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Value of Dual-Energy CT-Derived Metrics for the Prediction of Bone Non-union in Distal Radius Fractures.

RATIONALE AND OBJECTIVES: Bone non-union is a serious complication of distal radius fractures (DRF) that can result in functional limitations and persistent pain. However, no accepted method has been established to identify patients at risk of developing bone non-union yet. This study aimed to compare various CT-derived metrics for bone mineral density (BMD) assessment to identify predictive values for the development of bone non-union. MATERIALS AND METHODS: CT images of 192 patients with DRFs who underwent unenhanced dual-energy CT (DECT) of the distal radius between 03/2016 and 12/2020 wer

The Relationship Between Body Composition and Bone Quality Measured with HR-pQCT in Peritoneal Dialysis Patients.

BACKGROUND: Bone is known to be impaired in chronic kidney disease and dialysis patients. Recent studies have shown that body composition (fat mass and lean mass) may impact bone health. Some of these effects may be related to mediators that are secreted by adipose tissue. METHODS: The aim of this study was to evaluate the association between body composition (dual x-ray absorptiometry [DEXA]) and adipokines (leptin, adiponectin), with bone density and microarchitecture assessed with high-resolution peripheral quantitative computed tomography (HR-pQCT) in chronic peritoneal dialysis (PD) pati

Assessment of the relationship between the mandibular cortex on panoramic radiographs and the risk of bone fracture and vascular disease in 80-year-olds.

OBJECTIVES: The objective of this study was to assess cortical measurements on panoramic radiographs in 80-year-old subjects to predict bone fracture and vascular disease risks. METHODS: The cortical width and shape (normal cortex, mildly to moderately eroded cortex, and severely eroded cortex) were evaluated on 659 panoramic radiographs obtained from 262 men and 397 women, all of whom were 80 years old. At baseline, a general medical examination, including heel bone density, was performed in all subjects. Fractures and vascular disease occurring within 5 years after the baseline examination

Bone Graft Options in Upper-Extremity Surgery.

Bone grafting in the upper extremity is an important consideration in patients with injuries or conditions resulting in missing bone stock. A variety of indications can necessitate bone grafting in the upper extremity, including fractures with acute bone loss, nonunions, malunions, bony lesions, and bone loss after osteomyelitis. Selecting the appropriate bone graft option for the specific consideration is important to ensure optimal patient outcomes. Considerations such as donor site morbidity and the amount and characteristics of bone graft needed all weigh in the decision making regarding w

Quantitative (31)P NMR spectroscopy and (1)H MRI measurements of bone mineral and matrix density differentiate metabolic bone diseases in rat models.

In this study, bone mineral density (BMD) of normal (CON), ovariectomized (OVX), and partially nephrectomized (NFR) rats was measured by (31)P NMR spectroscopy; bone matrix density was measured by (1)H water- and fat-suppressed projection imaging (WASPI); and the extent of bone mineralization (EBM) was obtained by the ratio of BMD/bone matrix density. The capability of these MR methods to distinguish the bone composition of the CON, OVX, and NFR groups was evaluated against chemical analysis (gravimetry). For cortical bone specimens, BMD of the CON and OVX groups was not significantly differen…

[The effect of retinoic acid on induction of osteoporotic model rats and the possible mechanism].

OBJECTIVE: To observe the effect of retinoic acid on induction of osteoporotic model in rats and analyze the mechanism therein involved. METHODS: SD rats were treated with retinoic acid 80 mg/(kg x d) by gastrogavage for 15 days to induce osteoporosis and were killed in batches at 0, 30 and 60 days after drug withdrawal. The levels of Ca, P, BGP, E2, IGF-1, AKP and TRAP in serum were assayed, the collagen and proteoglycan contents of bone and bone mineral density (BMD) were determined, and the morphological changes in cancellous and cortical bone and growth plate cartilage (GPC) of femurs fro…

The association between insulin use and volumetric bone mineral density, bone micro-architecture and bone strength of the distal radius in patients with type 2 diabetes - The Maastricht study.

Type 2 diabetes mellitus (T2DM) has been associated with an increased risk of fractures, despite normal to increased bone mineral density (BMD). Insulin use is one of the factors linked to this increased fracture risk. However, direct negative effects of insulin on bone quality are not expected since insulin is thought to be anabolic to bone. In this cross-sectional study the association between insulin use and volumetric BMD (vBMD), bone micro-architecture and bone strength of the distal radius, as measured with HR-pQCT, was examined. Data from 50 participants with T2DM of The Maastricht Stud

Effects of testosterone and growth hormone on the structural and mechanical properties of bone by micro-MRI in the distal tibia of men with hypopituitarism.

CONTEXT: Severe deficiencies of testosterone (T) and GH are associated with low bone mineral density (BMD) and increased fracture risk. Repl … e structural and mechanical properties of trabecular bone but decreased most of these properties of cortical bone, illustrating the potential importance of assessing trabecular and cortical bone separately in future studies of the effect of testosterone on bone.

The Author's Technique for the Management of Unstable Scaphoid Nonunions: Tips and Tricks.

This article presents historical aspects, rationale, indications, planning, and execution of anterior interpositional bone grafting technique for unstable scaphoid nonunions. The author's original technique considers four points: (1) preoperative planning based on comparative anteroposterior radiographs in maximal ulnar deviation was used to calculate resection zone, size of the graft, and scaphoid length; (2) a volar approach was used; (3) an iliac crest wedge-shaped corticocancellous graft was interposed; and (4) Kirschner wires were inserted for fixation. Contemporary refinements of the tec

Effects of vitamin K2 on the development of osteopenia in rats as the models of osteoporosis.

Vitamin K2 is widely used for the treatment of osteoporosis in Japan. To understand the effects of vitamin K2 on bone mass and bone metaboli … moral neck. The use of vitamin K2 alone suppressed the increase in trabecular bone turnover and endocortical bone resorption, which attenuated the development of cancellous and cortical osteopenia in orchidectomized rats. In addition, vitamin K2 inhibited the decrease in bone formation in prednisolone-treated rats, thereby preventing cancellous and cortical ost …

FGF-23 and sclerostin in serum and bone of CKD patients.

AIMS: Renal osteodystrophy occurs in the early stages of chronic kidney disease (CKD) and progresses during loss of kidney function. Fibrobl … - to 7.1-fold starting at CKD-2. No difference in FGF-23 expression was seen between trabecular and cortical bone. Sclerostin expression in bone correlated positively with CKD stages (p < 0.001) with an increase from 3.8- to 5.1-fold starting at CKD-2. This increase was progressive and significantly greater in cortical than cancellous bone. FGF-23 and sclerosti …

Bone status in primary hyperparathyroidism.

Traditional bone involvement, such as osteoitis fibrosa, has become very rare (< 1%) in primary hyperparathyroidism (PHPT); nevertheless, fr … urgical decision with a threshold: Z-score < -2. The demineralisation predominates on sites rich in cortical bone (1/3 proximal of the distal radius); the radius, which was the first site evaluated for technical reasons, is also the most discriminating one. Spine demineralisation is met in more severe forms and BMD measurement of the whole body is promising but …

Comparison of bone microstructures via high-resolution peripheral quantitative computed tomography in patients with different stages of chronic kidney disease before and after starting hemodialysis.

Chronic kidney disease (CKD) negatively affects bone strength; however, the osteoporotic conditions in patients with CKD are not fully under … hemodialysis (in patients with CKD stage 5 D), patients with CKD stage 4-5, and healthy volunteers. Cortical bone parameters were lower in the CKD group than in healthy controls. Tibial cortical and trabecular bone parameters (cortical thickness, cortical area, trabecular volumetric bone mineral density, trabecular-bone volume fraction, and trabecular thickness …

Microarray profiling of diaphyseal bone of rats suffering from hypervitaminosis A.

Vitamin A is the only known compound that produces spontaneous fractures in rats. In an effort to resolve the molecular mechanism behind this effect, we fed young male rats high doses of vitamin A and performed microarray analysis of diaphyseal bone with and without marrow after 1 week, i.e., just before the first fractures appeared. Of the differentially expressed genes in cortical bone, including marrow, 98% were upregulated. In contrast, hypervitaminotic cortical bone without marrow showed reduced expression of 37% of differentially expressed genes. Gene ontology (GO) analysis revealed that…

Strain-specific alterations in the skeletal response to adenine-induced chronic kidney disease are associated with differences in parathyroid hormone levels.

UNLABELLED: Chronic kidney disease (CKD) leads to loss of cortical bone through cortical thinning and the development of cortical porosity. The goal of this current study was to assess cortical bone alterations to adenine-induced chronic kidney disease (CKD) in two strains of mice with known genetic differences in cortical thickness. We hypothesized that C3H mice with thicker cortices and baseline levels of intracortical remodeling would have greater cortical porosity in response to adenine-induced CKD compared to B6 animals. METHODS: Female C57BL/6 J (B6) and C3H/Hej (C3H) at 16-weeks of age…

Severe Osteoporosis in Larsen Syndrome-A Case Report of Bone Morphology and A Novel Filamin B (FLNB) Variant.

Larsen syndrome is a rare genetic condition characterized by facial dysmorphism and skeletal deformities. It is caused by heterozygous patho … sociated with low bone mineral density reflecting severe osteoporosis and an altered trabecular and cortical bone structure, while bone turnover was less affected at the time of analysis.

Effect of bone quality and quantity on the primary stability of dental implants in a simulated bicortical placement.

OBJECTIVES: Conventional dental implants inserted in the molar region of the maxilla will reach into the sinus maxillaris when alveolar ridge height is limited. When surgery is performed without prior augmentation of the sinus floor, primary stability of the implant is important for successful osseointegration. This study aimed at identifying the impact of bone quality and quantity at the implantation site on primary implant stability of a simulated bicortical placement. MATERIALS AND METHODS: In our in vitro measurements, bone mineral density, total bone thickness and overall cortical bone t…

Characteristics and dimensions of the Schneiderian membrane and apical bone in maxillary molars referred for apical surgery: a comparative radiographic analysis using limited cone beam computed tomography.

INTRODUCTION: The purpose of the present study was to evaluate the thickness and the anatomic characteristics of the Schneiderian membrane and cortical bone using limited cone beam computed tomography (CBCT) scannning in patients referred for planning of apical surgery of maxillary molars. METHODS: This controlled study included 2 cohorts of patients (n = 50 for each group). For patients in group 1 (with apical pathology), 3 measurements in millimeters were performed using coronal and sagittal CBCT slices: the dimension of the apical lesion in the axis of the root, the width of the cortical b…

Бифазная потеря костей в экспериментальном аутоиммунном энцефаломиэлите.

Множественный склероз (MS) — хроническое аутоиммунное расстройство центральной нервной системы (CNS) и общая причина неврологических расстройств у молодых людей. Хотя известно, что периферийный иммунный ландшафт изменяется у людей с MS (pwMS), влияние на другие системы органов, помимо CNS, часто игнорируется. Помимо неврологических дефицитов, ПВМС страдает от расстройства костного здоровья и повышенного риска разрушения. Однако механизмы, лежащие в основе потери костей в ПТМС, плохо понимаются. Здесь мы изучили костную микроархитектуру, а также клеточные и молекулярные механизмы изменения кост

Совпадение в аннотации оригинала
Multiple sclerosis (MS) is a chronic autoimmune disorder of the central nervous system (CNS) and a common cause of neurological disabilities … S and EAE mice have reduced bone mineral density characterized by a combined loss of trabecular and cortical bone. Intriguingly, bone loss in EAE followed a biphasic dynamic defined by increased osteocyte apoptosis associated with decreased bone formation in acute EAE and increased bone resorption in the chronic phase, which could be explained by increased CXCL …

Biomechanical analysis of iliac crest loading following cortico-cancellous bone harvesting.

BACKGROUND: Iliac crest bone harvesting is a frequently performed surgical procedure widely used to treat bone defects. The objective of this study is to assess the biomechanical quantities related to risk for pelvic fracture after harvesting an autologous bone graft at the anterior iliac crest. METHODS: Finite element models with a simulated harvest site (sized 15 × 20 mm, 15 × 35 mm, 30 × 20 mm and 30 × 35 mm) in the iliac wing are created. The relevant loading case is when the ipsilateral leg is lifted off the ground. Musculoskeletal analysis is utilized to compute the muscle and joint for