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1.
J Cell Mol Med ; 26(1): 60-74, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34854215

RESUMO

Recent evidence indicates that the abnormal differentiation of bone marrow-derived mesenchymal stem cells (BMSCs) plays a pivotal role in the pathogenesis of osteoporosis. LncRNA SNHG1 has been found to be associated with the differentiation ability of BMSCs. In this study, we aimed to elucidate the role of lncRNA SNHG1 and its associated pathway on the differentiation of BMSCs in osteoporosis. Mice that underwent bilateral ovariectomy (OVX) were used as models of osteoporosis. Induced osteogenic or adipogenic differentiation was performed in mouse BMSCs. Compared to sham animals, lncRNA SNHG1 expression was upregulated in OVX mice. Also, the in vitro expression of SNHG1 was increased in adipogenic BMSCs but decreased in osteogenic BMSCs. Moreover, overexpression of SNHG1 enhanced the adipogenic capacity of BMSCs but inhibited their osteogenic capacity as determined by oil red O, alizarin red, and alkaline phosphatase staining, while silencing of SNHG1 led to the opposite results. LncRNA SNHG1 interacting with the RNA-binding polypyrimidine tract-binding protein 1 (PTBP1) promoted osteoprotegerin (Opg) methylation and suppressed Opg expression via mediating DNA methyltransferase (DNMT) 1. Furthermore, Opg was showed to regulate BMSC differentiation. Knockdown of SNHG1 decreased the expressions of adipogenic related genes but increased that of osteogenic related genes. However, the knockdown of Opg partially reversed those effects. In summary, lncRNA SNHG1 upregulated the expression of DNMT1 via interacting with PTBP1, resulting in Opg hypermethylation and decreased Opg expression, which in turn enhanced BMSC adipogenic differentiation and contributed to osteoporosis.


Assuntos
Metilação de DNA , Células-Tronco Mesenquimais , Osteoprotegerina , RNA Longo não Codificante , Adipogenia/genética , Animais , Diferenciação Celular/genética , Células Cultivadas , DNA (Citosina-5-)-Metiltransferase 1 , Metilação de DNA/genética , Feminino , Ribonucleoproteínas Nucleares Heterogêneas/genética , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/fisiologia , Camundongos , Osteogênese/genética , Osteoprotegerina/genética , Osteoprotegerina/metabolismo , Proteína de Ligação a Regiões Ricas em Polipirimidinas , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo
2.
Mol Med ; 27(1): 141, 2021 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-34732133

RESUMO

BACKGROUND: We aimed to investigate the functions and underlying mechanism of lncRNA SNHG1 in bone differentiation and angiogenesis in the development of osteoporosis. METHODS: The differential gene or proteins expressions were measured by qPCR or western blot assays, respectively. The targeted relationships among molecular were confirmed through luciferase reporter, RIP and ChIP assays, respectively. Alkaline phosphatase (ALP), alizarin red S (ARS) and TRAP staining were performed to measure the osteoblast/osteoclast differentiation of BMSCs. The viability, migration and angiogenesis in BM-EPCs were validated by CCK-8, clone formation, transwell and tube formation assays, respectively. Western blot and immunofluorescence detected the cytosolic/nuclear localization of ß-catenin. Ovariectomized (OVX) mice were established to confirm the findings in vitro. RESULTS: SNHG1 was enhanced and miR-181c-5p was decreased in serum and femoral tissue from OVX mice. SNHG1 directly inhibited miR-181c-5p to activate Wnt3a/ß-catenin signaling by upregulating SFRP1. In addition, knockdown of SNHG1 promoted the osteogenic differentiation of BMSCs by increasing miR-181c-5p. In contrast, SNHG1 overexpression advanced the osteoclast differentiation of BMSCs and inhibited the angiogenesis of BM-EPCs, whereas these effects were all reversed by miR-181c-5p overexpression. In vivo experiments indicated that SNHG1 silencing alleviated osteoporosis through stimulating osteoblastogenesis and inhibiting osteoclastogenesis by modulating miR-181c-5p. Importantly, SNHG1 could be induced by SP1 in BMSCs. CONCLUSIONS: Collectively, SP1-induced SNHG1 modulated SFRP1/Wnt/ß-catenin signaling pathway via sponging miR-181c-5p, thereby inhibiting osteoblast differentiation and angiogenesis while promoting osteoclast formation. Further, SNHG1 silence might provide a potential treatment for osteoporosis.


Assuntos
Remodelação Óssea/genética , MicroRNAs , Osteoporose/genética , RNA Longo não Codificante , Fator de Transcrição Sp1/genética , Animais , Diferenciação Celular , Células Cultivadas , Feminino , Proteínas de Membrana/metabolismo , Camundongos Endogâmicos C57BL , Neovascularização Fisiológica , Transdução de Sinais , Células-Tronco/citologia , Proteína Wnt3A/metabolismo
3.
Mol Cell Biochem ; 438(1-2): 175-182, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28766166

RESUMO

To investigate the mechanism of recombinant human platelet-derived growth factor-BB (rhPDGF-BB) and human adipose-derived stem cells (hADSCs) in the treatment of Achilles tendinitis. Biomechanical indices of stiffness, stress, and maximum load-to-failure were detected by biomechanical test. mRNA and protein levels of miR-363, p-PI3K/AKT, tendon-related genes Collagen I, Scleraxis (Scx), and Tenascin C (TNC) were measured by qRT-PCR and western blot. The proliferation of hADSCs was accessed by MTT assay. Biomechanical indices of stiffness, stress, and maximum load-to-failure, and mRNA and protein levels of tendon-related genes could be improved by rhPDGF-BB or hADSCs alone, and could be further improved by rhPDGF-BB + hADSCs. rhPDGF-BB and hADSCs downregulated the expression of miR-363 and upregulated the levels of p-PI3K/Akt, and rhPDGF-BB + hADSCs further strengthened these effects. In addition, rhPDGF-BB promoted the proliferation of hADSCs in vitro and upregulated the expression of tendon-related genes. miR-363 mimic downregulated the levels of p-PI3K/Akt, miR-363 inhibitor upregulated the levels of p-PI3K/Akt, and miR-363 mimic and PI3K/Akt pathway inhibitor LY294002 reversed the positive effect of rhPDGF-BB on the proliferation of hADSCs, which suggested that rhPDGF-BB promoted the proliferation of hADSCs via miR-363/PI3K/Akt pathway. Biomechanical indices and tendon-related genes could be improved by rhPDGF-BB and hADSCs. Moreover, rhPDGF-BB promoted the proliferation of hADSCs via miR-363/PI3K/Akt pathway, indicating that rhPDGF-BB combined with ADSCs could treat Achilles tendinitis via miR-363/PI3K/Akt pathway.


Assuntos
Tendão do Calcâneo , Tecido Adiposo/metabolismo , Proteínas Proto-Oncogênicas c-sis/farmacologia , Transplante de Células-Tronco , Células-Tronco/metabolismo , Tendinopatia/terapia , Tecido Adiposo/patologia , Animais , Becaplermina , Modelos Animais de Doenças , Xenoenxertos , Humanos , Ratos , Ratos Sprague-Dawley , Células-Tronco/patologia , Tendinopatia/metabolismo , Tendinopatia/patologia
4.
BMC Musculoskelet Disord ; 19(1): 282, 2018 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-30086737

RESUMO

BACKGROUND: Steroids such as glucocorticoid have been widely used for their excellent anti-inflammatory, anti-immune, and anti-shock properties. However, the long-term use in high doses has been found to cause necrosis of femoral head and other serious adverse reactions. Thus, it is of great importance to safely use these medications on patients without inducing bone necrosis. METHODS: In this preclinical study, we examined the effects of erythropoietin (EPO) to attenuate the induction of steroid-induced femoral bone necrosis using rats to build up the in-vivo models. Rats were randomly divided into three groups: negative control group (group A), disease group (group B), and EPO group (group C). 20 mg/kg methylprednisolone was administrated into group B and group C for 6 weeks with two intramuscular injections per week per rat. Group C was further given daily intraperitoneal injections of rHuEPO during this period. Group A received only injection of saline at the same schedule. 12 weeks after the initial drug administration, the rats' femoral tissues were harvested for HE staining, immunohistochemistry studies for PECAM-1(also CD31) expression and Western Blotting for VEGF expression. RESULTS: Histology studies showed that compared with the disease group, EPO group had significant improvement and bone morphology being much closer to the negative control group. Immunohistochemical studies revealed that EPO group had statistically much more expression of PECAM-1 than the other groups did. Western Blot demonstrated that the EPO group had significantly higher VEGF expression than the disease group. CONCLUSION: Results suggested that simultaneous injection of EPO could partially prevent steroid-induced ANFH.


Assuntos
Eritropoetina/farmacologia , Necrose da Cabeça do Fêmur/prevenção & controle , Cabeça do Fêmur/efeitos dos fármacos , Metilprednisolona , Animais , Modelos Animais de Doenças , Feminino , Cabeça do Fêmur/metabolismo , Cabeça do Fêmur/patologia , Necrose da Cabeça do Fêmur/induzido quimicamente , Necrose da Cabeça do Fêmur/metabolismo , Necrose da Cabeça do Fêmur/patologia , Masculino , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Ratos Sprague-Dawley , Fator A de Crescimento do Endotélio Vascular/metabolismo
5.
Pak J Med Sci ; 33(1): 146-150, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28367189

RESUMO

OBJECTIVES: To study the influence of forefoot plantar pressure of the first tarsometatarsal joint fracture-dislocation by three different implants to provide experimental reference in selecting implants. METHODS: Eight fresh foot specimens were made into the models of the first tarsometatarsal joint fracture-dislocation, which were fixed with 3.5 mm cortical screw, 1/4 tubular plate and compressive staple in turn. After the loading of 600N, the changes of the plantar pressure in forefoot were measured by the method of the F-scan plantar pressure system. RESULTS: After first tarsometatarsal joint fracture-dislocation, the peak pressure under the first metatarsal head would decrease, while the pressure under the second metatarsal head would increase(P<0.05). When the first tarsometatarsal joint was fixed with screw or plate respectively; the peak pressure under the two metatarsal heads would tend to be normal. However, the staple fixation would show the statistical significant difference, although the peak pressure under the first and second metatarsal heads were recovered in some extent(P<0.05). CONCLUSIONS: After the first tarsometatarsal joint fracture-dislocation, the plantar pressure might be compensated partly by the adjacent metatarsal heads. While the first tarsometatarsal joint fracture-dislocation was fixed by screw or plate, the plantar pressure of the forefoot would return to the normal state. However, if the joint was fixed by the staple, it would still be difficult to return the plantar pressure to be normal.

6.
Pak J Med Sci ; 33(3): 650-653, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28811788

RESUMO

OBJECTIVE: To summarize the clinical results of femoral head fracture-dislocation treated according to Pipkin classification. METHODS: Atotal of 19 patients with femoral head fracture-dislocation were retrospectively analyzed from Mar. 2008 to Mar. 2015. According to the classification of Pipkin criteria, there were 4 cases in Type-I, 6 cases in Type-II, 6 cases in Type-IIIand 3 cases in Type-IV. Various procedures were taken according to the different types of the fracture, the time of the fracture, and the age of the patients. X-ray was examined during the follow-up period and functional evaluation was carried out by Harris Hip Score's criteria. The clinical therapeutic effects were analyzed. RESULTS: All the patientsgot a mean follow-up of 18 months (9-36 months). No patient suffered from infection, skin flap necrosis and X-ray showed no implants loosening or breakage. According to the Harris Hip Score's criteria, in Type-I, 4 cases were rated as excellent. In Type-II, 2 cases rated as excellent, 3 cases as good and 1 case as fair. In Type-III, 3 cases rated as good, 2 cases as fair and 1 case as poor. In Type-IV, 1 case rated as excellent, 1 case as good and 1 case as fair. The overall rate of excellent and good was 73.7%. CONCLUSIONS: Pipkin classification is helpful to make preoperative plan and judging the prognosis in cases of femoral head fracture-dislocation. However, multiple factors such as the time from injury to surgery, the ages of patients, the selection of implants should also be considered, which may affect the clinical results.

7.
Pak J Med Sci ; 30(5): 1099-103, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25225534

RESUMO

OBJECTIVE: In the surgery of calcaneal fracture, whether the sustentaculum tali screw should always be placed is widely controversial. The aim of this study was to explore the necessity and function of the sustentaculum tali screw placement for the treatment of Sanders type II calcaneal fracture. METHODS: The finite element analysis was used in this study. After the establishment of the finite element model of Sanders type II calcaneal fracture, the two internal fixation simulations were designed. In one model, the AO calcaneal plate was simulated on the lateral side of the calcanues with 7 screws being fixated at different position of the plate. In the other model, the calcaneus was fixated with the same AO calcaneal plate together with an additional screw being infiltrated into the sustentaculum tali. The two models were simulated under the same loading and the displacement of the fracture line and the stress distribution in the two models were calculated respectively. RESULTS: The maximum principal stress focused on the cortical bone of sustentaculum tali in both the models under the same loading. The displacement of the fracture line, the maximum principal stress of calcaneus and internal fixation system in the model with sustentaculum screw fixation were smaller than that in the model without sustentaculum screw fixation. The stress in the model with sustentaculum screw fixation was more dispersed. CONCLUSIONS: The placement of sustentaculum tali screw is essential for fixation of type II calcaneal fracture to achieve the biomechanical stability.

8.
Pak J Med Sci ; 30(4): 773-7, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25097515

RESUMO

Objective : To summarize the functional outcome of tarsometatarsal joint fracture-dislocation managed according to Myerson classification. Methods : Total eighty cases of tarsometatarsal joint fracture-dislocation were treated from Mar 2004 to Feb 2012. According to the Myerson classification, there were 14 cases in type A, 12 cases in type B1, 28 cases in type B2, 11 cases in type C1 and 15 cases in type C2. All the cases were treated with open reduction and internal fixation and the incisions and implants were also selected according to the Myerson classification. X-ray was examined during the follow-up period and functional evaluation was carried out by American Orthopaedic Foot and Ankle Society (AOFAS) midfoot score system. Analysis of variance was used to test the different types of Myerson classification. Results : Sixty eight patients got a mean follow-up of 24 months (15-36 months). No patient suffered from infection, skin flap necrosis and X-ray showed there were no implants loosening or breakage. The mean AOFAS score was 88.4(47-100) and excellent and good result was 89.7%. The differences among Myerson classifications showed that there were statistical significance between type B and type A, type C (P<0.05) Three patients suffered from severe pain and difficult walking, X-ray showed the ambiguity of the joint space, which can be diagnosed as posttraumatic arthritis. One patient had arthrodesis finally. Conclusion : The Myerson classification is helpful to make preoperative plan and judging prognosis to the tarsometatarsal joint injuries. In type B, single or double incisions with screw or plate fixation is enough, while in type A and type C, double or triple incisions with screw or plate fixation in medial joints and Kirschner wire fixation in lateral joints are needed. Postoperatively, the type B patients had better prognosis than type A and type C patients. However, the concomitant injuries around the tarsometatarsal joint were not included in Myerson classification, which is the limitation but cannot be neglected.

9.
Zhongguo Gu Shang ; 37(5): 476-81, 2024 May 25.
Artigo em Zh | MEDLINE | ID: mdl-38778531

RESUMO

OBJECTIVE: To investigate the occurrence of posterior femoral head tilt after clinical non-displaced femoral neck fracture, and to provide a reference basis for clinical surgery and improvement of disease prognosis. METHODS: Total of 165 patients with non-displaced femoral neck fractures of Garden typeⅠandⅡfrom January 2018 to June 2022 were selected as study subjects including 48 males and 117 females, with an average age of (71.5±8.5) years old ranging from 53 to 89, involving 97 cases of typeⅠand 68 of typeⅡ. On the patient's preoperative sagittal or axial CT film of the hip, the angle formed by the radius line of the femoral head and the midline of the femoral neck was used as the posterior tilt angle of the femoral head (α), and the posterior tilt femoral head angle was measured using the method proposed by Palm. The measured data were divided into 6 groups:α<0°, 0°<α< 5°, 5°≤α<10°, 10°≤α<15°, 15°≤α<20°, α≥20°, and the incidence of different ranges of posterior tilt angle was compared. The sex composition ratio of 165 patients were analyzed and compared, and the age of 65 was used as the cut-off point to compare the incidence of fractures between genders. Patients were divided into the posterior tilt <20° group for 135 cases and the posterior tilt ≥20°group for 30 cases according to the preoperative posterior tilt angle, the differences between two groups in terms of gender and age were analyzed. RESULTS: Among 165 patients with non-displaced femoral neck fractures, 143 cases with poaterior tilt of the femoral head occurred with an incidence of 86.7%. Posterior tilt 0°<α<5° accounted for 36 cases with an incidence of 21.8%;5°≤α<10° accounted for 40 cases with an incidence of 24.2%;10°≤α<15° accounted for 27 cases with an incidence of 16.4%;15°≤α<20° accounted for 10 cases with an incidence of 6.1%;posterior tilt angle α≥20° accounted for 30 cases, the incidence was 18.2%, of which the maximum posterior tilt angle was 42.7°. Statistical analysis showed that the percentage of fractures in the 165 patients selected for this study was significantly higher in female than in male, and that the female group was more likely to have fractures before the age of 65 years compared to the male group. However, gender, age and fracture subtypes (GardenⅠ, Ⅱ) were not influential factors for femoral neck fractures with a preoperative posterior femoral head tilt angle >20°(P>0.05). CONCLUSION: The incidence of femoral head posterior tile in non-displaced femoral neck fractures is relatively high, in which severe posterior tile occurs, and the femoral head posterior tile angle≥20° can reach 18.2%. In patients with closed reduction internal fixation, the fracture end needs to be repositioned as much as possible to reduce the risk of postoperative avascular necrosis of the femoral head. In order to prevent femoral neck fractures, special attention should be paid to anti-osteoporosis treatment for female. Preoperative assessment of posterior tilt is critical for patients of different ages, genders and fracture subtypes (GardenⅠ, Ⅱ).


Assuntos
Fraturas do Colo Femoral , Cabeça do Fêmur , Humanos , Masculino , Feminino , Fraturas do Colo Femoral/cirurgia , Idoso , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Incidência , Tomografia Computadorizada por Raios X
10.
Pak J Med Sci ; 29(2): 687-92, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24353608

RESUMO

The surgical management to the injuries of the fourth and fifth tarsometatarsal (TMT) joints is controversial. We briefly review the anatomical characteristics to the injuries, the diagnosis, as well as the individualized treatment of the injuries of the fourth and fifth TMT joints by open reduction and internal fixation, TMT arthrodesis and arthroplasty. We conclude that open reduction and internal fixation is the recommended option for acute injuries, while arthrodesis can be used in cases of malunion of the fourth and fifth TMT joints with gross pain or arthritic changes and obvious structural deformity. Arthroplasty is an effective salvage operation mainly used in high-demand patients with severe TMT arthritis. Finally, we propose a recommended treatment algorithm (based on the literature and our experience), taking into account the specific indications for internal fixation, TMT arthrodesis and arthroplasty to optimize the individualized treatment. Data sources/Study selection Data from survey reports, descriptive, cross-sectional and longitudinal studies published from 2002 to 2012 on the topic of the injuries to the fourth and fifth tarsometatarsal joint on human and radiography studies were included. Data Extraction The data was extracted from online resources of American Orthopaedic Foot & Ankle Society, American Academy of Orthopaedic Surgeons, US National Library of Medicine, The MEDLINE. Conclusion It is important to comprehend the specific anatomical characteristics and grasp the strict indications, advantages and disadvantages of the ORIF, TMT arthrodesis and arthroplasty to optimize the individualized treatment of the fourth and fifth TMT joints injuries in a maximum extent.

11.
Pak J Med Sci ; 29(1): 191-6, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24353538

RESUMO

OBJECTIVE: To explore the treatment strategies and clinical effect of the acetabular malunion with traumatic arthritis by total hip arthroplasty. METHODOLOGY: A retrospective analysis was conducted on 47 cases of acetabular malunion with traumatic arthritis from June 2000 to December 2009. All the patients underwent total hip arthroplasty with bone grafting or titanium cage for bone defect of the acetabulum. Harris hip scoring system was used for evaluating the functional recovery of the hip joint. RESULTS: Thirty three cases had an average of 47 months follow-up. No prosthesis was loosened and the function of hip joint was improved obviously with the Harris hip scores improving from 43.5 to 87.6. However, there were one case of sciatic nerve injury and four cases of heterotopic ossification postoperatively. CONCLUSION: Total hip arthroplasty might be an effective treatment of acetabular malunion with traumatic arthritis. Proper evaluation and reasonable reconstruction of acetabular defect as well as reasonable selection of prosthesis are essential to obtain an excellent outcome.

12.
Zhongguo Gu Shang ; 36(10): 969-74, 2023 Oct 25.
Artigo em Zh | MEDLINE | ID: mdl-37881931

RESUMO

There are still many unresolved problems in the treatment and prognosis of nondisplaced femoral neck fractures, such as nonunion and avascular necrosis of the caput femoris .In order to reduce the risk of various complications after non-displaced femoral neck fractures, the caput femoris posterior tilt of femoral neck fractures and its impact on prognosis have attracted more and more attention. A large number of scholars' studies have found that when the posterior tilt exceeds 20°, the risk of internal fixation failure increases significantly. Based on this concept, we can choose to use primary artificial joint replacement instead of three-screw internal fixation according to the different posterior tilt angles of patients to reduce the incidence of postoperative complications. At the same time, our analysis found that comminution of the posterior segment of the femoral neck would lead to an increase in the posterior inclination angles. The purpose of this review was to investigate the relationship between caput femoris posterior tilt of femoral neck fractures and surgical outcome, and to introduce a new method for measuring caput femoris posterior tilt of the femoral neck.


Assuntos
Fraturas do Colo Femoral , Complicações Pós-Operatórias , Humanos , Prognóstico , Complicações Pós-Operatórias/epidemiologia , Fraturas do Colo Femoral/cirurgia , Fraturas do Colo Femoral/complicações , Colo do Fêmur , Reoperação , Fixação Interna de Fraturas/métodos , Estudos Retrospectivos
13.
Zhongguo Gu Shang ; 35(11): 1042-8, 2022 Nov 25.
Artigo em Zh | MEDLINE | ID: mdl-36415189

RESUMO

OBJECTIVE: To propose the an optimal screw placement scheme to prevent femoral neck shortening, finite element analysis was used to evaluate the biomechanical outcome of different numbers formed by full threaded screws at different positions in the treatment of femoral neck fractures of Pauwels type Ⅱ. METHODS: Recruited for this study was a 55-year-old female volunteer with a weight of 70 kg and a height of 165 cm. CT scan data of her right femur was collected. The models of femoral of Pauwels typeⅡ and fully threaded screw(FTS) and partially threaded screw(PTS) were constructed in three-dimensional modeling software. All these screw placement schemes were divided into eight groups simulated the inverted triangular configuration:three PTSs, an anterosuperior FTS and two PTSs, a posterosuperior FTS and two PTSs, an inferior FTS and two PTSs, an anterosuperior PTS and two FTSs, a posterosuperior PTS and two FTSs, an inferior PTS and two FTSs and three FTSs. All fracture internal fixation models were processed in finite element analysis software. Parameters of postoperative femoral neck length, displacement distribution and peak displacement of screws and VonMises stress distribution and peak stress of screws, the proximal femur and fracture section were collected. RESULTS: The maximum VonMises stress of screws was 239.71, 213.44, 199.37, 230.82, 201.63, 215.72, 185.65 and 192.64 MPa, respectively, which was concentrated in the inferior screw near the fracture line. The maximum Von Mises stress of the proximal femur was 269.48, 241.62, 249.43, 269.69, 271.60, 346.64, 236.97 and 439.62 MPa, respectively, which was concentrated in the inferior medial area of subtrochanteric femur. The maximum Von Mises stress of fracture section was 149.12, 143.04, 140.47, 139.63, 139.81, 130.07, 117.77 and 57.89 MPa, respectively, which was concentrated around the partially threaded screw channel instead of the fully threaded screw channel. The maximum displacement of screws was 5.52, 5.43, 5.32, 5.17, 5.05, 5.13, 5.28 and 5.04 mm, respectively, which was along the axis of the femoral neck, and the displacement distribution was concentrated on the tip of the screw. The length of postoperative femoral neck length was 74.69, 74.72, 74.70, 74.70, 74.72, 74.70, 74.72 and 74.74 mm, respectively. CONCLUSION: The placement of one anterosuperior partially threaded screw and two fully threaded screws with an inverted triangular distribution can not only meet the sliding compression effect to promote femoral neck healing and ensure the stability of the proximal femur, but also reduce the degree of postoperative femoral neck shortening and reduce the incidence of hip joint dysfunction. This study provides a new optimal screw placement solution for the treatment of femoral neck fractures.


Assuntos
Fraturas do Colo Femoral , Fixação Interna de Fraturas , Feminino , Humanos , Pessoa de Meia-Idade , Parafusos Ósseos , Fraturas do Colo Femoral/cirurgia , Colo do Fêmur , Análise de Elementos Finitos , Software
14.
Zhongguo Gu Shang ; 34(6): 584-8, 2021 Jun 25.
Artigo em Zh | MEDLINE | ID: mdl-34180182

RESUMO

Parathyroid hormone is one kind of osteoanabolic agents widely used in clinic for osteoporosis. However, parathyroid hormone needs to be further optimized in the treatment of osteoporosis due to its two way regulatory effect of bone formation with low-dose intermittent treatmentand bone resorption with high-dosecontinuous treatment. Hence, based on the molecular mechanism of parathyroid hormone regulating bone metabolism, we conclude that parathyroid hormone regulates bone metabolism mainly through the following signaling pathways: (1) Gs/cAMP/PKA signaling pathway, whichis the main mechanism of parathyroid hormone regulating bone metabolism to lead to bone formation or bone resorption. (2) Gq/11/PLC/PKC signaling pathway, whose f_6_main function is to inhibit osteogenesis.(3)nonPLC/PKC signaling pathway, which is considered to playosteogenic effect, but whose specific content is not completely clear. (4) ß-arrestin signaling pathway, which can only induceosteogenesis without osteoclastic activation byreceptor desensitization and endocytosis. In this work, we will review the specific contents and functions of the four main signaling pathways activated by parathyroid hormoneto find more optimalosteoanabolic agents. Among them, SOST and Dickkopf-1 monoclonal antibodies are novel targeted drugs. Parathyroid hormone-related peptide that specifically activates the nonPLC/PKC signaling pathway or ß-arrestin signaling pathway is worthy of further development and application.


Assuntos
Reabsorção Óssea , Osteoporose , Humanos , Osteogênese , Hormônio Paratireóideo , Transdução de Sinais
15.
Biomed Res Int ; 2021: 3490881, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34395612

RESUMO

OBJECTIVE: To evaluate the stress status of fracture site caused by femoral neck shortening and to analyze the stress of fracture site and the implants from the finite element point of view. METHODS: CT scan data of hip of a normal adult female were collected. Three-dimensional reconstruction MICs and related module function simulation was used to establish the postoperative shortening model of femoral neck fracture with Pauwels angle > 50°, which was treated with cannulated screws. The models were divided into four groups: normal femoral neck, shortening in 2.5 mm, shortening in 7.5 mm, and shortening in 12.5 mm. The finite element analysis software msc.nastran2012 was used, and the data of maximum stress and stress nephogram of fracture site and implants were carried out. RESULTS: From normal femoral neck to shortening in 12.5 mm of the femoral neck, the maximum tensile stress increased gradually in the fracture site above the cannulated screws while compressive stress decreased gradually in the fracture site below the cannulated screws, and the maximum stress of the cannulated screws increased gradually with obvious stress concentration at the screw holes in the fracture site, and the peak value of stress concentration was about 179 MPa. CONCLUSION: The biomechanical environment of the fracture site changed by femoral neck shortening. With the increasing of femoral neck shortening, the stress of the fracture site and implants would be uneven; then, the stability of fracture site would become worse, and the possibility of implant sliding or even breakage would be increased.


Assuntos
Fraturas do Colo Femoral/cirurgia , Fixação Interna de Fraturas/instrumentação , Consolidação da Fratura , Osteoporose Pós-Menopausa/complicações , Fenômenos Biomecânicos , Parafusos Ósseos , Feminino , Fraturas do Colo Femoral/etiologia , Análise de Elementos Finitos , Humanos , Pessoa de Meia-Idade , Modelos Anatômicos , Osteoporose Pós-Menopausa/cirurgia , Pressão
16.
Zhongguo Gu Shang ; 34(2): 137-42, 2021 Feb 25.
Artigo em Zh | MEDLINE | ID: mdl-33666000

RESUMO

OBJECTIVE: To explore biomechanical characteristics of minimally invasive different screw fixations in treating Sanders typeⅡcalcaneal fractures. METHODS: Dicom data of calcaneus by CT scan were input into Mimics 21.0 software and Ansys15.0 software to construct three-dimensional finite element digital model of calcaneus;this model was input into UG NX 10.0 software, and calcaneus was cut according to Sanders classification to establish Sanders typeⅡ calcaneus model with posterior articular surface collapse;then simulated minimally invasive screw internal fixation after calcaneal fracture:a screw from posterior articular surface was used to outside-in fix sustentaculum tali, other 4 screws were used to fix calcaneus by different methods through calcaneal tuberosity, and 4 different calcaneal models were obtained. Under the same conditions, 4 types of internal fixation models were loaded respectively, and nonlinear finite element analysis was performed to calculate the stress distribution of different internal fixation models. RESULTS: Under the same condition of loading, the model 3 had smaller displacement value, maximum calcaneus displacement value and maximum equivalent stress value of the screw than other three internal fixation models, and the stress was more dispersed. CONCLUSION: In minimally invasive screw internal fixation of calcaneus fracture, after 1 sustentaculum tali screw fixation, 2 screws crossed fix posterior articular surface from calcaneal tuberosity, 2 screws fix parallelly calcaneocuboid joint from calcaneal tuberosity are more suitable for biomechanical requirements, and could provide basic theory for clinical treatment.


Assuntos
Calcâneo , Fraturas Ósseas , Parafusos Ósseos , Calcâneo/cirurgia , Análise de Elementos Finitos , Fixação Interna de Fraturas , Fraturas Ósseas/cirurgia , Humanos , Resultado do Tratamento
17.
Zhonghua Yi Xue Za Zhi ; 90(13): 890-3, 2010 Apr 06.
Artigo em Zh | MEDLINE | ID: mdl-20646507

RESUMO

OBJECTIVE: To introduce a new C(1) screw insertion technique to avoid injury to C(1-2) venous sinus in posterior atlantoaxial fixation. METHODS: 48 cases (96 sides of C(1) screws) undergoing posterior atlantoaxial fixation were retrospectively analyzed, including 28 cases of C(1) or C(2) fresh fracture and 20 cases of congenital malformation or old fracture & dislocation, among which 12 cases (24 sides) were operated by Goel lateral mass screws, 14 cases (28 sides) by TAN Mingsheng C(1) transpedicular screws and 44 sides of C(1) screws in 22 cases were inserted via notch on underside of C(1) posterior arch combined with bone wax column protecting C(1-2) venous sinus. RESULTS: Bleeding was encountered in five sides of C(1) screws among 26 cases (52 sides) whose venous sinuses were not protected by bone wax column, involving 3 cases of Goel lateral screw implant fixation. There was statistical difference in the incidence rate of bleeding between Goel technique and ours (P < 0.05) while there was no statistical difference between C(1) transpedicular technique and ours (P > 0.05) or between Goel sides of Goel lateral mass screws (12.5%) and 2 sides of C(1) transpedicular screws (7.1%). It occurred in none of 22 cases (44 sides) with our presented technique. There was a significant difference between Goel lateral screw implant fixation and C(1) transpedicular technique (P > 0.05). All the screws were implanted successfully. All cases were followed up and there was not any sign of implant failure. CONCLUSIONS: Our presented C(1) screw insertion technique can provide a better bony landmark and vascular protection, stronger bony holding power and more extensive applicability to reduce injury to C(1-2) venous sinus and increase the surgical safety.


Assuntos
Articulação Atlantoaxial/cirurgia , Parafusos Ósseos , Veias Jugulares , Adulto , Idoso , Vértebras Cervicais/irrigação sanguínea , Feminino , Humanos , Fixadores Internos , Masculino , Pessoa de Meia-Idade , Segurança , Resultado do Tratamento
18.
Zhongguo Gu Shang ; 33(8): 776-83, 2020 Aug 25.
Artigo em Zh | MEDLINE | ID: mdl-32875772

RESUMO

OBJECTIVE: To systematically evaluate the clinical efficacy of high-quality direct anterior approach (DAA) and other approaches for the treatment of elderly patients with femoral neck fracture. METHODS: Literatures published in English or Chinese about the direct anterior approach and other approaches for hemiarthroplasty in femoral neck fracture were searched on Cochrane Library, PubMed, EMBASE, Web of science, Wanfang, CNKI databases from their establishment to May 2019. According to the inclusion and exclusion criteria, two researchers independently screened the literatures, and extracted the data. The quality of RCT were evaluated by Cochrane Risk of Bias Assessment Tool, and non-RCT were evaluated by the NOS scale. Meta-analysis was performed using the RevMan 5.3 software. RESULTS: A total of 9 articles were included with 901 cases, in which 429 cases used DAA, and 472 used other approaches. DAA had a significantly lower dislocation rate compared to subgroup of posterior and posterolateral approach [OR=0.19, 95%CI (0.06, 0.61), P=0.005]. No significant differences were found between DAA group and subgroup of direct lateral and anterolateral approach[OR=1.08, 95%CI(0.20, 5.76), P=0.93]. Also there were no relevant differences between the DAA group and control in infection rate[OR=1.07, 95%CI(0.47, 2.43), P=0.88], perioperative fracture rate[OR=0.95, 95%CI(0.36, 2.50), P=0.92], re operation rate[OR=0.76, 95%CI(0.30, 1.89), P=0.55], overall complication rate [OR=0.88, 95%CI (0.63, 1.22), P=0.44], mortality [OR=1.33, 95%CI (0.84, 2.11), P=0.23], operative time[MD=1.43, 95%CI(-5.85, 8.71), P=0.70]. CONCLUSION: The current evidenceindicates that the DAA was associated with a significantly lower dislocation rate compared to posterior capsular approaches for hemiarthroplasty. There was no significant difference in dislocation rate with the lateral and anterolateral approach.


Assuntos
Antivirais , Artroplastia de Quadril , Fraturas do Colo Femoral/cirurgia , Hemiartroplastia , Hepatite C Crônica , Idoso , Humanos , Reoperação , Resultado do Tratamento
19.
Zhongguo Gu Shang ; 33(9): 797-801, 2020 Sep 25.
Artigo em Zh | MEDLINE | ID: mdl-32959565

RESUMO

OBJECTIVE: To investigate the feasibility of a drill template for the placement of guided template of middle and upper thoracic percutaneous vertebroplasty in thoracic pedicle approach on digital design and 3D printing technology. METHODS: The preoperative CT images of 20 patients with thoracic fracture were collected retrospectively. With the 3D soft tissue printing technology, the data was reconstructed by 3D imaging reconstruction software to produce 1∶1 three dimensional soft tissue model. The pedicle screw channel and the digital template were designed by the 3-matic module of Mimics15.0 software. After guide template was printed by 3D printer and three dimensional template was fixed on the model, 2.0 mm Kirschner was placed and the accuracy of a drill template was observed by CT scans, bone cement was injected through the puncture tube and verified with images. The time of nail guide design, guide template production and cost were recorded. RESULTS: The effectiveness of three dimensional thoracic model and digital guided template of middle and upper thoracic percutaneous vertebroplasty of thoracic fractures in thoracic pedicle approach was confirmed. Kirschner was placed and the accuracy of screw placement was confirmed with CT scanning. Template and the corresponding anatomical landmark fitted well, bone cement had showed good filling. The average printing time of upper thoracic spine model with soft tissue, the mean time of nail guide design, guide template production and cost were (719.00±3.03) min, (12.30±1.01) min, (55.50±10.30) min and RMB 3 150 yuan on average respectively. CONCLUSION: By means of individual design and 3D soft tissue printingtechnology, accurate placement of guided template of middle and upper thoracic percutaneous vertebroplasty could be realized.


Assuntos
Parafusos Pediculares , Cirurgia Assistida por Computador , Vertebroplastia , Humanos , Impressão Tridimensional , Estudos Retrospectivos
20.
Zhongguo Gu Shang ; 33(1): 47-52, 2020 Jan 25.
Artigo em Zh | MEDLINE | ID: mdl-32115924

RESUMO

OBJECTIVE: To compare the effect of percutaneous bridging plate and retrograde suprapubic intramedullary screw in the treatment of anterior ring fracture of pelvis. METHODS: From January 2013 to June 2017, 40 patients with unstable pelvic fractures involving anterior ring were analyzed retrospectively. According to the fixation method, they were divided into two groups, there were 20 patients in percutaneous bridging plate group (plate group) including 9 males and 11 females; according to tile classification, fractures were classified as type B1 in 1 case, type B2 in 14, type B3 in 2, type C1 in 2 and type C2 in 1. There were 20 cases in retrograde suprapubic intramedullary screw group (screw group) including 10 males and 10 females; according to tile classification, there were 1 case of type B1, 12 cases of type B2, 3 cases of type B3, 3 cases of type C1 and 1 case of type C2. The incision length, operation time, times of fluoroscopy, intraoperative bleeding volume, postoperative Matta score, postoperative complications and the last follow-up Majeed function score of the two groups were compared and analyzed. RESULTS: Both groups were followed up for 8 to 15 (12.25±2.24) months in the plate group and 6 to 18 (12.4±2.6) months in the screw group, there was no significant difference between the two groups. The incision length of screw group was (3.85±0.75) cm shorter than that of steel plate group (7.05±1.39) cm; the operation time of screw group was (27.70±5.36) min longer than that of steel plate group (15.10±2.07) min; the fluoroscopy times of screw group was (6.00±1.83) more than that of steel plate group (3.75±1.33) . The bleeding volume was (22.50±10.82) ml in of screw group, (25.00±9.93) ml in steel plate group, there was no significant difference between the two groups (P>0.05) . There was no significant difference in Matta evaluation and Majeed functional score in the last follow-up. One case of superficial skin infection occurred in screw group, one case of superficial skin infection and one case of transient paralysis of lateral femoral cutaneous nerve occurred in steel plate group. CONCLUSION: Percutaneous bridging plate and retrograde suprapubic intramedullary screw fixation of pelvic anterior ring fracture have the same effect. The operation time of the percutaneous plate group was shorter, the times of intraoperative fluoroscopy was less, and the learning curve was shorter, but the variation of the lateral femoral cutaneous nerve should be noted during the operation.


Assuntos
Fraturas Ósseas , Ossos Pélvicos , Placas Ósseas , Parafusos Ósseos , Feminino , Fixação Interna de Fraturas , Fraturas Ósseas/cirurgia , Humanos , Masculino , Estudos Retrospectivos , Resultado do Tratamento
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