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1.
Clinics (Sao Paulo) ; 79: 100430, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38991370

RESUMO

INTRODUCTION: Type 2 Diabetes (T2D) is associated with fractures, despite preserved Bone Mineral Density (BMD). This study aimed to evaluate the relationship between BMD and trabecular bone score (TBS) with the reallocation of fat within muscle in individuals with eutrophy, obesity, and T2D. METHODS: The subjects were divided into three groups: eutrophic controls paired by age and sex with the T2D group (n = 23), controls diagnosed with obesity paired by age, sex, and body mass index with the T2D group (n = 27), and the T2D group (n = 29). BMD and body fat percentage were determined using dual-energy X-Ray absorptiometry. TBS was determined using TBS iNsight software. Intra and extramyocellular lipids in the soleus were measured using proton magnetic resonance spectroscopy. RESULTS: TBS was lower in the T2D group than in the other two groups. Glycated hemoglobin (A1c) was negatively associated with TBS. Body fat percentage was negatively associated with TBS and Total Hip (TH) BMD. TH BMD was positively associated with intramuscular lipids. A trend of negative association was observed between intramuscular lipids and TBS. CONCLUSION: This study showed for the first time that the reallocation of lipids within muscle has a negative association with TBS. Moreover, these results are consistent with previous studies showing a negative association between a parameter related to insulin resistance (intramuscular lipids) and TBS.


Assuntos
Absorciometria de Fóton , Tecido Adiposo , Densidade Óssea , Osso Esponjoso , Diabetes Mellitus Tipo 2 , Músculo Esquelético , Humanos , Diabetes Mellitus Tipo 2/fisiopatologia , Diabetes Mellitus Tipo 2/metabolismo , Masculino , Feminino , Pessoa de Meia-Idade , Densidade Óssea/fisiologia , Osso Esponjoso/diagnóstico por imagem , Estudos de Casos e Controles , Tecido Adiposo/diagnóstico por imagem , Adulto , Obesidade/fisiopatologia , Obesidade/metabolismo , Hemoglobinas Glicadas/análise , Índice de Massa Corporal , Idoso , Controle Glicêmico , Valores de Referência
2.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 41(3): 584-594, 2024 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-38932546

RESUMO

Triply periodic minimal surface (TPMS) is widely used because it can be used to control the shape of porous scaffolds precisely by formula. In this paper, an I-wrapped package (I-WP) type porous scaffolds were constructed. The finite element method was used to study the relationship between the wall thickness and period, the morphology and mechanical properties of the scaffolds, as well as to study the compression and fluid properties. It was found that the porosity of I-WP type scaffolds with different wall thicknesses (0.1 ~ 0.2 mm) and periods (I-WP 1 ~ I-WP 5) ranged from 68.01% ~ 96.48%, and the equivalent elastic modulus ranged from 0.655 ~ 18.602 GPa; the stress distribution of the scaffolds tended to be uniform with the increase of periods and wall thicknesses; the equivalent elastic modulus of the I-WP type scaffolds was basically unchanged after the topology optimization, and the permeability was improved by 52.3%. In conclusion, for the I-WP type scaffolds, the period parameter can be adjusted first, then the wall thickness parameter can be controlled. Topology optimization can be combined to meet the design requirements. The I-WP scaffolds constructed in this paper have good mechanical properties and meet the requirements of repairing human bone tissue, which may provide a new choice for the design of artificial bone trabecular scaffolds.


Assuntos
Análise de Elementos Finitos , Alicerces Teciduais , Alicerces Teciduais/química , Porosidade , Módulo de Elasticidade , Engenharia Tecidual/métodos , Humanos , Osso e Ossos/fisiologia , Teste de Materiais , Osso Esponjoso , Propriedades de Superfície , Estresse Mecânico , Substitutos Ósseos/química
4.
PLoS One ; 19(6): e0290914, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38889162

RESUMO

Significant alterations to subchondral trabecular bone microarchitecture are observed in late-stage osteoarthritis (OA). However, detailed investigation of these changes to bone in the ankle are under-reported. This study aimed to fully characterise the trabecular morphology in OA ankle bone specimens compared to non-diseased (ND) controls using both standard and individual-trabecular segmentation-based (ITS) analyses. Ten ND tibial bone specimens were extracted from three cadaveric ankles, as well as five OA bone specimens from patients undergoing total ankle arthroplasty surgery. Each specimen was scanned using microcomputed tomography from which a 4 mm cuboidal volume was extracted for analysis. Morphological parameters for the subchondral trabecular bone were measured using BoneJ (NIH ImageJ) and 3D ITS for whole volumes and at each depth level in 1 mm increments. The results show an overall increase in bone volume fraction (p<0.01) and trabecular thickness (p<0.001) with OA, with a decrease in anisotropy (p<0.05). ITS analysis showed OA bone was composed of more rod-like trabeculae and plate-like trabeculae compared to ND bone. Numerous properties were depth dependent, but the results demonstrated that towards the subchondral bone plate, both rod- and plate-like trabeculae were thicker, rods were longer and plates had increased surface area. Overall, this study has verified key microstructural alterations to ankle subchondral bone that are found in other OA lower-limb joints. Depth-based analysis has highlighted differences of interest for further evaluation into the remodelling mechanisms that occur with OA, which is critical to understanding the role of subchondral bone microarchitecture in the progression of the disease.


Assuntos
Articulação do Tornozelo , Osteoartrite , Tíbia , Microtomografia por Raio-X , Humanos , Osteoartrite/patologia , Osteoartrite/diagnóstico por imagem , Feminino , Idoso , Masculino , Articulação do Tornozelo/diagnóstico por imagem , Articulação do Tornozelo/patologia , Pessoa de Meia-Idade , Tíbia/patologia , Tíbia/diagnóstico por imagem , Osso Esponjoso/patologia , Osso Esponjoso/diagnóstico por imagem , Idoso de 80 Anos ou mais
5.
Forensic Sci Int Genet ; 71: 103067, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38833778

RESUMO

Significant variation exists in the molecular structure of compact and trabecular bone. In compact bone full dissolution of the bone powder is required to efficiently release the DNA from hydroxyapatite. In trabecular bone where soft tissues are preserved, we assume that full dissolution of the bone powder is not required to release the DNA from collagen. To investigate this issue, research was performed on 45 Second World War diaphysis (compact bone)-epiphysis (trabecular bone) femur pairs, each processed with a full dissolution (FD) and partial dissolution (PD) extraction method. DNA quality and quantity were assessed using qPCR PowerQuant analyses, and autosomal STRs were typed to confirm the authenticity of isolated DNA. Our results support different mechanisms of DNA preservation in compact and trabecular bone because FD method was more efficient than PD method only in compact bone, and no difference in DNA yield was observed in trabecular bone, showing no need for full dissolution of the bone powder when trabecular bone tissue is processed. In addition, a significant difference in DNA yield was observed between compact and trabecular bone when PD was applied, with more DNA extracted from trabecular bone than compact bone. High suitability of trabecular bone processed with PD method is also supported by the similar quantities of DNA isolated by FD method when applied to both compact and trabecular bone. Additionally similar quantities of DNA were isolated when compact bone was extracted with FD method and trabecular bone was extracted with PD method. Processing trabecular bone with PD method in routine identification of skeletonized human remains shortens the extraction procedure and simplifies the grinding process.


Assuntos
Osso Esponjoso , DNA , Fêmur , Repetições de Microssatélites , Humanos , DNA/genética , Fêmur/química , Impressões Digitais de DNA , Reação em Cadeia da Polimerase , Masculino , Reação em Cadeia da Polimerase em Tempo Real
6.
Sci Rep ; 14(1): 12967, 2024 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-38839844

RESUMO

Osteoporosis is a common skeletal disease affecting millions of individuals world-wide, with an increased risk of fracture, and a decreased quality of life. Despite its well-known consequences, the etiology of osteoporosis and optimal treatment methods are not fully understood. Human genetic studies have identified genetic variants within the FMN2/GREM2 locus to be associated with trabecular volumetric bone mineral density (vBMD) and vertebral and forearm fractures, but not with cortical bone parameters. GREM2 is a bone morphogenetic protein (BMP) antagonist. In this study, we employed Grem2-deficient mice to investigate whether GREM2 serves as the plausible causal gene for the fracture signal at the FMN2/GREM2 locus. We observed that Grem2 is moderately expressed in bone tissue and particularly in osteoblasts. Complete Grem2 gene deletion impacted mouse survival and body growth. Partial Grem2 inactivation in Grem2+/- female mice led to increased trabecular BMD of femur and increased trabecular bone mass in tibia due to increased trabecular thickness, with an unchanged cortical thickness, as compared with wildtype littermates. Furthermore, Grem2 inactivation stimulated osteoblast differentiation, as evidenced by higher alkaline phosphatase (Alp), osteocalcin (Bglap), and osterix (Sp7) mRNA expression after BMP-2 stimulation in calvarial osteoblasts and osteoblasts from the long bones of Grem2-/- mice compared to wildtype littermates. These findings suggest that GREM2 is a possible target for novel osteoporotic treatments, to increase trabecular bone mass and prevent osteoporotic fractures.


Assuntos
Densidade Óssea , Osso Esponjoso , Osteoblastos , Animais , Feminino , Camundongos , Proteína Morfogenética Óssea 2/metabolismo , Proteína Morfogenética Óssea 2/genética , Osso Esponjoso/metabolismo , Osso Esponjoso/patologia , Diferenciação Celular , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Camundongos Knockout , Osteoblastos/metabolismo , Osteogênese/genética , Osteoporose/genética , Osteoporose/patologia , Osteoporose/metabolismo
7.
Sci Rep ; 14(1): 13065, 2024 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-38844829

RESUMO

The TBS is a new method for clinicians to assess the bone quality. It is directly related to the mechanical strength of bone and helps predict fracture risk. The present analysis aimed to investigate the associations between serum PTH levels and TBS by analyzing data from the National Health and Nutrition Examination Survey (NHANES). A total of 3516 participants from the NHANES 2005-2006 were included in this cross-sectional study. The independent variable was serum PTH, and the outcome variable was TBS. The associations of serum PTH levels with TBS were examined using multivariable linear regression models. After adjusting for covariates, there was a negative association between serum PTH level and TBS (ß = - 0.0034; 95% confidence interval, - 0.0050 to - 0.0017). However, in the subgroup analysis stratified by gender, race, and age, this association became negative only in Non-Hispanic White (ß = - 0.0047, 95% CI: -  0.0071 to -  0.0048) and young people (age < 60) (ß = - 0.0036, 95% CI: - 0.0057, - 0.0016), regardless of gender. In addition, the association of serum PTH with TBS was an U-shaped curve, with a point of inflection at 6.71 pmol/L. This study showed that serum PTH level was negatively associated with TBS. Maintaining PTH levels in a lower reasonable clinical range may be beneficial to bone health, especially for young non-Hispanic white.


Assuntos
Osso Esponjoso , Inquéritos Nutricionais , Hormônio Paratireóideo , Humanos , Hormônio Paratireóideo/sangue , Masculino , Feminino , Estudos Transversais , Pessoa de Meia-Idade , Adulto , Densidade Óssea , Idoso
8.
Front Endocrinol (Lausanne) ; 15: 1394263, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38904042

RESUMO

Introduction: Caloric restriction (CR) is a nutritional intervention that increases life expectancy while lowering the risk for cardio-metabolic disease. Its effects on bone health, however, remain controversial. For instance, CR has been linked to increased accumulation of bone marrow adipose tissue (BMAT) in long bones, a process thought to elicit detrimental effects on bone. Qualitative differences have been reported in BMAT in relation to its specific anatomical localization, subdividing it into physiological and potentially pathological BMAT. We here examine the local impact of CR on bone composition, microstructure and its endocrine profile in the context of aging. Methods: Young and aged male C57Bl6J mice were subjected to CR for 8 weeks and were compared to age-matched littermates with free food access. We assessed bone microstructure and BMAT by micro-CT, bone fatty acid and transcriptomic profiles, and bone healing. Results: CR increased tibial BMAT accumulation and adipogenic gene expression. CR also resulted in elevated fatty acid desaturation in the proximal and mid-shaft regions of the tibia, thus more closely resembling the biochemical lipid profile of the distally located, physiological BMAT. In aged mice, CR attenuated trabecular bone loss, suggesting that CR may revert some aspects of age-related bone dysfunction. Cortical bone, however, was decreased in young mice on CR and remained reduced in aged mice, irrespective of dietary intervention. No negative effects of CR on bone regeneration were evident in either young or aged mice. Discussion: Our findings indicate that the timing of CR is critical and may exert detrimental effects on bone biology if administered during a phase of active skeletal growth. Conversely, CR exerts positive effects on trabecular bone structure in the context of aging, which occurs despite substantial accumulation of BMAT. These data suggest that the endocrine profile of BMAT, rather than its fatty acid composition, contributes to healthy bone maintenance in aged mice.


Assuntos
Adipócitos , Envelhecimento , Restrição Calórica , Osso Esponjoso , Camundongos Endogâmicos C57BL , Animais , Masculino , Restrição Calórica/métodos , Camundongos , Envelhecimento/fisiologia , Osso Esponjoso/patologia , Adipócitos/metabolismo , Medula Óssea/metabolismo , Tíbia/metabolismo
9.
Sci Rep ; 14(1): 9977, 2024 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-38693297

RESUMO

This paper investigates trabecular bone ontogenetic changes in two different Polish populations, one prehistoric and the other historical. The studied populations are from the Brzesc Kujawski region in Kujawy (north-central Poland), one from the Neolithic Period (4500-4000 BC) and one from the Middle Ages (twelfth-sixteenth centuries AD), in total 62 vertebral specimens (32 males, 30 females). Eight morphometric parameters acquired from microCT scan images were analysed. Two-way ANOVA after Box-Cox transformation and multifactorial regression model were calculated. A significant decrease in percentage bone volume fraction (BV/TV; [%]) with age at death was observed in the studied sample; Tb.N (trabecular number) was also significantly decreased with age; trabecular separation (Tb.Sp) increased with advancing age; connectivity density (Conn.D) was negatively correlated with biological age and higher in the Neolithic population. These data are found to be compatible with data from the current biomedical literature, while no loss of horizontal trabeculae was recorded as would be expected based on modern osteoporosis.


Assuntos
Osso Esponjoso , Humanos , Polônia , Masculino , Feminino , Adulto , Osso Esponjoso/anatomia & histologia , Osso Esponjoso/diagnóstico por imagem , História Medieval , Pessoa de Meia-Idade , Coluna Vertebral/anatomia & histologia , Coluna Vertebral/diagnóstico por imagem , História Antiga , Microtomografia por Raio-X , Fatores Etários , Idoso , Densidade Óssea , Fatores Sexuais , Adulto Jovem
10.
BMC Med Imaging ; 24(1): 101, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38693510

RESUMO

Bone strength depends on both mineral content and bone structure. Measurements of bone microstructure on specimens can be performed by micro-CT. In vivo measurements are reliably performed by high-resolution peripheral computed tomography (HR-pQCT) using dedicated software. In previous studies from our research group, trabecular bone properties on CT data of defatted specimens from many different CT devices have been analyzed using an Automated Region Growing (ARG) algorithm-based code, showing strong correlations to micro-CT.The aim of the study was to validate the possibility of segmenting and measuring trabecular bone structure from clinical CT data of fresh-frozen human wrist specimens. Data from micro-CT was used as reference. The hypothesis was that the ARG-based in-house built software could be used for such measurements.HR-pQCT image data at two resolutions (61 and 82 µm isotropic voxels) from 23 fresh-frozen human forearms were analyzed. Correlations to micro-CT were strong, varying from 0.72 to 0.99 for all parameters except trabecular termini and nodes. The bone volume fraction had correlations varying from 0.95 to 0.98 but was overestimated compared to micro-CT, especially at the lower resolution. Trabecular separation and spacing were the most stable parameters with correlations at 0.80-0.97 and mean values in the same range as micro-CT.Results from this in vitro study show that an ARG-based software could be used for segmenting and measuring 3D trabecular bone structure from clinical CT data of fresh-frozen human wrist specimens using micro-CT data as reference. Over-and underestimation of several of the bone structure parameters must however be taken into account.


Assuntos
Algoritmos , Osso Esponjoso , Microtomografia por Raio-X , Humanos , Osso Esponjoso/diagnóstico por imagem , Idoso , Masculino , Feminino , Pessoa de Meia-Idade , Punho/diagnóstico por imagem , Software , Idoso de 80 Anos ou mais
11.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 38(5): 535-541, 2024 May 15.
Artigo em Chinês | MEDLINE | ID: mdl-38752238

RESUMO

Objective: To evaluate the effectiveness of using titanium alloy trabecular bone three-dimensional (3D) printed artificial vertebral body in treating cervical ossification of the posterior longitudinal ligament (OPLL). Methods: A retrospective analysis was conducted on clinical data from 45 patients with cervical OPLL admitted between September 2019 and August 2021 and meeting the selection criteria. All patients underwent anterior cervical corpectomy and decompression, interbody bone graft fusion, and titanium plate internal fixation. During operation, 21 patients in the study group received titanium alloy trabecular bone 3D printed artificial vertebral bodies, while 24 patients in the control group received titanium cages. There was no significant difference in baseline data such as gender, age, disease duration, affected segments, or preoperative pain visual analogue scale (VAS) score, Japanese Orthopaedic Association (JOA) score, Neck Disability Index (NDI), vertebral height, and C 2-7Cobb angle ( P>0.05). Operation time, intraoperative blood loss, and occurrence of complications were recorded for both groups. Preoperatively and at 3 and 12 months postoperatively, the functionality and symptom relief were assessed using JOA scores, VAS scores, and NDI evaluations. The vertebral height and C 2-7 Cobb angle were detected by imaging examinations and the implant subsidence and intervertebral fusion were observed. Results: The operation time and incidence of complications were significantly lower in the study group than in the control group ( P<0.05), while the difference in intraoperative blood loss between the two groups was not significant ( P>0.05). All patients were followed up 12-18 months, with the follow-up time of (14.28±4.34) months in the study group and (15.23±3.54) months in the control group, showing no significant difference ( t=0.809, P=0.423). The JOA score, VAS score, and NDI of the two groups improved after operation, and further improved at 12 months compared to 3 months, with significant differences ( P<0.05). At each time point, the study group exhibited significantly higher JOA scores and improvement rate compared to the control group ( P<0.05); but there was no significantly difference in VAS score and NDI between the two groups ( P>0.05). Imaging re-examination showed that the vertebral height and C 2-7Cobb angle of the two groups significantly increased at 3 and 12 months after operation ( P<0.05), and there was no significant difference between 3 and 12 months after operation ( P>0.05). At each time point, the vertebral height and C 2-7Cobb angle of the study group were significantly higher than those of the control group ( P<0.05), and the implant subsidence rate was significantly lower than that of the control group ( P<0.05). However, there was no significant difference in intervertebral fusion rate between the two groups ( P>0.05). Conclusion: Compared to traditional titanium cages, the use of titanium alloy trabecular bone 3D-printed artificial vertebral bodies for treating cervical OPLL results in shorter operative time, fewer postoperative complications, and lower implant subsidence rates, making it superior in vertebral reconstruction.


Assuntos
Ligas , Vértebras Cervicais , Ossificação do Ligamento Longitudinal Posterior , Impressão Tridimensional , Fusão Vertebral , Titânio , Humanos , Ossificação do Ligamento Longitudinal Posterior/cirurgia , Vértebras Cervicais/cirurgia , Estudos Retrospectivos , Fusão Vertebral/métodos , Fusão Vertebral/instrumentação , Descompressão Cirúrgica/métodos , Osso Esponjoso , Resultado do Tratamento , Corpo Vertebral/cirurgia , Feminino , Masculino , Placas Ósseas , Pessoa de Meia-Idade
12.
Front Endocrinol (Lausanne) ; 15: 1287591, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38774224

RESUMO

Purpose: To determine whether there are alterations in marrow fat content in individuals first-time diagnosed with type 1 diabetes mellitus (T1DM) and to explore the associations between marrow fat fraction and MRI-based findings in trabecular bone microarchitecture. Method: A case-control study was conducted, involving adults with first-time diagnosed T1DM (n=35) and age- and sex-matched healthy adults (n=46). Dual-energy X-ray absorptiometry and 3 Tesla-MRI of the proximal tibia were performed to assess trabecular microarchitecture and vertebral marrow fat fraction. Multiple linear regression analysis was used to test the associations of marrow fat fraction with trabecular microarchitecture and bone density while adjusting for potential confounding factors. Results: In individuals first-time diagnosed with T1DM, the marrow fat fraction was significantly higher (p < 0.001) compared to healthy controls. T1DM patients also exhibited higher trabecular separation [median (IQR): 2.19 (1.70, 2.68) vs 1.81 (1.62, 2.10), p < 0.001], lower trabecular volume [0.45 (0.30, 0.56) vs 0.53 (0.38, 0.60), p = 0.013], and lower trabecular number [0.37 (0.26, 0.44) vs 0.41 (0.32, 0.47), p = 0.020] compared to controls. However, bone density was similar between the two groups (p = 0.815). In individuals with T1DM, there was an inverse association between marrow fat fraction and trabecular volume (r = -0.69, p < 0.001) as well as trabecular number (r = -0.55, p < 0.001), and a positive association with trabecular separation (r = 0.75, p < 0.001). Marrow fat fraction was independently associated with total trabecular volume (standardized ß = -0.21), trabecular number (ß = -0.12), and trabecular separation (ß = 0.57) of the proximal tibia after adjusting for various factors including age, gender, body mass index, physical activity, smoking status, alcohol consumption, blood glucose, plasma glycated hemoglobin, lipid profile, and bone turnover biomarkers. Conclusions: Individuals first-time diagnosed with T1DM experience expansion of marrow adiposity, and elevated marrow fat content is associated with MRI-based trabecular microstructure.


Assuntos
Densidade Óssea , Medula Óssea , Osso Esponjoso , Diabetes Mellitus Tipo 1 , Imageamento por Ressonância Magnética , Humanos , Masculino , Feminino , Diabetes Mellitus Tipo 1/diagnóstico por imagem , Diabetes Mellitus Tipo 1/patologia , Imageamento por Ressonância Magnética/métodos , Osso Esponjoso/diagnóstico por imagem , Osso Esponjoso/patologia , Adulto , Estudos de Casos e Controles , Medula Óssea/diagnóstico por imagem , Medula Óssea/patologia , Absorciometria de Fóton , Tecido Adiposo/diagnóstico por imagem , Tecido Adiposo/patologia , Pessoa de Meia-Idade , Adulto Jovem
13.
Injury ; 55(6): 111583, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38692209

RESUMO

INTRODUCTION: Bone grafts for scaphoid nonunion with deformity include cortcicocancellous or pure cancellous bone grafts. This study compared the outcomes between two types of bone grafts when employing a volar locking-plate in patients with scaphoid nonunion with dorsal intercalated segmental instability (DISI). PATIENTS AND METHODS: This retrospective study included 34 patients with scaphoid nonunion and DISI due to humpback deformity treated between March 2017 and January 2022. Two types of bone grafts were obtained from iliac crest. Twenty of the corticocancellous (CC) group underwent a wedge-shaped graft, while 14 patients of the pure cancellous (C-only) group received graft chips. In both groups, a 1.5-mm anatomically pre-contoured locking plate was used for fixation. Radiographic evaluations included the union rate and carpal alignment including scapholunate angle (SLA), radiolunate angle (RLA), intrascaphoid angle (ISA) and scaphoid height to length ratio (HLR). Clinical assessments encompassed wrist range-of-motion, grip strength, and patient-reported outcomes. RESULTS: Nineteen of the 20 patients in the CC group and 12 of the 14 patients in the C-only group respectively, achieving osseous union. The mean follow-up period in CC group was 14.7 (range, 12 ∼ 24) months and that in C-only group was 12.6 (range, 12 ∼ 15) months. Postoperatively, there were no significant intergroup differences of radiographic parameters including SLA (CC; 49.9° ± 6.7° vs. C-only; 48.9° ± 3.5°, P = 0.676), RLA (1.7° ± 6.4° vs. 2.4° ± 3.3°, P = 0.74), ISA (36° ± 7.5° vs. 36.6° ± 12.2°, P = 0.881), and HLR (0.54 ± 0.09 vs. 0.53 ± 0.05, P = 0.587). Clinical outcomes, including the flexion-extension arc (137° ± 30° vs. 158° ± 33°, P = 0.122), grip strength (93.4 % ± 15.4% vs. 99.5 % ± 16.7 %, P = 0.39), Quick Disabilities of the Arm, Shoulder, and Hand scores (11.2 ± 8.3 vs. 12.5 ± 7.7, P = 0.74) and Mayo Wrist Scores (81.2 ± 13.1 vs. 89 ± 11.4, P = 0.242) also showed no significant intergroup differences. CONCLUSIONS: Volar locking-plate fixation with pure cancellous bone grafts achieved outcomes comparable to those achieved with corticocancellous bone grafts in scaphoid nonunion with deformity, possibly due to the biomechanical advantages of the volar plate to provide structural supports.


Assuntos
Placas Ósseas , Transplante Ósseo , Osso Esponjoso , Fixação Interna de Fraturas , Fraturas não Consolidadas , Instabilidade Articular , Amplitude de Movimento Articular , Osso Escafoide , Humanos , Osso Escafoide/cirurgia , Osso Escafoide/lesões , Osso Escafoide/diagnóstico por imagem , Masculino , Feminino , Fraturas não Consolidadas/cirurgia , Fraturas não Consolidadas/fisiopatologia , Estudos Retrospectivos , Adulto , Transplante Ósseo/métodos , Osso Esponjoso/transplante , Fixação Interna de Fraturas/métodos , Instabilidade Articular/cirurgia , Instabilidade Articular/fisiopatologia , Resultado do Tratamento , Adulto Jovem , Articulação do Punho/cirurgia , Articulação do Punho/fisiopatologia , Articulação do Punho/diagnóstico por imagem , Força da Mão , Ílio/transplante , Radiografia , Consolidação da Fratura/fisiologia , Adolescente , Pessoa de Meia-Idade
14.
Int J Mol Sci ; 25(10)2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38791362

RESUMO

In the field of biomaterials for prosthetic reconstructive surgery, there is the lack of advanced innovative methods to investigate the potentialities of smart biomaterials before in vivo tests. Despite the complex osteointegration process being difficult to recreate in vitro, this study proposes an advanced in vitro tissue culture model of osteointegration using human bone. Cubic samples of trabecular bone were harvested, as waste material, from hip arthroplasty; inner cylindrical defects were created and assigned to the following groups: (1) empty defects (CTRneg); (2) defects implanted with a cytotoxic copper pin (CTRpos); (3) defects implanted with standard titanium pins (Ti). Tissues were dynamically cultured in mini rotating bioreactors and assessed weekly for viability and sterility. After 8 weeks, immunoenzymatic, microtomographic, histological, and histomorphometric analyses were performed. The model was able to simulate the effects of implantation of the materials, showing a drop in viability in CTR+, while Ti appears to have a trophic effect on bone. MicroCT and a histological analysis supported the results, with signs of matrix and bone deposition at the Ti implant site. Data suggest the reliability of the tested model in recreating the osteointegration process in vitro with the aim of reducing and refining in vivo preclinical models.


Assuntos
Osseointegração , Técnicas de Cultura de Tecidos , Titânio , Humanos , Técnicas de Cultura de Tecidos/métodos , Microtomografia por Raio-X , Osso e Ossos/citologia , Materiais Biocompatíveis , Próteses e Implantes , Osso Esponjoso/citologia
15.
Comput Biol Med ; 177: 108630, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38781643

RESUMO

Scaffolds are an essential component of bone tissue engineering to provide support and create a physiological environment for cells. Biomimetic scaffolds are a promising approach to fulfill the requirements. Bone allografts are widely used scaffolds due to their mechanical and structural characteristics. The scaffold geometry is well known to be an important determinant of induced mechanical stimulation felt by the cells. However, the impact of allograft geometry on permeability and wall shear stress distribution is not well understood. This information is essential for designing biomimetic scaffolds that provide a suitable environment for cells to proliferate and differentiate. The present study investigates the effect of geometry on the permeability and wall shear stress of bone allografts at both macroscopic and microscopic scales. Our results concluded that the wall shear stress was strongly correlated with the porosity of the allograft. The level of wall shear stress at a local scale was also determined by the surface curvature characteristics. The results of this study can serve as a guideline for future biomimetic scaffold designs that provide a mechanical environment favorable for osteogenesis and bone repair.


Assuntos
Estresse Mecânico , Alicerces Teciduais , Alicerces Teciduais/química , Porosidade , Humanos , Osso Esponjoso , Materiais Biomiméticos/química , Permeabilidade , Animais , Engenharia Tecidual/métodos , Resistência ao Cisalhamento
17.
Biomater Adv ; 161: 213871, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38692181

RESUMO

Drawing on the structure and components of natural bone, this study developed Mg-doped hydroxyapatite (Mg-HA) bioceramics, characterized by multileveled and oriented micro/nano channels. These channels play a critical role in ensuring both mechanical and biological properties, making bioceramics suitable for various bone defects, particularly those bearing loads. Bioceramics feature uniformly distributed nanogrooves along the microchannels. The compressive strength or fracture toughness of the Mg-HA bioceramics with micro/nano channels formed by single carbon nanotube/carbon fiber (CNT/CF) (Mg-HA(05-CNT/CF)) are comparable to those of cortical bone, attributed to a combination of strengthened compact walls and microchannels, along with a toughening mechanism involving crack pinning and deflection at nanogroove intersections. The introduction of uniform nanogrooves also enhanced the porosity by 35.4 %, while maintaining high permeability owing to the capillary action in the oriented channels. This leads to superior degradation properties, protein adsorption, and in vivo osteogenesis compared with bioceramics with only microchannels. Mg-HA(05-CNT/CF) exhibited not only high strength and toughness comparable to cortical bone, but also permeability similar to cancellous bone, enhanced cell activity, and excellent osteogenic properties. This study presents a novel approach to address the global challenge of applying HA-based bioceramics to load-bearing bone defects, potentially revolutionizing their application in tissue engineering.


Assuntos
Cerâmica , Durapatita , Magnésio , Durapatita/química , Magnésio/química , Cerâmica/química , Animais , Osso Cortical/efeitos dos fármacos , Osso Esponjoso , Osteogênese/efeitos dos fármacos , Teste de Materiais , Nanotubos de Carbono/química , Porosidade , Força Compressiva , Substitutos Ósseos/química , Materiais Biocompatíveis/química
18.
Bone ; 185: 117115, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38740120

RESUMO

Osteoporotic fractures, prevalent in the elderly, pose a significant health and economic burden. Current methods for predicting fracture risk, primarily relying on bone mineral density, provide only modest accuracy. If better spatial resolution of trabecular bone in a clinical scan were available, a more complete assessment of fracture risk would be obtained using microarchitectural measures of bone (i.e. trabecular thickness, trabecular spacing, bone volume fraction, etc.). However, increased resolution comes at the cost of increased radiation or can only be applied at small volumes of distal skeletal locations. This study explores super-resolution (SR) technology to enhance clinical CT scans of proximal femurs and better reveal the trabecular microarchitecture of bone. Using a deep-learning-based (i.e. subset of artificial intelligence) SR approach, low-resolution clinical CT images were upscaled to higher resolution and compared to corresponding MicroCT-derived images. SR-derived 2-dimensional microarchitectural measurements, such as degree of anisotropy, bone volume fraction, trabecular spacing, and trabecular thickness were within 16 % error compared to MicroCT data, whereas connectivity density exhibited larger error (as high as 1094 %). SR-derived 3-dimensional microarchitectural metrics exhibited errors <18 %. This work showcases the potential of SR technology to enhance clinical bone imaging and holds promise for improving fracture risk assessments and osteoporosis detection. Further research, including larger datasets and refined techniques, can advance SR's clinical utility, enabling comprehensive microstructural assessment across whole bones, thereby improving fracture risk predictions and patient-specific treatment strategies.


Assuntos
Tomografia Computadorizada por Raios X , Humanos , Tomografia Computadorizada por Raios X/métodos , Feminino , Idoso , Densidade Óssea/fisiologia , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/patologia , Masculino , Fêmur/diagnóstico por imagem , Fêmur/patologia , Aprendizado Profundo , Microtomografia por Raio-X/métodos , Processamento de Imagem Assistida por Computador/métodos , Idoso de 80 Anos ou mais , Osso Esponjoso/diagnóstico por imagem , Osso Esponjoso/patologia
19.
J Acoust Soc Am ; 155(4): 2670-2686, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38639562

RESUMO

Recently, ultrasound transit time spectroscopy (UTTS) was proposed as a promising method for bone quantitative ultrasound measurement. Studies have showed that UTTS could estimate the bone volume fraction and other trabecular bone structure in ultrasonic through-transmission measurements. The goal of this study was to explore the feasibility of UTTS to be adapted in ultrasonic backscatter measurement and further evaluate the performance of backscattered ultrasound transit time spectrum (BS-UTTS) in the measurement of cancellous bone density and structure. First, taking ultrasonic attenuation into account, the concept of BS-UTTS was verified on ultrasonic backscatter signals simulated from a set of scatterers with different positions and intensities. Then, in vitro backscatter measurements were performed on 26 bovine cancellous bone specimens. After a logarithmic compression of the BS-UTTS, a linear fitting of the log-compressed BS-UTTS versus ultrasonic propagated distance was performed and the slope and intercept of the fitted line for BS-UTTS were determined. The associations between BS-UTTS parameters and cancellous bone features were analyzed using simple linear regression. The results showed that the BS-UTTS could make an accurate deconvolution of the backscatter signal and predict the position and intensity of the simulated scatterers eliminating phase interference, even the simulated backscatter signal was with a relatively low signal-to-noise ratio. With varied positions and intensities of the scatterers, the slope of the fitted line for the log-compressed BS-UTTS versus ultrasonic propagated distance (i.e., slope of BS-UTTS for short) yield a high agreement (r2 = 99.84%-99.96%) with ultrasonic attenuation in simulated backscatter signal. Compared with the high-density cancellous bone, the low-density specimen showed more abundant backscatter impulse response in the BS-UTTS. The slope of BS-UTTS yield a significant correlation with bone mineral density (r = 0.87; p < 0.001), BV/TV (r = 0.87; p < 0.001), and cancellous bone microstructures (r up to 0.87; p < 0.05). The intercept of BS-UTTS was also significantly correlated with bone densities (r = -0.87; p < 0.001) and trabecular structures (|r|=0.43-0.80; p < 0.05). However, the slope of the BS-UTTS underestimated attenuation when measurements were performed experimentally. In addition, a significant non-linear relationship was observed between the measured attenuation and the attenuation estimated by the slope of the BS-UTTS. This study demonstrated that the UTTS method could be adapted to ultrasonic backscatter measurement of cancellous bone. The derived slope and intercept of BS-UTTS could be used in the measurement of bone density and microstructure. The backscattered ultrasound transit time spectroscopy might have potential in the diagnosis of osteoporosis in the clinic.


Assuntos
Osso e Ossos , Osso Esponjoso , Animais , Bovinos , Osso Esponjoso/diagnóstico por imagem , Espalhamento de Radiação , Ultrassonografia/métodos , Osso e Ossos/diagnóstico por imagem , Densidade Óssea/fisiologia , Análise Espectral/métodos
20.
Int J Oral Maxillofac Implants ; 39(2): 271-277, 2024 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-38657219

RESUMO

PURPOSE: To investigate the relationship between the structural parameters of trabecular bone obtained from CBCT imaging and the primary stability of dental implants. MATERIALS AND METHODS: Sixty patients underwent implant placement followed by primary stability evaluation via measurement of the insertion torque (IT) and the implant stability quotient (ISQ). Gray values (GV) and the fractal dimension (FD) were also measured using pretreatment CBCT images. RESULTS: FD values showed a positive and significant relationship with ISQ and IT values (P = .017 and P = .004, respectively). Additionally, there was a positive and significant correlation between GV and IT (P = .004) as well as between GV and ISQ (P = .010). FD and GV showed a considerable difference between the maxillary and mandibular jaws and were higher in the mandible. Only FD was significantly different between men and women and was higher in men. In the two age groups (older and younger than 45 years), only GV was considerably higher in people older than 45 (P < .05). CONCLUSIONS: Both fractal dimension and gray values obtained from CBCT are efficient methods for predicting the primary stability of the implant due to their relationship with ISQ and IT values.


Assuntos
Osso Esponjoso , Tomografia Computadorizada de Feixe Cônico , Implantes Dentários , Fractais , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Adulto , Osso Esponjoso/diagnóstico por imagem , Implantação Dentária Endóssea/métodos , Torque , Idoso , Retenção em Prótese Dentária , Mandíbula/diagnóstico por imagem
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