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2.
J Pak Med Assoc ; 74(8): 1555-1556, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39160737

RESUMO

Hepatocellular carcinoma (HCC), sixth most common cancer world-over, commonly metastasizes to lung, lymph nodes and adrenal glands. Incidence of osseous metastases in HCC has been reported to be 3-20 % which occurs predominantly in the axial skeleton. It only rarely occurs in the appendicular skeleton and that too as the solitary focus of metastatic deposit.3,4 We present a case of HCC with solitary osseous metastases to the proximal tibia.


Assuntos
Neoplasias Ósseas , Carcinoma Hepatocelular , Neoplasias Hepáticas , Tíbia , Humanos , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/secundário , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Neoplasias Ósseas/secundário , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/patologia , Masculino , Tíbia/diagnóstico por imagem , Tíbia/patologia , Tomografia Computadorizada com Tomografia Computadorizada de Emissão de Fóton Único , Pessoa de Meia-Idade
3.
BMC Musculoskelet Disord ; 25(1): 565, 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-39033138

RESUMO

INTRODUCTION: Growth plate damage in long bones often results in progressive skeletal growth imbalance and deformity, leading to significant physical problems. Gangliosides, key glycosphingolipids in cartilage, are notably abundant in articular cartilage and regulate chondrocyte homeostasis. This suggests their significant roles in regulating growth plate cartilage repair. METHODS: Chondrocytes from 3 to 5 day-old C57BL/6 mice underwent glycoblotting and mass spectrometry. Based on the results of the glycoblotting analysis, we employed GD3 synthase knockout mice (GD3-/-), which lack b-series gangliosides. In 3-week-old mice, physeal injuries were induced in the left tibiae, with right tibiae sham operated. Tibiae were analyzed at 5 weeks postoperatively for length and micro-CT for growth plate height and bone volume at injury sites. Tibial shortening ratio and bone mineral density were measured by micro-CT. RESULTS: Glycoblotting analysis indicated that b-series gangliosides were the most prevalent in physeal chondrocytes among ganglioside series. At 3 weeks, GD3-/- exhibited reduced tibial shortening (14.7 ± 0.2 mm) compared to WT (15.0 ± 0.1 mm, P = 0.03). By 5 weeks, the tibial lengths in GD3-/- (16.0 ± 0.4 mm) closely aligned with sham-operated lengths (P = 0.70). Micro-CT showed delayed physeal bridge formation in GD3-/-, with bone volume measuring 168.9 ± 5.8 HU at 3 weeks (WT: 180.2 ± 3.2 HU, P = 0.09), but normalizing by 5 weeks. CONCLUSION: This study highlights that GD3 synthase knockout mice inhibit physeal bridge formation after growth plate injury, proposing a new non-invasive approach for treating skeletal growth disorders.


Assuntos
Condrócitos , Gangliosídeos , Lâmina de Crescimento , Camundongos Endogâmicos C57BL , Camundongos Knockout , Animais , Lâmina de Crescimento/patologia , Lâmina de Crescimento/metabolismo , Gangliosídeos/metabolismo , Condrócitos/metabolismo , Camundongos , Desigualdade de Membros Inferiores , Tíbia/diagnóstico por imagem , Tíbia/patologia , Tíbia/metabolismo , Tíbia/crescimento & desenvolvimento , Microtomografia por Raio-X , Sialiltransferases/deficiência , Sialiltransferases/genética , Sialiltransferases/metabolismo , Modelos Animais de Doenças
4.
PeerJ ; 12: e17417, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38827307

RESUMO

Background: Osteoarthritis (OA) is a degenerative disease requiring additional research. This study compared gene expression and immune infiltration between lesioned and preserved subchondral bone. The results were validated using multiple tissue datasets and experiments. Methods: Differentially expressed genes (DEGs) between the lesioned and preserved tibial plateaus of OA patients were identified in the GSE51588 dataset. Moreover, functional annotation and protein-protein interaction (PPI) network analyses were performed on the lesioned and preserved sides to explore potential therapeutic targets in OA subchondral bones. In addition, multiple tissues were used to screen coexpressed genes, and the expression levels of identified candidate DEGs in OA were measured by quantitative real-time polymerase chain reaction. Finally, an immune infiltration analysis was conducted. Results: A total of 1,010 DEGs were identified, 423 upregulated and 587 downregulated. The biological process (BP) terms enriched in the upregulated genes included "skeletal system development", "sister chromatid cohesion", and "ossification". Pathways were enriched in "Wnt signaling pathway" and "proteoglycans in cancer". The BP terms enriched in the downregulated genes included "inflammatory response", "xenobiotic metabolic process", and "positive regulation of inflammatory response". The enriched pathways included "neuroactive ligand-receptor interaction" and "AMP-activated protein kinase signaling". JUN, tumor necrosis factor α, and interleukin-1ß were the hub genes in the PPI network. Collagen XI A1 and leucine-rich repeat-containing 15 were screened from multiple datasets and experimentally validated. Immune infiltration analyses showed fewer infiltrating adipocytes and endothelial cells in the lesioned versus preserved samples. Conclusion: Our findings provide valuable information for future studies on the pathogenic mechanism of OA and potential therapeutic and diagnostic targets.


Assuntos
Mapas de Interação de Proteínas , Humanos , Perfilação da Expressão Gênica , Osteoartrite/genética , Osteoartrite/imunologia , Osteoartrite/patologia , Osteoartrite do Joelho/genética , Osteoartrite do Joelho/imunologia , Osteoartrite do Joelho/patologia , Osteoartrite do Joelho/metabolismo , Masculino , Tíbia/patologia , Tíbia/imunologia , Tíbia/metabolismo , Regulação para Baixo , Feminino
5.
BMJ Case Rep ; 17(6)2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38871637

RESUMO

We present a case detailing the diagnosis and management of a periprosthetic giant cell tumour in a female patient in her 70s, who had undergone total knee arthroplasty (TKA) for primary osteoarthritis in her right knee 7 years prior. The patient reported 4 months of painful weight-bearing. Various imaging modalities, including plain radiographs, CT scans and MRI, revealed a sizeable lytic lesion beneath the TKA prosthesis, along with loosening of the tibial component.Blood tests and analyses of synovial fluid ruled out periprosthetic joint infection, and a biopsy confirmed the diagnosis of a giant cell tumour of the bone. Treatment entailed en bloc resection of the tumour and revision of the TKA using a hinged, oncological-type megaprosthesis. Surgical procedures involved careful resection of the proximal tibia, preservation of vasculature and the creation of a medial gastrocnemius muscle flap. Following surgery, the patient underwent supervised rehabilitation with a functional brace.


Assuntos
Artroplastia do Joelho , Neoplasias Ósseas , Tumor de Células Gigantes do Osso , Prótese do Joelho , Reoperação , Tíbia , Humanos , Feminino , Tíbia/cirurgia , Tíbia/patologia , Tíbia/diagnóstico por imagem , Artroplastia do Joelho/métodos , Tumor de Células Gigantes do Osso/cirurgia , Tumor de Células Gigantes do Osso/patologia , Tumor de Células Gigantes do Osso/diagnóstico por imagem , Neoplasias Ósseas/cirurgia , Neoplasias Ósseas/patologia , Idoso , Falha de Prótese
6.
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
7.
J Orthop Surg Res ; 19(1): 355, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38879553

RESUMO

BACKGROUND: The purpose of this study was to clarify (1) the differences in cortical bone thickness (CBT) of the tibial diaphysis between healthy and osteoarthritic knees and (2) the influences of the femorotibial angle (FTA) and inclination of the medial compartment of the proximal tibia (MCT) on tibial CBT. METHODS: The study assessed 60 subjects with varus knee osteoarthritis (OA) (22 males and 38 females; mean age, 74 ± 7 years) and 53 healthy elderly subjects (28 males and 25 females; mean age, 70 ± 6 years). Three-dimensional estimated CBT of the tibial diaphysis was automatically calculated for 2752-11,296 points using high-resolution measurements from CT. The standardized CBT was assessed in 24 regions by combining six heights and four areas. Additionally, the association between the CBT, each FTA, and MCT inclination was investigated. RESULTS: The OA group showed a thicker CBT in the medial areas than in the lateral areas of the proximal tibia, while the healthy group had a thicker lateral CBT. The medial-to-lateral ratio of the proximal tibia was significantly higher in the OA group than in the healthy group. The proximal-medial CBT correlated with FTA and MCT inclinations in the OA group. CONCLUSIONS: This study demonstrated that varus osteoarthritic knees showed a different trend of proximal-medial CBT with associations in FTA and MCT inclination from healthy knees, possibly due to medial load concentration.


Assuntos
Osso Cortical , Diáfises , Osteoartrite do Joelho , Tíbia , Humanos , Masculino , Feminino , Tíbia/diagnóstico por imagem , Tíbia/patologia , Idoso , Osteoartrite do Joelho/diagnóstico por imagem , Osteoartrite do Joelho/patologia , Osso Cortical/diagnóstico por imagem , Osso Cortical/patologia , Diáfises/diagnóstico por imagem , Diáfises/patologia , Idoso de 80 Anos ou mais , Tomografia Computadorizada por Raios X , Extremidade Inferior/diagnóstico por imagem , Pessoa de Meia-Idade
8.
J Control Release ; 372: 331-346, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38844176

RESUMO

Bone is one of the most prevalent sites of metastases in various epithelial malignancies, including breast cancer and this metastasis to bone often leads to severe skeletal complications in women due to its osteolytic nature. To address this, we devised a novel drug delivery approach using an Alendronate (ALN) functionalized self-assembled porous crystalsomes for concurrent targeting of Oleanolic acid (OA) and ALN (ALN + OA@NCs) to bone metastasis. Initially, the conjugation of both PEG-OA and OA-PEG-ALN with ALN and OA was achieved, and this conjugation was then self-assembled into porous crystalsomes (ALN + OA@NCs) by nanoemulsion crystallization. The reconstruction of a 3D single particle using transmission electron microscopy ensured the crystalline porous structure of ALN + OA@NCs, was well aligned with characteristic nanoparticle attributes including size distribution, polydispersity, and zeta potential. Further, ALN + OA@NCs showed enhanced efficacy in comparison to OA@NCs suggesting the cytotoxic roles of ALN towards cancer cells, followed by augmentation ROS generation (40.81%), mitochondrial membrane depolarization (57.20%), and induction of apoptosis (40.43%). We found that ALN + OA@NCs facilitated inhibiting osteoclastogenesis and bone resorption followed by inhibited osteolysis. In vivo activity of ALN + OA@NCs in the 4 T1 cell-induced tibia model rendered a reduced bone loss in the treated mice followed by restoring bone morphometric markers which were further corroborated bone-targeting effects of ALN + OA@NCs to reduce RANKL-stimulated osteoclastogenesis. Further, In vivo intravenous pharmacokinetics showed the improved therapeutic profile of the ALN + OA@NCs in comparison to the free drug, prolonging the levels of the drug in the systemic compartment by reducing the clearance culminating the higher accumulation at the tumor site. Our finding proposed that ALN + OA@NCs can effectively target and treat breast cancer metastasis to bone and its associated complications.


Assuntos
Alendronato , Neoplasias Ósseas , Nanopartículas , Osteólise , Tíbia , Alendronato/administração & dosagem , Alendronato/farmacocinética , Alendronato/química , Animais , Osteólise/prevenção & controle , Osteólise/tratamento farmacológico , Feminino , Nanopartículas/química , Nanopartículas/administração & dosagem , Tíbia/efeitos dos fármacos , Tíbia/patologia , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/secundário , Porosidade , Linhagem Celular Tumoral , Humanos , Conservadores da Densidade Óssea/administração & dosagem , Conservadores da Densidade Óssea/farmacocinética , Ácido Oleanólico/administração & dosagem , Ácido Oleanólico/farmacocinética , Ácido Oleanólico/química , Ácido Oleanólico/análogos & derivados , Camundongos Endogâmicos BALB C , Camundongos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia
9.
Bone ; 187: 117171, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38901788

RESUMO

Glucocorticoids (GCs) are the leading cause of secondary osteoporosis. The emerging perspective, derived primarily from 2D histological study of trabecular bone, is that GC-induced bone loss arises through the uncoupling of bone formation and resorption at the level of the basic multicellular unit (BMU), which carries out bone remodeling. Here we explore the impact of GCs on cortical bone remodeling in the rabbit model. Based upon the rapid reduction of bone formation and initial elevation of resorption caused by GCs, we hypothesized that the rate of advance (longitudinal erosion rate; LER) of cortical BMUs would be increased. To test this hypothesis we divided 20 female New Zealand White rabbits into four experimental groups: ovariohysterectomy (OVH), glucocorticoid (GC), OVH + GC and SHAM controls (n = 5 animals each). Ten weeks post-surgery (OVH or sham), and two weeks after the initiation of dosing (daily subcutaneous injections of 1.5 mg/kg of methylprednisolone sodium succinate in the GC-treated groups and 1 ml of saline for the others), the right tibiae were scanned in vivo using Synchrotron Radiation (SR) in-line phase contrast micro-CT at the Canadian Light Source. After an additional 2 weeks of dosing, the rabbits were euthanized and ex vivo images were collected using desktop micro-CT. The datasets were co-registered in 3D and LER was calculated as the distance traversed by BMU cutting-cones in the 14-day interval between scans. Counter to our hypothesis, LER was greatly reduced in GC-treated rabbits. Mean LER was lower in GC (4.27 µm/d; p < 0.001) and OVH + GC (4.19 µm/d; p < 0.001), while similar in OVH (40.13 µm/d; p = 0.990), compared to SHAM (40.44 µm/d). This approximately 90 % reduction in LER with GCs was also associated with an overall disruption of BMU progression, with radial expansion of the remodeling space occurring in all directions. This unexpected outcome suggests that GCs do not simply uncouple formation and resorption within cortical BMUs and highlights the value of the time-lapsed 4D approach employed.


Assuntos
Osso Cortical , Glucocorticoides , Tíbia , Microtomografia por Raio-X , Animais , Coelhos , Glucocorticoides/farmacologia , Feminino , Tíbia/efeitos dos fármacos , Tíbia/diagnóstico por imagem , Tíbia/patologia , Osso Cortical/efeitos dos fármacos , Osso Cortical/diagnóstico por imagem , Remodelação Óssea/efeitos dos fármacos
10.
Bone ; 186: 117167, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38876270

RESUMO

We evaluated the potential of sclerostin antibody (SclAb) therapy to enhance osseointegration of dental and orthopaedic implants in a mouse model (Brtl/+) mimicking moderate to severe Osteogenesis Imperfecta (OI). To address the challenges in achieving stable implant integration in compromised bone conditions, our aim was to determine the effectiveness of sclerostin antibody (SclAb) at improving bone-to-implant contact and implant fixation strength. Utilizing a combination of micro-computed tomography, mechanical push-in testing, immunohistochemistry, and Western blot analysis, we observed that SclAb treatment significantly enhances bone volume fraction (BV/TV) and bone-implant contact (BIC) in Brtl/+ mice, suggesting a normalization of bone structure toward WT levels. Despite variations in implant survival rates between the maxilla and tibia, SclAb treatment consistently improved implant stability and resistance to mechanical forces, highlighting its potential to overcome the inherent challenges of OI in dental and orthopaedic implant integration. These results suggest that SclAb could be a valuable therapeutic approach for enhancing implant success in compromised bone conditions.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Anticorpos , Colágeno Tipo I , Mutação , Osseointegração , Animais , Osseointegração/efeitos dos fármacos , Camundongos , Mutação/genética , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Anticorpos/farmacologia , Microtomografia por Raio-X , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/patologia , Peptídeos e Proteínas de Sinalização Intercelular , Implantes Dentários , Tíbia/diagnóstico por imagem , Tíbia/patologia , Tíbia/efeitos dos fármacos
11.
Sci Transl Med ; 16(753): eadj1597, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38924432

RESUMO

Congenital pseudarthrosis of the tibia (CPT) is a severe pathology marked by spontaneous bone fractures that fail to heal, leading to fibrous nonunion. Half of patients with CPT are affected by the multisystemic genetic disorder neurofibromatosis type 1 (NF1) caused by mutations in the NF1 tumor suppressor gene, a negative regulator of RAS-mitogen-activated protein kinase (MAPK) signaling pathway. Here, we analyzed patients with CPT and Prss56-Nf1 knockout mice to elucidate the pathogenic mechanisms of CPT-related fibrous nonunion and explored a pharmacological approach to treat CPT. We identified NF1-deficient Schwann cells and skeletal stem/progenitor cells (SSPCs) in pathological periosteum as affected cell types driving fibrosis. Whereas NF1-deficient SSPCs adopted a fibrotic fate, NF1-deficient Schwann cells produced critical paracrine factors including transforming growth factor-ß and induced fibrotic differentiation of wild-type SSPCs. To counteract the elevated RAS-MAPK signaling in both NF1-deficient Schwann cells and SSPCs, we used MAPK kinase (MEK) and Src homology 2 containing protein tyrosine phosphatase 2 (SHP2) inhibitors. Combined MEK-SHP2 inhibition in vivo prevented fibrous nonunion in the Prss56-Nf1 knockout mouse model, providing a promising therapeutic strategy for the treatment of fibrous nonunion in CPT.


Assuntos
Camundongos Knockout , Neurofibromina 1 , Proteína Tirosina Fosfatase não Receptora Tipo 11 , Pseudoartrose , Células de Schwann , Animais , Feminino , Humanos , Masculino , Camundongos , Diferenciação Celular/efeitos dos fármacos , Fibrose , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Neurofibromatose 1/patologia , Neurofibromatose 1/metabolismo , Neurofibromatose 1/complicações , Neurofibromina 1/metabolismo , Neurofibromina 1/genética , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 11/antagonistas & inibidores , Pseudoartrose/patologia , Pseudoartrose/metabolismo , Pseudoartrose/congênito , Células de Schwann/metabolismo , Células de Schwann/efeitos dos fármacos , Células de Schwann/patologia , Células-Tronco/metabolismo , Células-Tronco/efeitos dos fármacos , Tíbia/patologia
12.
Osteoarthritis Cartilage ; 32(9): 1149-1153, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38692504

RESUMO

OBJECTIVE: Understanding gender-specific differences in patterns of cartilage loss can improve our knowledge of the pathogenesis of knee osteoarthritis (KOA) development and progression and may inform clinical trials of treatments for KOA. The goal of our observational study was to examine gender differences in patterns of cartilage loss in the central weight-bearing regions of the femur. METHODS: We measured cartilage volume change in the indexed knee of 700 subjects with Kellgren-Lawrence 1, 2, or 3 from the Osteoarthritis Initiative for four follow-up periods (baseline [BL] to 24 mo, BL to 48 mo, BL to 72 mo, and BL to 96 mo) using the local area cartilage segmentation (LACS) method. Briefly, the LACS method uses robust coordinate systems fixed to anatomical landmarks to measure patterns of change in cartilage volume in sub-regions using responsiveness heat maps. RESULTS: We observed a statistically significant gender difference in cartilage change in the medial femur (MF), lateral femur (LF), and medial tibia. The heat maps showed loss was primarily in the posterior central weight-bearing portion of the LF and more general in the LT and MF. Similar patterns were observed for each of the four follow-up periods. CONCLUSIONS: The LACS method was capable of illustrating gender-specific differences in patterns of cartilage loss that may offer insight into the variation of gender differences in the natural history of KOA and may be useful in evaluating the benefit of interventions for KOA.


Assuntos
Cartilagem Articular , Fêmur , Osteoartrite do Joelho , Humanos , Feminino , Masculino , Osteoartrite do Joelho/patologia , Osteoartrite do Joelho/fisiopatologia , Cartilagem Articular/patologia , Cartilagem Articular/diagnóstico por imagem , Pessoa de Meia-Idade , Idoso , Fêmur/patologia , Fêmur/diagnóstico por imagem , Fatores Sexuais , Imageamento por Ressonância Magnética , Suporte de Carga/fisiologia , Articulação do Joelho/patologia , Progressão da Doença , Tíbia/patologia , Caracteres Sexuais
13.
Ann Biomed Eng ; 52(9): 2388-2402, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38744754

RESUMO

Bone tissue is subjected to increased mechanical stress during high-intensity work. Inadequate bone remodeling reparability can result in the continuous accumulation of microdamage, leading to stress fractures. The aim of this work was to investigate the characteristics and repair mechanisms of tibial microdamage under several degrees of overload. Also, we aimed at better understanding the effects of overload on the multi-scale structure and mechanical properties of bone. Sixty 5-month female rats were divided into three groups with different time points. Micro-CT was used to evaluate the three-dimensional microstructure, and three-point bending, quasi-static fracture toughness and creep mechanical test were carried out to evaluate the mechanical properties. SEM was used to observe the morphological characteristics of fracture surfaces. Section staining was used to count the microdamage parameters and numbers of osteoblasts and osteoclasts. The microarchitectures of cancellous and cortical bones in the three overload groups showed different degrees of damage. Overload led to a messy crystal structure of cortical bone, with slender microcracks mixed in, and a large number of broken fibers of cancellous bone. The properties associated with the elastic plasticity, fracture toughness, and viscoelasticity of cortical bone reduced in three groups, with that corresponding to day 30 presenting the highest damage. The accumulation of microdamage mainly occurred in the first 14 days, that is, the crack density peaked on day 14. Peak-targeted bone remodeling of cortical and cancellous bones occurred mainly between days 14 and 30. The influence of overload mechanical environment on bone quality at different time points was deeply investigated, which is of great significance for the etiology and treatment of stress fractures.


Assuntos
Remodelação Óssea , Ratos Sprague-Dawley , Tíbia , Animais , Tíbia/fisiopatologia , Tíbia/patologia , Feminino , Ratos , Estresse Mecânico , Microtomografia por Raio-X , Suporte de Carga , Força Compressiva
14.
Sci Rep ; 14(1): 12130, 2024 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-38802483

RESUMO

Distal femoral osteotomy (DFO) is performed alone or with high tibial osteotomy (HTO) for patients with osteoarthritis and distal femur deformities. DFO is technically demanding, particularly when creating an anterior flange. Herein, we examined the morphological characteristics of the distal femur based on the cortical shape as a surgical reference for biplanar DFO. Computed tomography images of 50 valgus and 50 varus knees of patients who underwent biplanar DFO or total knee arthroplasty were analyzed. Axial slices at the initial level of the transverse osteotomy in the DFO and slices 10 mm proximal and 10 mm distal to that level were selected. The medial and lateral cortical angles and heights (MCLA, LCLA, MCH, and LCH) were measured on axial slices. Statistical comparisons were performed between the medial and lateral cortices and valgus and varus knees. MCLA and MCH were significantly smaller and lower, respectively, than LCLA and LCH (P < 0.01). The MCLA and MCH of varus knees were significantly smaller and lower, respectively, than those of valgus knees (P < 0.01). Surgeons should carefully observe morphological differences in the distal femur cortex, distinguishing between medial and lateral knees and varus and valgus knees during the creation of the anterior flange in the DFO.


Assuntos
Fêmur , Osteotomia , Tomografia Computadorizada por Raios X , Humanos , Osteotomia/métodos , Fêmur/cirurgia , Fêmur/diagnóstico por imagem , Fêmur/anatomia & histologia , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Articulação do Joelho/cirurgia , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/patologia , Osteoartrite do Joelho/cirurgia , Osteoartrite do Joelho/diagnóstico por imagem , Osteoartrite do Joelho/patologia , Artroplastia do Joelho/métodos , Tíbia/cirurgia , Tíbia/diagnóstico por imagem , Tíbia/anatomia & histologia , Tíbia/patologia , Adulto
15.
Calcif Tissue Int ; 115(1): 78-84, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38753025

RESUMO

Subchondral bone remodeling, mediated by osteocytes within the lacuno-canalicular network, plays a crucial role in osteoarthritis (OA) progression. Following cell death, lacunae preserve integrity, offering insights into bone remodeling mechanisms. Limited and controversial data on osteocyte lacuna morphology in OA result from small sample sizes and two-dimensional (2D) techniques that have been used thus far. This study aimed to quantify three-dimensional (3D) osteocyte lacunar characteristics at well-defined tibial plateau locations, known to be differently affected by OA. Specifically, 11 tibial plateaus were obtained from end-stage knee-OA patients with varus deformity. Each plateau provided one sample from the less affected lateral compartment and two samples from the medial compartment, at minimum and maximum bone volume fraction (BV/TV) locations. High-resolution desktop micro-computed tomography (micro-CT) at 0.7 µm voxel resolution imaged the 33 samples. Lacuna number density (Lc.N/BV) and lacuna volume density (Lc.TV/BV) were significantly lower (p < 0.02) in samples from the medial side with maximum BV/TV compared to lateral side samples. In the medial compartment at maximum local BV/TV, mean lacuna volume (Lc.V), total lacuna volume (Lc.TV), and Lc.TV/BV were significantly (p < 0.001) lower than in the region with minimum BV/TV. Lc.N/BV was also significantly lower (p < 0.02) at the maximum local BV/TV location compared to the region with minimum BV/TV. Our findings suggest that subchondral bone lacunae adapt to the changing loads in end-stage OA.


Assuntos
Remodelação Óssea , Osteoartrite do Joelho , Osteócitos , Tíbia , Microtomografia por Raio-X , Humanos , Osteócitos/patologia , Tíbia/patologia , Tíbia/diagnóstico por imagem , Osteoartrite do Joelho/patologia , Osteoartrite do Joelho/diagnóstico por imagem , Masculino , Idoso , Feminino , Pessoa de Meia-Idade , Microtomografia por Raio-X/métodos , Remodelação Óssea/fisiologia
16.
BMJ Case Rep ; 17(5)2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38782438

RESUMO

SummaryGiant cell tumours of bone are benign and locally aggressive tumours that usually occur in young adults and at the epiphysial locations after physeal closure. Occurrence outside of epiphysial locations and appearance in geriatric patients is rare. We report a case of a woman in her late 60s with a giant cell tumour of the mid-shaft of the right tibia. Extended curettage and biological reconstruction were performed with autologous double-barrel fibular struts and tri-cortical iliac crest bone grafting. At the 28-month follow-up examination, we noted full bony union at both ends with successful consolidation of the fibular struts, and importantly, no evidence of recurrence or other complications was observed.


Assuntos
Neoplasias Ósseas , Tumor de Células Gigantes do Osso , Tíbia , Humanos , Feminino , Tíbia/diagnóstico por imagem , Tíbia/cirurgia , Tíbia/patologia , Neoplasias Ósseas/cirurgia , Neoplasias Ósseas/patologia , Neoplasias Ósseas/diagnóstico por imagem , Tumor de Células Gigantes do Osso/cirurgia , Tumor de Células Gigantes do Osso/patologia , Tumor de Células Gigantes do Osso/diagnóstico por imagem , Curetagem , Transplante Ósseo/métodos , Pessoa de Meia-Idade , Ílio/diagnóstico por imagem , Fíbula/diagnóstico por imagem , Fíbula/patologia , Fíbula/cirurgia , Diáfises/cirurgia , Resultado do Tratamento
17.
BMJ Case Rep ; 17(5)2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38782435

RESUMO

We present a novel case of a malignant transformation of an extremity soft tissue angioleiomyoma to leiomyosarcoma in a man in his late 70s who presented with a painful and increasing lump on his anterior tibia. Initial imaging and biopsy showed a benign angioleiomyoma which was excised for symptomatic reasons. An analysis of the resulting specimen revealed a 50×42×15 mm smooth muscle neoplasm consistent with angioleiomyoma with a 22×11 mm entirely intralesional nodular component in keeping with a grade 1 leiomyosarcoma. The malignant constituent of the lesion was entirely encased in benign angioleiomyoma negating the need for further surgery. Systemic staging investigation revealed no evidence of metastatic disease spread final staging as per the eighth edition of the American Joint Committee on Cancer (AJCC) Staging T1N0M0 R0 Stage 1 a.


Assuntos
Angiomioma , Leiomiossarcoma , Tíbia , Humanos , Masculino , Leiomiossarcoma/patologia , Leiomiossarcoma/cirurgia , Leiomiossarcoma/diagnóstico por imagem , Tíbia/patologia , Tíbia/diagnóstico por imagem , Angiomioma/patologia , Angiomioma/cirurgia , Angiomioma/diagnóstico por imagem , Idoso , Transformação Celular Neoplásica/patologia , Neoplasias de Tecidos Moles/patologia , Neoplasias de Tecidos Moles/cirurgia , Neoplasias de Tecidos Moles/diagnóstico por imagem , Biópsia , Neoplasias Ósseas/patologia , Neoplasias Ósseas/cirurgia , Neoplasias Ósseas/diagnóstico por imagem
18.
Int Orthop ; 48(9): 2439-2443, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38772936

RESUMO

PURPOSE: Managing the distal tibiofibular (DTF) joint remains a challenge despite recent developments. Ankle arthroscopy is emerging as a diagnostic and therapeutic means. Our study aimed to compare preoperative imaging data and arthroscopic data, with the hypothesis that imaging alone is insufficient to evaluate acute laxity, and with arthroscopy as the reference examination. METHODS: All patients treated in 2023 in our department for an acute isolated DTF lesion were included prospectively. Preoperative radiographic and MRI imaging were compared with arthroscopic data. RESULTS: Ten patients were treated. For five patients, the instability was doubtful after carrying out an appropriate imaging assessment (X-rays of both ankles, MRI). For four of these five patients, instability was confirmed by arthroscopy. Arthroscopy was useful for suturing the anterior bundle of the DTF joint for two patients and allowed for verifying the reduction in the sagittal and coronal planes for two patients. No complications were detected. CONCLUSIONS: Arthroscopy in isolated acute DTF lesions seems to provide a diagnostic and therapeutic advantage. Its use may allow for exhaustive assessment and complete repair of lesions. It must be offered as soon as possible; a delay in specialized imaging may delay therapeutic care.


Assuntos
Articulação do Tornozelo , Artroscopia , Instabilidade Articular , Imageamento por Ressonância Magnética , Humanos , Artroscopia/métodos , Masculino , Feminino , Adulto , Articulação do Tornozelo/cirurgia , Articulação do Tornozelo/diagnóstico por imagem , Articulação do Tornozelo/patologia , Imageamento por Ressonância Magnética/métodos , Instabilidade Articular/cirurgia , Instabilidade Articular/diagnóstico , Instabilidade Articular/diagnóstico por imagem , Estudos Prospectivos , Pessoa de Meia-Idade , Adulto Jovem , Traumatismos do Tornozelo/cirurgia , Traumatismos do Tornozelo/diagnóstico , Traumatismos do Tornozelo/diagnóstico por imagem , Fíbula/cirurgia , Fíbula/diagnóstico por imagem , Resultado do Tratamento , Radiografia/métodos , Adolescente , Tíbia/cirurgia , Tíbia/diagnóstico por imagem , Tíbia/patologia
19.
J Bone Miner Res ; 39(6): 707-716, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-38591788

RESUMO

Ultrashort echo time (UTE) MRI can quantify the major proton pool densities in cortical bone, including total (TWPD), bound (BWPD), and pore water (PWPD) proton densities, as well as the macromolecular proton density (MMPD), associated with the collagen content, which is calculated using macromolecular fraction (MMF) from UTE magnetization transfer (UTE-MT) modeling. This study aimed to investigate the differences in water and collagen contents in tibial cortical bone, between female osteopenia (OPe) patients, osteoporosis (OPo) patients, and young participants (Young). Being postmenopausal and above 55 yr old were the inclusion criteria for OPe and OPo groups. The tibial shaft of 14 OPe (72.5 ± 6.8 yr old), 31 OPo (72.0 ± 6.4 yr old), and 31 young subjects (28.0 ± 6.1 yr old) were scanned using a knee coil on a clinical 3T scanner. Basic UTE, inversion recovery UTE, and UTE-MT sequences were performed. Investigated biomarkers were compared between groups using Kruskal-Wallis test. Spearman's correlation coefficients were calculated between the TH DXA T-score and UTE-MRI results. MMF, BWPD, and MMPD were significantly lower in OPo patients than in the young group, whereas T1, TWPD, and PWPD were significantly higher in OPo patients. The largest OPo/Young average percentage differences were found in MMF (41.9%), PWPD (103.5%), and MMPD (64.0%). PWPD was significantly higher (50.7%), while BWPD was significantly lower (16.4%) in OPe than the Young group on average. MMF was found to be significantly lower (27%) in OPo patients compared with OPe group. T1, MMF, TWPD, PWPD, and MMPD values significantly correlated with the TH DXA T-scores (provided by the patients and only available for OPe and OPo patients). DXA T-score showed the highest correlations with PWPD (R = 0.55) and MMF (R = 0.56) values. TWPD, PWPD, and MMF estimated using the UTE-MRI sequences were recommended to evaluate individuals with OPe and OPo.


Ultrashort echo time (UTE) is an MRI technique that can quantify the water and collagen content of cortical bone. Water in the bone can be found residing in pores (pore water) or bound to the bone matrix (bound water). We investigated the differences in water and collagen contents of tibial cortical bone between female osteopenia patients, osteoporosis patients, and young participants. Bound water and collagen contents were significantly lower in osteoporosis patients than in the young group, whereas total water and pore water contents were significantly higher in osteoporosis patients. Pore water was significantly higher, while bound water was significantly lower in osteopenia than in the Young group. Collagen content was found to be significantly lower in osteoporosis patients compared with the osteopenia group. The estimated water and collagen contents were significantly correlated with the TH bone densitometry measures in the patients.


Assuntos
Doenças Ósseas Metabólicas , Colágeno , Imageamento por Ressonância Magnética , Osteoporose , Tíbia , Humanos , Feminino , Tíbia/diagnóstico por imagem , Tíbia/patologia , Tíbia/metabolismo , Osteoporose/diagnóstico por imagem , Osteoporose/metabolismo , Doenças Ósseas Metabólicas/diagnóstico por imagem , Doenças Ósseas Metabólicas/metabolismo , Adulto , Idoso , Colágeno/metabolismo , Pessoa de Meia-Idade , Osso Cortical/diagnóstico por imagem , Osso Cortical/patologia , Osso Cortical/metabolismo , Água/metabolismo , Porosidade
20.
Bone ; 185: 117111, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38679220

RESUMO

Chronic heavy alcohol consumption is a risk factor for low trauma bone fracture. Using a non-human primate model of voluntary alcohol consumption, we investigated the effects of 6 months of ethanol intake on cortical bone in cynomolgus macaques (Macaca fascicularis). Young adult (6.4 ± 0.1 years old, mean ± SE) male cynomolgus macaques (n = 17) were subjected to a 4-month graded ethanol induction period, followed by voluntary self-administration of water or ethanol (4 % w/v) for 22 h/d, 7 d/wk. for 6 months. Control animals (n = 6) consumed an isocaloric maltose-dextrin solution. Tibial response was evaluated using densitometry, microcomputed tomography, histomorphometry, biomechanical testing, and Raman spectroscopy. Global bone response was evaluated using biochemical markers of bone turnover. Monkeys in the ethanol group consumed an average of 2.3 ± 0.2 g/kg/d ethanol resulting in a blood ethanol concentration of 90 ± 12 mg/dl in longitudinal samples taken 7 h after the daily session began. Ethanol consumption had no effect on tibia length, mass, density, mechanical properties, or mineralization (p > 0.642). However, compared to controls, ethanol intake resulted in a dose-dependent reduction in intracortical bone porosity (Spearman rank correlation = -0.770; p < 0.0001) and compared to baseline, a strong tendency (p = 0.058) for lower plasma CTX, a biochemical marker of global bone resorption. These findings are important because suppressed cortical bone remodeling can result in a decrease in bone quality. In conclusion, intracortical bone porosity was reduced to subnormal values 6 months following initiation of voluntary ethanol consumption but other measures of tibia architecture, mineralization, or mechanics were not altered.


Assuntos
Consumo de Bebidas Alcoólicas , Calcificação Fisiológica , Osso Cortical , Macaca fascicularis , Animais , Masculino , Porosidade , Consumo de Bebidas Alcoólicas/fisiopatologia , Osso Cortical/efeitos dos fármacos , Osso Cortical/patologia , Osso Cortical/diagnóstico por imagem , Calcificação Fisiológica/efeitos dos fármacos , Fenômenos Biomecânicos/efeitos dos fármacos , Microtomografia por Raio-X , Tíbia/efeitos dos fármacos , Tíbia/diagnóstico por imagem , Tíbia/patologia , Etanol/farmacologia , Análise Espectral Raman , Densidade Óssea/efeitos dos fármacos
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