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STUDY PURPOSE: Morphometric methods categorize potential osteoporotic vertebral fractures (OVF) on the basis of loss of vertebral height. A particular example is the widely used semiquantitative morphometric tool proposed by Genant (GSQ). A newer morphologic algorithm-based qualitative (mABQ) tool focuses on vertebral end-plate damage in recognizing OVF. We used data from both sexes in the Canadian Multicentre Osteoporosis Study (CaMos) to compare the 2 methods in identifying OVF at baseline and during 10 years of follow-up. MATERIALS AND METHODS: We obtained lateral thoracic and lumbar spinal radiographs (T4-L4) 3 times, at 5-year intervals, in 828 participants of the population-based CaMos. Logistic regressions were used to study the association of 10-year changes in bone mineral density (BMD) with incident fractures. RESULTS: At baseline, 161 participants had grade 1 and 32 had grade 2 GSQ OVF; over the next 10 years, only 9 of these participants had sustained incident GSQ OVF. Contrastingly, 21 participants at baseline had grade 1 and 48 grade 2 mABQ events; over the next 10 years, 79 subjects experienced incident grade 1 or grade 2 mABQ events. Thus, incident grades 1 and 2 morphologic fractures were 8 times more common than morphometric deformities alone. Each 10-year decrease of 0.01 g/cm2 in total hip BMD was associated with a 4.1% (95% CI: 0.7-7.3) higher odds of having an incident vertebral fracture. CONCLUSIONS: This analysis further suggests that morphometric deformities and morphologic fractures constitute distinct entities; morphologic fractures conform more closely to the expected epidemiology of OVF.
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Fraturas por Osteoporose/diagnóstico por imagem , Radiografia/métodos , Fraturas da Coluna Vertebral/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Canadá , Estudos de Coortes , Progressão da Doença , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Radiologia , Coluna Vertebral/diagnóstico por imagemRESUMO
Musculoskeletal science has developed many overlapping branches, necessitating specialists from 1 area of focus to often require the expertise in others. In terms of imaging, this means obtaining a comprehensive illustration of bone, muscle, and fat tissues. There is currently a lack of a reliable resource for end users to learn about these tissues' imaging and quantification techniques together. An improved understanding of these tissues has been an important progression toward better prediction of disease outcomes and better elucidation of their interaction with frailty, aging, and metabolic disorders. Over the last decade, there have been major advances into the image acquisition and segmentation of bone, muscle, and fat features using computed tomography (CT), magnetic resonance imaging (MRI), and peripheral modules of these systems. Dedicated peripheral quantitative musculoskeletal imaging systems have paved the way for mobile research units, lower cost clinical research facilities, and improved resolution per unit cost paid. The purpose of this review was to detail the segmentation techniques available for each of these peripheral CT and MRI modalities and to describe advances in segmentation methods as applied to study longitudinal changes and treatment-related dynamics. Although the peripheral CT units described herein have established feasible standardized protocols that users have adopted globally, there remain challenges in standardizing MRI protocols for bone and muscle imaging.
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Osso e Ossos/diagnóstico por imagem , Músculo Esquelético/diagnóstico por imagem , Tecido Adiposo/anatomia & histologia , Tecido Adiposo/diagnóstico por imagem , Osso e Ossos/anatomia & histologia , Humanos , Imageamento por Ressonância Magnética/métodos , Músculo Esquelético/anatomia & histologia , Tomografia Computadorizada por Raios X/métodosRESUMO
Lower peripheral quantitative computed tomography (pQCT)-derived leg muscle density has been associated with fragility fractures in postmenopausal women. Limb movement during image acquisition may result in motion streaks in muscle that could dilute this relationship. This cross-sectional study examined a subset of women from the Canadian Multicentre Osteoporosis Study. pQCT leg scans were qualitatively graded (1-5) for motion severity. Muscle and motion streak were segmented using semi-automated (watershed) and fully automated (threshold-based) methods, computing area, and density. Binary logistic regression evaluated odds ratios (ORs) for fragility or all-cause fractures related to each of these measures with covariate adjustment. Among the 223 women examined (mean age: 72.7 ± 7.1 years, body mass index: 26.30 ± 4.97 kg/m2), muscle density was significantly lower after removing motion (p < 0.001) for both methods. Motion streak areas segmented using the semi-automated method correlated better with visual motion grades (rho = 0.90, p < 0.01) compared to the fully automated method (rho = 0.65, p < 0.01). Although the analysis-reanalysis precision of motion streak area segmentation using the semi-automated method is above 5% error (6.44%), motion-corrected muscle density measures remained well within 2% analytical error. The effect of motion-correction on strengthening the association between muscle density and fragility fractures was significant when motion grade was ≥3 (p interaction <0.05). This observation was most dramatic for the semi-automated algorithm (OR: 1.62 [0.82,3.17] before to 2.19 [1.05,4.59] after correction). Although muscle density showed an overall association with all-cause fractures (OR: 1.49 [1.05,2.12]), the effect of motion-correction was again, most impactful within individuals with scans showing grade 3 or above motion. Correcting for motion in pQCT leg scans strengthened the relationship between muscle density and fragility fractures, particularly in scans with motion grades of 3 or above. Motion streaks are not confounders to the relationship between pQCT-derived leg muscle density and fractures, but may introduce heterogeneity in muscle density measurements, rendering associations with fractures to be weaker.
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Músculo Esquelético/diagnóstico por imagem , Fraturas por Osteoporose/epidemiologia , Intensificação de Imagem Radiográfica/métodos , Tomografia Computadorizada por Raios X/métodos , Idoso , Algoritmos , Artefatos , Estudos Transversais , Feminino , Humanos , Perna (Membro) , Movimento (Física)RESUMO
BACKGROUND: Despite knowing better how to screen older adults, understanding how frailty progression might be modified is unclear. We explored effects of modifiable and non-modifiable factors on changes in frailty in community-dwelling adults aged 50+ years who participated in the Canadian Multicentre Osteoporosis Study (CaMos). METHODS: Rates of change in frailty over 10 years were examined using the 30-item CaMos Frailty Index (CFI). Incident and prevalent low-trauma fractures were categorized by fracture site into hip, clinical vertebral and non-hip-non-vertebral fractures. Multivariable generalized estimating equation models accounted for the time of frailty assessment (baseline, 5 and 10 years), sex, age, body mass index (BMI, kg/m2), physical activity, bone mineral density, antiresorptive therapy, health-related quality of life (HRQL), cognitive status, and other factors for frailty or fractures. Multiple imputation and scenario analyses addressed bias due to attrition or missing data. RESULTS: The cohort included 5566 women (mean ± standard deviation: 66.8 ± 9.3 years) and 2187 men (66.3 ± 9.5 years) with the mean baseline CFI scores of 0.15 ± 0.11 and 0.12 ± 0.10, respectively. Incident fractures and obesity most strongly predicted frailty progression in multivariable analyses. The impact of fractures differed between the sexes. With each incident hip fracture, the adjusted mean CFI accelerated per 5 years by 0.07 in women (95% confidence interval [CI]: 0.03 to 0.11) and by 0.12 in men (95% CI: 0.08 to 0.16). An incident vertebral fracture increased frailty in women (0.05, 95% CI: 0.02 to 0.08) but not in men (0.01, 95% CI: -0.07 to 0.09). Irrespective of sex and prevalent fractures, baseline obesity was associated with faster frailty progression: a 5-year increase in the adjusted mean CFI ranged from 0.01 in overweight (BMI: 25.0 to 29.9 kg/m2) to 0.10 in obese individuals (BMI: ≥ 40 kg/m2). Greater physical activity and better HRQL decreased frailty over time. The results remained robust in scenario analyses. CONCLUSIONS: Older women and men with new vertebral fractures, hip fractures or obesity represent high-risk groups that should be considered for frailty interventions.
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Progressão da Doença , Fragilidade/epidemiologia , Obesidade/epidemiologia , Fraturas por Osteoporose/epidemiologia , Idoso , Índice de Massa Corporal , Densidade Óssea/fisiologia , Canadá/epidemiologia , Estudos de Coortes , Feminino , Fragilidade/diagnóstico , Fraturas do Quadril/diagnóstico , Fraturas do Quadril/epidemiologia , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Obesidade/diagnóstico , Osteoporose/diagnóstico , Osteoporose/epidemiologia , Fraturas por Osteoporose/diagnóstico , Fraturas da Coluna Vertebral/diagnóstico , Fraturas da Coluna Vertebral/epidemiologiaRESUMO
PURPOSE OF REVIEW: Bone and muscle peripheral imaging technologies are reviewed for their association with fractures and frailty. A narrative systematized review was conducted for bone and muscle parameters from each imaging technique. In addition, meta-analyses were performed across all bone quality parameters. RECENT FINDINGS: The current body of evidence for bone quality's association with fractures is strong for (high-resolution) peripheral quantitative computed tomography (pQCT), with trabecular separation (Tb.Sp) and integral volumetric bone mineral density (vBMD) reporting consistently large associations with various fracture types across studies. Muscle has recently been linked to fractures and frailty, but the quality of evidence remains weaker from studies of small sample sizes. It is increasingly apparent that musculoskeletal tissues have a complex relationship with interrelated clinical endpoints such as fractures and frailty. Future studies must concurrently address these relationships in order to decipher the relative importance of one causal pathway from another.
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Osso e Ossos/diagnóstico por imagem , Osso Esponjoso/diagnóstico por imagem , Músculo Esquelético/diagnóstico por imagem , Absorciometria de Fóton , Composição Corporal , Densidade Óssea , Osso e Ossos/patologia , Humanos , Imageamento por Ressonância Magnética , Músculo Esquelético/patologia , Tamanho do Órgão , Tomografia Computadorizada por Raios XRESUMO
In peripheral quantitative computed tomography scans of the calf muscles, segmentation of muscles from subcutaneous fat is challenged by muscle fat infiltration. Threshold-based edge detection segmentation by manufacturer software fails when muscle boundaries are not smooth. This study compared the test-retest precision error for muscle-fat segmentation using the threshold-based edge detection method vs manual segmentation guided by the watershed algorithm. Three clinical populations were investigated: younger adults, older adults, and adults with spinal cord injury (SCI). The watershed segmentation method yielded lower precision error (1.18%-2.01%) and higher (p<0.001) muscle density values (70.2±9.2 mg/cm3) compared with threshold-based edge detection segmentation (1.77%-4.06% error, 67.4±10.3 mg/cm3). This was particularly true for adults with SCI (precision error improved by 1.56% and 2.64% for muscle area and density, respectively). However, both methods still provided acceptable precision with error well under 5%. Bland-Altman analyses showed that the major discrepancies between the segmentation methods were found mostly among participants with SCI where more muscle fat infiltration was present. When examining a population where fatty infiltration into muscle is expected, the watershed algorithm is recommended for muscle density and area measurement to enable the detection of smaller change effect sizes.
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Interpretação de Imagem Assistida por Computador , Músculo Esquelético/diagnóstico por imagem , Gordura Subcutânea/diagnóstico por imagem , Adulto , Algoritmos , Feminino , Humanos , Interpretação de Imagem Assistida por Computador/instrumentação , Interpretação de Imagem Assistida por Computador/métodos , Interpretação de Imagem Assistida por Computador/normas , Masculino , Pessoa de Meia-Idade , Melhoria de Qualidade , Reprodutibilidade dos Testes , Software , Tomografia Computadorizada por Raios X/métodosRESUMO
BACKGROUND: Lower levels of osteoprotegerin (OPG), the decoy receptor for receptor activator of NFκB (RANK)-ligand, have been reported among women with a BRCA1 mutation, suggesting OPG may be marker of cancer risk. Whether various reproductive, hormonal, or lifestyle factors impact OPG levels in these women is unknown. METHODS: BRCA1 mutation carriers enrolled in a longitudinal study, no history of cancer, and a serum sample for OPG quantification, were included. Exposure information was collected through self-reported questionnaire at study enrollment and every 2 years thereafter. Serum OPG levels (pg/mL) were measured using an ELISA, and generalized linear models were used to assess the associations between reproductive, hormonal, and lifestyle exposures at the time of blood collection with serum OPG. Adjusted means were estimated using the fully adjusted model. RESULTS: A total of 701 women with a median age at blood collection of 39.0 years (18.0-82.0) were included. Older age (Spearman r = 0.24; P < 0.001) and current versus never smoking (98.82 vs. 86.24 pg/mL; Pcat < 0.001) were associated with significantly higher OPG, whereas ever versus never coffee consumption was associated with significantly lower OPG (85.92 vs. 94.05 pg/mL; Pcat = 0.03). There were no other significant associations for other exposures (P ≥ 0.06). The evaluated factors accounted for 7.5% of the variability in OPG. CONCLUSIONS: OPG is minimally influenced by hormonal and lifestyle factors among BRCA1 mutation carriers. IMPACT: These findings suggest that circulating OPG levels are not impacted by non-genetic factors in high-risk women.
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Genes BRCA1 , Osteoprotegerina , Adulto , Feminino , Humanos , Proteína BRCA1/genética , Estudos Longitudinais , Osteoprotegerina/genética , FumarRESUMO
INTRODUCTION: Sarcopenia is a predictor of clinical outcomes in men with metastatic castrate-resistant prostate cancer (mCRPC); however, correlates and predictors of sarcopenia are poorly understood in this population. The aim of this study was to examine correlates and predictors of sarcopenia in men with mCRPC prior to treatment. METHODS: A secondary analysis of an observational study was performed. Participants were receiving care for mCRPC at the Princess Margaret Cancer Centre. Sarcopenia was assessed prior to treatment and was defined as the combination of low grip strength (<35.5 kg), low gait speed (<0.8 m/s), and computed tomography-derived low muscle mass or density. Participants' sociodemographic and clinical characteristics, comorbidity information, and clinically relevant blood markers were collected prior to treatment and were used to identify correlates and predictors of sarcopenia through Spearman correlations and multivariable logistic regression, respectively. RESULTS: In total, 110 men had complete data on sarcopenia measures and were included in the analysis. Sarcopenia was identified in 30 (27.3%) participants. Pre-treatment sarcopenia was moderately correlated with dependence in one or more instrumental activities of daily living (IADLs) (r=0.412), Vulnerable Elders Survey-13 (r=0.404), and a lower hemoglobin (r=0.407 per 10 g/L decrease). In adjusted logistic regression, dependence in one or more IADLs (odds ratio [OR] 4.37, 95% confidence interval [CI] 1.37-13.86, p=0.012), and a 10 g/L decrease in hemoglobin (OR 1.70, 95% CI 1.13-2.57, p=0.012) were significantly associated with sarcopenia. CONCLUSIONS: In settings where assessment of sarcopenia is not feasible, evaluation of IADLs and hemoglobin may be used to identify high-risk patients that can benefit from supportive care strategies aiming to improve muscle mass and function.
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Fracture risk increases with lower areal bone mineral density (aBMD); however, aBMD-related estimate of risk may decrease with age. This may depend on technical limitations of 2-dimensional (2D) dual energy X-ray absorptiometry (DXA) which are reduced with 3D high-resolution peripheral quantitative computed tomography (HR-pQCT). Our aim was to examine whether the predictive utility of HR-pQCT measures with fracture varies with age. We analyzed associations of HR-pQCT measures at the distal radius and distal tibia with two outcomes: incident fractures and major osteoporotic fractures. We censored follow-up time at first fracture, death, last contact or 8 years after baseline. We estimated hazard ratios (HR) and 95%CI for the association between bone traits and fracture incidence across age quintiles. Among 6835 men and women (ages 40-96) with at least one valid baseline HR-pQCT scan who were followed prospectively for a median of 48.3 months, 681 sustained fractures. After adjustment for confounders, bone parameters at both the radius and tibia were associated with higher fracture risk. The estimated HRs for fracture did not vary significantly across age quintiles for any HR-pQCT parameter measured at either the radius or tibia. In this large cohort, the homogeneity of the associations between the HR-pQCT measures and fracture risk across age groups persisted for all fractures and for major osteoporotic fractures. The patterns were similar regardless of the HR-pQCT measure, the type of fracture, or the statistical models. The stability of the associations between HR-pQCT measures and fracture over a broad age range shows that bone deficits or low volumetric density remain major determinants of fracture risk regardless of age group. The lower risk for fractures across measures of aBMD in older adults in other studies may be related to factors which interfere with DXA but not with HR-pQCT measures.
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Tomografia Computadorizada por Raios X , Humanos , Idoso , Masculino , Feminino , Estudos Prospectivos , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Fatores de Risco , Densidade Óssea , Adulto , Fraturas Ósseas/diagnóstico por imagem , Fraturas Ósseas/epidemiologia , Envelhecimento , Rádio (Anatomia)/diagnóstico por imagem , Tíbia/diagnóstico por imagem , Tíbia/patologiaRESUMO
INTRODUCTION: Sarcopenia is common in men with metastatic castrate-resistant prostate cancer (mCRPC) and has been largely assessed opportunistically through computed-tomography (CT) scans, excluding measures of muscle function. Therefore, the impact of a comprehensive assessment of sarcopenia on clinical outcomes in men with mCRPC is poorly understood. The objectives of this study were to comprehensively assess sarcopenia through CT scans and measures of muscle function and examine its impact on severe treatment toxicity, time to first emergency room (ER) visit, disease progression, and overall mortality in men initiating chemotherapy or androgen receptor-targeted axis (ARAT) therapy for mCRPC. METHODS: This was a secondary analysis of a prospective observational study of men with mCRPC at the Princess Margaret Cancer Centre between July 2015-May 2021. Participants were classified as sarcopenic if they had CT-based low muscle mass or low muscle density, a grip strength and gait speed score of <35.5kg and <0.8m/s, respectively, prior to treatment initiation. The impact of sarcopenia on severe treatment toxicity was assessed using multivariable logistic regression. Multivariable Cox regression models were used to determine the impact of sarcopenia on risk of visiting the ER, prostate-specific antigen progression, radiographic progression, and overall mortality. RESULTS: A total of 110 men (mean age: 74.6) were included in the analysis. At baseline, 30 (27.3%) were classified as sarcopenic. Sarcopenia was a significant predictor of severe toxicity (aOR = 6.26, 95%CI = 1.17-33.58, P = 0.032) and ER visits (aHR = 4.41, 95%CI = 1.26-15.43, p = 0.020) in men initiating ARAT but not in men initiating chemotherapy. Sarcopenia was also a predictor of radiographic progression (aHR = 2.39, 95%CI = 1.06-5.36, p = 0.035) and overall mortality (aHR = 2.44, 95%CI = 1.17-5.08, p = 0.018) regardless of treatment type. CONCLUSIONS: Baseline sarcopenia predicts radiographic progression and overall mortality in men with mCRPC regardless of the type of treatment and may also predict severe treatment toxicity and ER visits in men initiating ARAT.
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Neoplasias de Próstata Resistentes à Castração , Sarcopenia , Masculino , Humanos , Idoso , Sarcopenia/complicações , Neoplasias de Próstata Resistentes à Castração/complicações , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Antígeno Prostático Específico/uso terapêutico , Modelos de Riscos Proporcionais , Estudos ProspectivosRESUMO
Most fracture risk assessment tools use clinical risk factors combined with bone mineral density (BMD) to improve assessment of osteoporosis; however, stratifying fracture risk remains challenging. This study developed a fracture risk assessment tool that uses information about volumetric bone density and three-dimensional structure, obtained using high-resolution peripheral quantitative compute tomography (HR-pQCT), to provide an alternative approach for patient-specific assessment of fracture risk. Using an international prospective cohort of older adults (n = 6802) we developed a tool to predict osteoporotic fracture risk, called µFRAC. The model was constructed using random survival forests, and input predictors included HR-pQCT parameters summarizing BMD and microarchitecture alongside clinical risk factors (sex, age, height, weight, and prior adulthood fracture) and femoral neck areal BMD (FN aBMD). The performance of µFRAC was compared to the Fracture Risk Assessment Tool (FRAX) and a reference model built using FN aBMD and clinical covariates. µFRAC was predictive of osteoporotic fracture (c-index = 0.673, p < 0.001), modestly outperforming FRAX and FN aBMD models (c-index = 0.617 and 0.636, respectively). Removal of FN aBMD and all clinical risk factors, except age, from µFRAC did not significantly impact its performance when estimating 5-year and 10-year fracture risk. The performance of µFRAC improved when only major osteoporotic fractures were considered (c-index = 0.733, p < 0.001). We developed a personalized fracture risk assessment tool based on HR-pQCT that may provide an alternative approach to current clinical methods by leveraging direct measures of bone density and structure. © 2023 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).
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Fraturas por Osteoporose , Humanos , Idoso , Adulto , Fraturas por Osteoporose/diagnóstico por imagem , Estudos Prospectivos , Tomografia Computadorizada por Raios X , Densidade Óssea , Medição de RiscoRESUMO
It was hypothesized that nitric oxide (NO) and prostaglandins (PGs) play a synergistic role in modulating haemodynamic responses to angiotensin II (ANG II) in an age-dependent manner. To this end, experiments were carried out in conscious, chronically instrumented lambs aged â¼1 week (N = 9) and â¼6 weeks (N = 10) to evaluate the haemodynamic responses to ANG II, before and after treatment with the L: -arginine analogue, N-nitro-L: -arginine methyl ester (L: -NAME), as well as the cyclooxygenase inhibitor, indomethacin (INDO). Pressor and renal blood flow responses to ANG II were measured before (control) and after administration of L: -NAME (20 mg kg(-1)), following pretreatment with either vehicle (VEH) (experiment 1) or INDO (1 mg kg(-1), experiment 2). The two experiments were carried out at minimum intervals of 48 h. In both age groups, the pressor and renal vasoconstrictor responses to ANG II were augmented by pretreatment with INDO, the effects being similar at 1 and 6 weeks. The haemodynamic responses to ANG II were, however, not altered after L: -NAME following pretreatment with either VEH or INDO. These data provide new evidence that soon after birth, endogenously produced PGs, but not endogenously produced NO, balance the vasoconstrictor actions of ANG II. There is, however, no apparent interaction between PGs and NO in modulating the responses to ANG II postnatally.
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Angiotensina II/farmacologia , Hemodinâmica/efeitos dos fármacos , Óxido Nítrico/fisiologia , Prostaglandinas/fisiologia , Envelhecimento , Animais , Animais Recém-Nascidos , Pressão Sanguínea/efeitos dos fármacos , Inibidores de Ciclo-Oxigenase/farmacologia , Feminino , Indometacina/farmacologia , Rim/irrigação sanguínea , Rim/efeitos dos fármacos , Masculino , NG-Nitroarginina Metil Éster/farmacologia , Circulação Renal/efeitos dos fármacos , Carneiro Doméstico , Vasoconstrição/efeitos dos fármacosRESUMO
Prevalence of osteoporosis is more than 50% in older adults, yet current clinical methods for diagnosis that rely on areal bone mineral density (aBMD) fail to detect most individuals who have a fragility fracture. Bone fragility can manifest in different forms, and a "one-size-fits-all" approach to diagnosis and management of osteoporosis may not be suitable. High-resolution peripheral quantitative computed tomography (HR-pQCT) provides additive information by capturing information about volumetric density and microarchitecture, but interpretation is challenging because of the complex interactions between the numerous properties measured. In this study, we propose that there are common combinations of bone properties, referred to as phenotypes, that are predisposed to different levels of fracture risk. Using HR-pQCT data from a multinational cohort (n = 5873, 71% female) between 40 and 96 years of age, we employed fuzzy c-means clustering, an unsupervised machine-learning method, to identify phenotypes of bone microarchitecture. Three clusters were identified, and using partial correlation analysis of HR-pQCT parameters, we characterized the clusters as low density, low volume, and healthy bone phenotypes. Most males were associated with the healthy bone phenotype, whereas females were more often associated with the low volume or low density bone phenotypes. Each phenotype had a significantly different cumulative hazard of major osteoporotic fracture (MOF) and of any incident osteoporotic fracture (p < 0.05). After adjustment for covariates (cohort, sex, and age), the low density followed by the low volume phenotype had the highest association with MOF (hazard ratio = 2.96 and 2.35, respectively), and significant associations were maintained when additionally adjusted for femoral neck aBMD (hazard ratio = 1.69 and 1.90, respectively). Further, within each phenotype, different imaging biomarkers of fracture were identified. These findings suggest that osteoporotic fracture risk is associated with bone phenotypes that capture key features of bone deterioration that are not distinguishable by aBMD. © 2021 American Society for Bone and Mineral Research (ASBMR).
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Osteoporose , Fraturas por Osteoporose , Absorciometria de Fóton/métodos , Idoso , Densidade Óssea , Osso e Ossos/diagnóstico por imagem , Feminino , Humanos , Masculino , Osteoporose/complicações , Osteoporose/diagnóstico por imagem , Osteoporose/epidemiologia , Fraturas por Osteoporose/diagnóstico por imagem , Fraturas por Osteoporose/epidemiologia , FenótipoRESUMO
The study's purpose was to assess the effect of multiplanar reconstruction on precision of weight-bearing medial and lateral femoral cartilage (cMF, cLF) morphometry in maloriented coronal MR images. Twenty knees were scanned four times with a 1.0 Tesla extremity imager using a fat-suppressed T1-weighted three-dimensional spoiled gradient recalled echo sequence; twice with "best as" double bull's-eye orientation of the femoral condyles, and once each with 5° internal and external rotation. Multiplanar reconstruction was applied to maloriented scans to recover double bull's-eye orientation. Medial and lateral femoral cartilages were segmented and precision of bone area, cartilage volume and thickness (ThCtAB) evaluated for all scans. Test-retest precision (RMSCV%) of the double bull's-eye scans was 1.1% for total bone area and 4.1% for cartilage volume. Differences in precision between double bull's-eye and maloriented images were assessed. Higher precision errors were observed in malorientated images for all outcomes (1.7-4.8% for internally rotation scans; 1.7-4.8% for external rotation scans). Precision generally improved with multiplanar reconstruction correction (1.7-5.6% for internally rotated scans; 1.2-3.5% for external rotation scans). Precision of femoral cartilage morphometry is generally reduced when maloriented images are acquired. Multiplanar reconstruction can correct malorientated scans and recover precision losses. Measurements are affected in a rotationally and compartmentally dependent manner.
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Artefatos , Cartilagem Articular/patologia , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Osteoartrite do Joelho/patologia , Adulto , Idoso , Algoritmos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
Antiresorptive medications have been explored for treating knee osteoarthritis (OA); however, little data exist on the effects of today's more potent nitrogen-containing oral bisphosphonates on radiographic disease-progression in patients with varying disease-severity, especially those who are not overweight. The primary objective of this cohort study was to determine if the use of bisphosphonates is protective against 2-year radiographic-progression of knee OA in Osteoarthritis Initiative (OAI) participants, stratified by baseline radiographic disease status. Secondary objectives were to examine effects in non-overweight participants (body mass index [BMI] < 25 kg/m2 ) and cumulative bisphosphonate exposure effects. We identified female OAI participants aged ≥50 years and excluded those missing baseline radiograph readings, bisphosphonate use information, or all clinical questionnaire information at baseline. Participants reporting bisphosphonate use (69% alendronate) were propensity-matched 1:1 to non-bisphosphonate users and followed until first radiographic knee OA progression (1-unit increase in Kellgren and Lawrence [KL] grade) or data were censored (first missed visit or end of 2-year follow-up). Discrete-time logistic regression models estimated hazard ratios (HRs) between bisphosphonate users versus nonusers, with an interaction term for baseline KL grade (KL <2 or KL ≥2). We identified 1977 eligible women (n = 346 bisphosphonate users). Propensity-matched results indicated that bisphosphonate users with KL grade <2 were protected against progression (HRKL<2 0.53; 95% CI, 0.35 to 0.79), while bisphosphonate use was not associated with radiographic progression in those with KL grade ≥2 (HRKL≥2 1.06; 95% CI, 0.83 to 1.35). When restricting analyses to those with BMI <25 kg/m2 , effects were strengthened (HRKL<2 0.49 [95% CI, 0.26 to 0.92]; HRKL≥2 0.69 [95% CI, 0.33 to 1.26]). Duration of bisphosphonate use had no effect on progression, though sample size was limited. Bisphosphonate therapy may be protective against radiographic knee OA progression in early-stage patients, particularly those who are non-overweight, but less so for those with more advanced disease or more weight-bearing joint stress. © 2020 American Society for Bone and Mineral Research (ASBMR).
Assuntos
Osteoartrite do Joelho , Estudos de Coortes , Difosfonatos/uso terapêutico , Progressão da Doença , Feminino , Humanos , Articulação do Joelho , Osteoartrite do Joelho/diagnóstico por imagem , Osteoartrite do Joelho/tratamento farmacológico , Índice de Gravidade de DoençaRESUMO
BACKGROUND: Although areal bone mineral density (aBMD) assessed by dual-energy x-ray absorptiometry (DXA) is the clinical standard for determining fracture risk, most older adults who sustain a fracture have T scores greater than -2·5 and thus do not meet the clinical criteria for osteoporosis. Importantly, bone fragility is due to low BMD and deterioration in bone structure. We assessed whether indices of high-resolution peripheral quantitative CT (HR-pQCT) were associated with fracture risk independently of femoral neck aBMD and the Fracture Risk Assessment Tool (FRAX) score. METHODS: We assessed participants in eight cohorts from the USA (Framingham, Mayo Clinic), France (QUALYOR, STRAMBO, OFELY), Switzerland (GERICO), Canada (CaMos), and Sweden (MrOS). We used Cox proportional hazard ratios (HRs) to estimate the association between HR-pQCT bone indices (per 1 SD of deficit) and incident fracture, adjusting for age, sex, height, weight, and cohort, and then additionally for femoral neck DXA aBMD or FRAX. FINDINGS: 7254 individuals (66% women and 34% men) were assessed. Mean baseline age was 69 years (SD 9, range 40-96). Over a mean follow-up of 4·63 years (SD 2·41) years, 765 (11%) participants had incident fractures, of whom 633 (86%) had femoral neck T scores greater than -2·5. After adjustment for age, sex, cohort, height, and weight, peripheral skeleton failure load had the greatest association with risk of fracture: tibia HR 2·40 (95% CI 1·98-2·91) and radius 2·13 (1·77-2·56) per 1 SD decrease. HRs for other bone indices ranged from 1·12 (95% CI 1·03-1·23) per 1 SD increase in tibia cortical porosity to 1·58 (1·45-1·72) per 1 SD decrease in radius trabecular volumetric bone density. After further adjustment for femoral neck aBMD or FRAX score, the associations were reduced but remained significant for most bone parameters. A model including cortical volumetric bone density, trabecular number, and trabecular thickness at the distal radius and a model including these indices plus cortical area at the tibia were the best predictors of fracture. INTERPRETATION: HR-pQCT indices and failure load improved prediction of fracture beyond femoral neck aBMD or FRAX scores alone. Our findings from a large international cohort of men and women support previous reports that deficits in trabecular and cortical bone density and structure independently contribute to fracture risk. These measurements and morphological assessment of the peripheral skeleton might improve identification of people at the highest risk of fracture. FUNDING: National Institutes of Health National Institute of Arthritis Musculoskeletal and Skin Diseases.
Assuntos
Densidade Óssea , Doenças Ósseas Metabólicas/diagnóstico por imagem , Osso Esponjoso/diagnóstico por imagem , Osso Cortical/diagnóstico por imagem , Fraturas Ósseas/epidemiologia , Fraturas por Osteoporose/epidemiologia , Absorciometria de Fóton , Idoso , Idoso de 80 Anos ou mais , Doenças Ósseas Metabólicas/epidemiologia , Feminino , Colo do Fêmur/diagnóstico por imagem , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Osteoporose/diagnóstico por imagem , Osteoporose/epidemiologia , Modelos de Riscos Proporcionais , Estudos Prospectivos , Medição de Risco , Tomografia Computadorizada por Raios XRESUMO
OBJECTIVE: The purpose of this study was to develop a skeletal muscle mimic phantom compatible with quantitative computed tomography (QCT) and magnetic resonance imaging, yielding physiologically appropriate values. METHODS: Agar-based phantoms contained varying concentrations of CuCl2 and EDTA to adjust T2 relaxation time and phantom density concurrently. T2 relaxation times were quantified using a 4-mm single-slice fast spin echo sequence repeated for six serial echo times at 937-µm resolution. T2 relaxation maps were generated using the Levenberg-Marquardt equation. A peripheral QCT scanner measured linear attenuation coefficients of phantoms, which were converted to density (mg/cm3) values. Five 2.3 ± 0.5 mm thick slices were acquired at 15 mm/s scan speed and 500-µm resolution. Logarithmic or linear regression models were fitted to EDTA or CuCl2 versus density and T2 relaxation data. RESULTS: Density (D) was linearly dependent on CuCl2 (D = 0.27 [CuCl2] + 63.92, R2 = 0.84, P = 0.01) and invariant to EDTA. T2 relaxation time was related negatively to CuCl2 (T2 = -10.13 ln [CuCl2] + 66.70, R2 = 0.91, P < .01) and positively to EDTA (T2 = 5.72 ln [EDTA] + 54.47, R2 = 0.86, P < .01). Reproducibility within and between phantoms of the same compositions was acceptable (<5% error). Long-term stability was achieved for density but poorer for T2 relaxation time. CONCLUSIONS: This phantom optimization method provides a means for altering a soft tissue phantom suited for calibrating magnetic resonance imaging and QCT signals within values representative of muscle. Phantoms can be used during scans for calibrating magnetic resonance signals between and within individuals over time and can cross-calibrate different scanners.