clinical HR-pQCT images of the distal tibia to evaluate skeletal muscle during the ageing process, validated with animal and clinical experimentation. A pre-clinical model of ovariectomized (OVX) rats with known intramuscular fat infiltration was used, where gastrocnemii were scanned by micro-computed tomography (micro-CT) at an 8.4 µm isotropic voxel size, and the images were analyzed using our modified IMAT analysis protocol. IMAT, muscle density (MD), and muscle volume (MV) were compared with SHAM controls validated with Oil-red-O (ORO) staining. Furthermore, the segmentation and IMAT evaluation method was applied to 30 human subjects at ages from 18 to 81 (mean = 47.3 ± 19.2). Muscle-related parameters were analyzed with functional outcomes. In the animal model, the micro-CT adipose tissue-related parameter of IMAT% segmented at −600 HU to 100 HU was shown to strongly associate with the ORO-positively stained area (r = 0.898, p = 0.002). For the human subjects, at an adjusted threshold of −600 to −20 HU, moderate positive correlations were found between MV and MD (r = 0.642, p < 0.001), and between MV and IMAT volume (r = 0.618, p < 0.01). Moderate negative correlations were detected between MD and IMAT% (r = −0.640, p < 0.001). Strong and moderate associations were found between age and MD (r = −0.763, p < 0.01), and age and IMAT (r = 0.559, p < 0.01). There was also a strong correlation between IMAT% and chair rise time (r = 0.671, p < 0.01). The proposed HR-pQCT evaluation protocol for intramuscular adipose-tissue produced MD and IMAT results that were associated with age and physical performance measures, and were of good predictive value for the progression of myosteatosis or sarcopenia. The protocol was also validated on animal skeletal muscle samples that showed a good representation of histological lipid content with positive correlations, further supporting the clinical application for the rapid evaluation of muscle quality and objective quantification of skeletal muscle at the peripheral for sarcopenia assessment.

Bone Geometry, Density, Microstructure, and Biomechanical Properties in the Distal Tibia in Patients With Primary Hypertrophic Osteoarthropathy Assessed by Second-Generation High-Resolution Peripheral Quantitative Computed Tomography.

Periosteosis refers to pathological woven bone formation beneath the cortical bone of the long bones. It is an imaging hallmark of primary hypertrophic osteoarthropathy (PHO) and also considered as one of the major diagnostic criteria of PHO patients. Up to date, detailed information on bone quality changes in long bones of PHO patients is still missing. This study aimed to evaluate bone microarchitecture and bone strength in PHO patients by using high-resolution peripheral quantitative computed tomography (HR-pQCT). The study comprised 20 male PHO patients with the average age of 27.0 years and 20 age- and sex-matched healthy controls. The areal bone mineral density (aBMD) was assessed at the lumbar spine (L1 -L4 ) and hip (total hip and femoral neck) by dual-energy X-ray absorptiometry (DXA). Bone geometry, volumetric bone mineral density (vBMD), and microstructure parameters at the distal tibia were evaluated by using HR-pQCT. Bone strength was evaluated by finite element analysis (FEA) based on HR-pQCT screening at distal tibia. Urinary prostaglandin E2 (PGE2 ), serum phosphatase (ALP), beta-C-telopeptides of type I collagen (ß-CTX), soluble receptor activator of nuclear factor-κB ligand (sRANKL), osteoprotegerin (OPG), and neuronal calcitonin gene-related peptide (CGRP) were investigated. As compared with healthy controls, PHO patients had larger bone cross-sectional areas; lower total, trabecular, and cortical vBMD; compromised bone microstructures with more porous cortices, thinned trabeculae, reduced trabecular connectivity, and relatively more significant resorption of rod-like trabeculae at distal tibia. The apparent Young's modulus was significantly lower in PHO patients. The concentration of PGE2 , biomarkers of bone resorption (ß-CTX and sRANKL/OPG ratio), and the neuropeptide CGRP were higher in PHO patients versus healthy controls. PGE2 level correlated negatively with vBMD and estimated bone strength and positively with bone geometry at distal tibia. The present HR-pQCT study is the first one illustrating the microarchitecture and bone strength features in long bones. © 2021 American Society for Bone and Mineral Research (ASBMR).

Muscle plays a more superior role than fat in bone homeostasis: A cross-sectional study of old Asian people.

Objectives: The aim of this study was to discover the role of fat and muscle in bone structures, as well as the relationship between obesity and sarcopenia on age-related osteoporosis. Methods: A total of 400 participants (65.0 ± 8.2 years old, 42.3% women) were recruited. Fat, muscle, bone parameters, basic demographics, medical history, physical performance and activity, and calcium intake of participants were obtained from datasets. The diagnosis of osteoporosis, sarcopenia, and obesity was based on current recommendations. Pearson correlation, non-linear regression models, and decision tree analyses were performed to study the relationship between fat, muscle, and bone. Logistic regression analyses were used to explore the risk of osteoporosis in old people with obesity or sarcopenia via Model 1 (unadjusted) and Model 2 (adjusted by age, physical activity, and calcium intake). Results: Correlation analysis showed that limb muscle mass and index, and age were best related to bone mineral density (BMD) (|r| = 0.386-0.632, p < 0.001). On the contrary, body mass index (BMI) and increased body fat percentage (BF%) were harmful for bone health. An increase of BMI and fat mass index slowed the increase of BMD in the spine, while skeletal muscle mass index accelerated the increase. People with sarcopenia had low muscle mass and strength. When separating subjects into sarcopenia and non-sarcopenia status, sarcopenia was independently related to higher risks of osteoporosis in both models (OR > 1, p < 0.05). BMI-defined obesity in Model 1 as well as BF%-defined obesity in both models did not reduce the risk of osteoporosis in both models (p > 0.05). The decision tree classification (85% accuracy) showed that greater body weight and larger lower limb muscle performance were negatively related to osteoporosis, while fat mass and percentage did not play roles in this prediction. Conclusion: Low muscle mass and function were harmful to bone health. Obesity defined by both BMI and BF% had limited protective roles in osteoporosis. The benefits for bone from increased muscle mass and function play a more superior role than increased fat mass in old people. Sarcopenia prevention and treatment instead of controlling obesity should be recommended as an approach to reduce the risks of age-related osteoporosis and fragility fracture for elderly people.

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

Volumetric 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. INTRODUCTION: Although 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). METHODS: This 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. RESULTS: Women 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. CONCLUSION: Tb.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.

Determinants of estimated failure load in the distal radius after stroke: An HR-pQCT study.

Bone health is often compromised after stroke and the distal radius is a common site of fragility fractures. The macro- and mircoproperties of bone tissue after stroke and their clinical correlates are understudied. The objectives of the study were to use High-Resolution peripheral Quantitative Computed Tomography (HR-pQCT) to investigate the bone properties at the distal radius, and to identify the correlates of estimated failure load for the distal radius in people with chronic stroke. This was a cross-sectional study of 64 people with stroke (age: 60.8 ± 7.7 years, stroke duration: 5.7 ± 3.9 years) and 64 age- and sex-matched controls. Bilateral bone structural, densitometric, geometric and strength parameters of the distal radius were measured using HR-pQCT. The architecture, stiffness and echo intensity of the bilateral biceps brachii muscle and brachial artery blood flow were evaluated using diagnostic ultrasound. Other outcomes included the Fugl-Meyer Motor Assessment (FMA), Motor Activity Log (MAL), and Composite Spasticity Scale (CSS). The results revealed a significant side (paretic vs non-paretic for the stroke group, non-dominant vs dominant for controls) by group (stroke vs control) interaction effect for estimated failure load, cortical area, cortical thickness, trabecular number and trabecular separation, and all volumetric density parameters. Post-hoc analysis showed percent side-to-side differences in bone outcomes were greater in the stroke group than the control group, with the exception of trabecular thickness and intracortical porosity. Among the HR-pQCT variables, percent side-to-side difference in trabecular volumetric bone mineral density contributed the most to the percent side-to-side difference in estimated failure load in the stroke group (R2 change = 0.334, ß = 1.106). Stroke-related impairments (FMA, MAL, CSS) were found to be significant determinants of the percent side-to-side difference in estimated failure load (R2 change = 0.233, ß = -0.480). This was the first study to examine bone microstructure post-stroke. We found that the paretic distal radius had compromised bone structural properties and lower estimated failure load compared to the non-paretic side. Motor impairment was a determinant of estimated bone strength at the distal radius and may be a potential intervention target for improving bone health post-stroke.

Diagnosis of sarcopenia by evaluating skeletal muscle mass by adjusted bioimpedance analysis validated with dual-energy X-ray absorptiometry.

BACKGROUND: This study aimed to adjust and cross-validate skeletal muscle mass measurements between bioimpedance analysis (BIA) and dual-energy X-ray absorptiometry (DXA) for the screening of sarcopenia in the community and to estimate the prevalence of sarcopenia in Hong Kong. METHODS: Screening of sarcopenia was provided to community-dwelling older adults. Appendicular skeletal muscle mass (ASM) was evaluated by BIA (InBody 120 or 720) and/or DXA. Handgrip strength and/or gait speed were assessed. Diagnosis of sarcopenia was based on the 2019 revised Asian Working Group for Sarcopenia cut-offs. Agreement analysis was performed to cross-validate ASM measurements by BIA and DXA. Multiple regression was used to explore contribution of measured parameters in predicting DXA ASM from BIA. RESULTS: A total of 1587 participants (age = 72 ± 12 years) were recruited; 1065 participants were screened by BIA (InBody 120) with 18 followed up by DXA, while the remaining 522 participants were assessed by the BIA (InBody 720) and DXA. The appendicular skeletal muscle mass index (ASMI) evaluated by BIA showed a mean difference of 2.89 ± 0.38 kg/m2 (InBody 120) and 2.97 ± 0.45 kg/m2 (InBody 720) against DXA gold standard. A significant overestimation of muscle mass was measured by BIA compared with DXA (P < 0.005). BIA data were adjusted using prediction equation and mean difference reduced to -0.02 ± 0.31 kg/m2 in cross-validation. Prevalence of sarcopenia in older adults ≥65 ranged from 39.4% (based on ASMI by DXA) to 40.8% (based on predicted DXA ASMI from BIA). Low ASMI by DXA was found in 68.5% of the older adults screened. The percentage of older adults exhibited low handgrip strength ranged from 31.3% to 56%, while 49% showed low gait speed. CONCLUSIONS: Bioimpedance analysis was found to overestimate skeletal muscle mass compared with DXA. With adjustment equations, BIA can be used as a quick and reliable tool for screening sarcopenia in community and clinical settings with limited access to better options.

Best Performance Parameters of HR-pQCT to Predict Fragility Fracture: Systematic Review and Meta-Analysis.

Osteoporosis is a systemic skeletal disease characterized by low bone mass and bone structural deterioration that may result in fragility fractures. Use of bone imaging modalities to accurately predict fragility fractures is always an important issue, yet the current gold standard of dual-energy X-ray absorptiometry (DXA) for diagnosis of osteoporosis cannot fully satisfy this purpose. The latest high-resolution peripheral quantitative computed tomography (HR-pQCT) is a three-dimensional (3D) imaging device to measure not only volumetric bone density, but also the bone microarchitecture in a noninvasive manner that may provide a better fracture prediction power. This systematic review and meta-analysis was designed to investigate which HR-pQCT parameters at the distal radius and/or distal tibia could best predict fragility fractures. A systematic literature search was conducted in Embase, PubMed, and Web of Science with relevant keywords by two independent reviewers. Original clinical studies using HR-pQCT to predict fragility fractures with available full text in English were included. Information was extracted from the included studies for further review. In total, 25 articles were included for the systematic review, and 16 articles for meta-analysis. HR-pQCT was shown to significantly predict incident fractures and/or major osteoporotic fractures (MOFs). Of all the HR-pQCT parameters, our meta-analysis revealed that cortical volumetric bone mineral density (Ct.vBMD), trabecular thickness (Tb.Th), and stiffness were better predictors. Meanwhile, HR-pQCT parameters indicated better performance in predicting MOFs than incident fractures. Between the two standard measurement sites of HR-pQCT, the non-weight-bearing distal radius was a more preferable site than distal tibia for fracture prediction. Furthermore, most of the included studies were white-based, whereas very few studies were from Asia or South America. These regions should build up their densitometric databases and conduct related prediction studies. It is expected that HR-pQCT can be used widely for the diagnosis of osteoporosis and prediction of future fragility fractures. © 2021 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).