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1.
N Engl J Med ; 381(23): 2199-2208, 2019 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-31557429

RESUMO

BACKGROUND: Globally, hip fractures are among the top 10 causes of disability in adults. For displaced femoral neck fractures, there remains uncertainty regarding the effect of a total hip arthroplasty as compared with hemiarthroplasty. METHODS: We randomly assigned 1495 patients who were 50 years of age or older and had a displaced femoral neck fracture to undergo either total hip arthroplasty or hemiarthroplasty. All enrolled patients had been able to ambulate without the assistance of another person before the fracture occurred. The trial was conducted in 80 centers in 10 countries. The primary end point was a secondary hip procedure within 24 months of follow-up. Secondary end points included death, serious adverse events, hip-related complications, health-related quality of life, function, and overall health end points. RESULTS: The primary end point occurred in 57 of 718 patients (7.9%) who were randomly assigned to total hip arthroplasty and 60 of 723 patients (8.3%) who were randomly assigned to hemiarthroplasty (hazard ratio, 0.95; 95% confidence interval [CI], 0.64 to 1.40; P = 0.79). Hip instability or dislocation occurred in 34 patients (4.7%) assigned to total hip arthroplasty and 17 patients (2.4%) assigned to hemiarthroplasty (hazard ratio, 2.00; 99% CI, 0.97 to 4.09). Function, as measured with the total Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) total score, pain score, stiffness score, and function score, modestly favored total hip arthroplasty over hemiarthroplasty. Mortality was similar in the two treatment groups (14.3% among the patients assigned to total hip arthroplasty and 13.1% among those assigned to hemiarthroplasty, P = 0.48). Serious adverse events occurred in 300 patients (41.8%) assigned to total hip arthroplasty and in 265 patients (36.7%) assigned to hemiarthroplasty. CONCLUSIONS: Among independently ambulating patients with displaced femoral neck fractures, the incidence of secondary procedures did not differ significantly between patients who were randomly assigned to undergo total hip arthroplasty and those who were assigned to undergo hemiarthroplasty, and total hip arthroplasty provided a clinically unimportant improvement over hemiarthroplasty in function and quality of life over 24 months. (Funded by the Canadian Institutes of Health Research and others; ClinicalTrials.gov number, NCT00556842.).


Assuntos
Artroplastia de Quadril , Fraturas do Colo Femoral/cirurgia , Hemiartroplastia , Idoso , Idoso de 80 Anos ou mais , Artroplastia de Quadril/efeitos adversos , Feminino , Fraturas do Colo Femoral/fisiopatologia , Seguimentos , Hemiartroplastia/efeitos adversos , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Modelos de Riscos Proporcionais , Qualidade de Vida , Recuperação de Função Fisiológica , Reoperação/estatística & dados numéricos , Método Simples-Cego
2.
Aging Clin Exp Res ; 28(1): 1-16, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26746234

RESUMO

PURPOSE: This consensus review article considers the question of whether glucocorticoid (GC) therapy is still relevant in the treatment of rheumatic diseases, with a particular focus on rheumatoid arthritis (RA), and whether its side effects can be adequately managed. Recent basic and clinical research on the molecular, cellular and clinical effects of GCs have considerably advanced our knowledge in this field. An overview of the subject seems appropriate. METHODS: This review is the result of a multidisciplinary expert working group, organised by European Society for Clinical and Economic Aspects of Osteoporosis and Osteoarthritis. The recent literature was surveyed and the salient evidence synthetized. RESULTS: The pathophysiological basis of RA (and other inflammatory rheumatic diseases) now strongly implicates the adaptive immune system in addition to innate mechanisms. The molecular effect of GCs and differential GC sensitivity is better understood, although exploiting this knowledge is still in its infancy. The newer treatment strategies of early and aggressive control of RA have gr eatly improved clinical outcomes, but improvements are still possible. Newer targeted anti-inflammatory drugs have made an important impact, yet they too are associated with numerous side effects. DISCUSSION: Short durations of moderate doses of GCs are generally well tolerated and have a positive benefit/risk ratio. Patients should be assessed for fracture risk and bone preserving agents and be prescribed calcium and vitamin D supplementation. CONCLUSIONS: Within a strategy of a disease modifying approach to inflammatory disease, combination therapy including a GC is effective approach.


Assuntos
Glucocorticoides , Doenças Reumáticas/tratamento farmacológico , Anti-Inflamatórios/efeitos adversos , Anti-Inflamatórios/uso terapêutico , Consenso , Europa (Continente) , Glucocorticoides/efeitos adversos , Glucocorticoides/uso terapêutico , Humanos , Osteoporose/etiologia , Osteoporose/prevenção & controle , Medição de Risco
3.
Diabetologia ; 58(3): 633-642, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25563724

RESUMO

AIMS/HYPOTHESIS: Diabetes interferes with bone formation and impairs fracture healing, an important complication in humans and animal models. The aim of this study was to examine the impact of diabetes on mesenchymal stem cells (MSCs) during fracture repair. METHODS: Fracture of the long bones was induced in a streptozotocin-induced type 1 diabetic mouse model with or without insulin or a specific TNFα inhibitor, pegsunercept. MSCs were detected with cluster designation-271 (also known as p75 neurotrophin receptor) or stem cell antigen-1 (Sca-1) antibodies in areas of new endochondral bone formation in the calluses. MSC apoptosis was measured by TUNEL assay and proliferation was measured by Ki67 antibody. In vitro apoptosis and proliferation were examined in C3H10T1/2 and human-bone-marrow-derived MSCs following transfection with FOXO1 small interfering (si)RNA. RESULTS: Diabetes significantly increased TNFα levels and reduced MSC numbers in new bone area. MSC numbers were restored to normal levels with insulin or pegsunercept treatment. Inhibition of TNFα significantly reduced MSC loss by increasing MSC proliferation and decreasing MSC apoptosis in diabetic animals, but had no effect on MSCs in normoglycaemic animals. In vitro experiments established that TNFα alone was sufficient to induce apoptosis and inhibit proliferation of MSCs. Furthermore, silencing forkhead box protein O1 (FOXO1) prevented TNFα-induced MSC apoptosis and reduced proliferation by regulating apoptotic and cell cycle genes. CONCLUSIONS/INTERPRETATION: Diabetes-enhanced TNFα significantly reduced MSC numbers in new bone areas during fracture healing. Mechanistically, diabetes-enhanced TNFα reduced MSC proliferation and increased MSC apoptosis. Reducing the activity of TNFα in vivo may help to preserve endogenous MSCs and maximise regenerative potential in diabetic patients.


Assuntos
Diabetes Mellitus/metabolismo , Consolidação da Fratura/fisiologia , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Adapaleno/metabolismo , Animais , Antígenos Ly/metabolismo , Apoptose/fisiologia , Linhagem Celular , Células Cultivadas , Diabetes Mellitus/fisiopatologia , Diabetes Mellitus Experimental , Humanos , Proteínas de Membrana/metabolismo , Camundongos , Osteogênese/fisiologia
4.
J Cell Physiol ; 228(11): 2232-42, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23625810

RESUMO

Runx2 and Runx3 are known to be expressed in the growth plate during endochondral bone formation. Here we addressed the functional role of Runx3 as distinct from Runx2 by using two models of postnatal bone repair: fracture healing that proceeds by an endochondral process and marrow ablation that proceeds by only an intramembranous process. Both Runx2 and Runx3 mRNAs were differentially up regulated during fracture healing. In contrast, only Runx2 showed increased expression after marrow ablation. During fracture healing, Runx3 was expressed earlier than Runx2, was concurrent with the period of chondrogenesis, and coincident with maximal aggrecan expression a protein associated with proliferating and permanent cartilage. Immunohistological analysis showed Runx3 protein was also expressed by chondrocytes in vivo. In contrast, Runx2 was expressed later during chondrocyte hypertrophy, and primary bone formation. The functional activities of Runx3 during chondrocyte differentiation were assessed by examining its regulatory actions on aggrecan gene expression. Aggrecan mRNA levels and aggrecan promoter activity were enhanced in response to the over-expression of either Runx2 and Runx3 in ATDC5 chondrogenic cell line, while sh-RNA knocked down of each Runx protein showed that only Runx3 knock down specifically suppressed aggrecan mRNA expression and promoter activity. ChIP assay demonstrated that Runx3 interactions were selective to sites within the aggrecan promoter and were only observed during early periods of chondrogenesis before hypertrophy. Our studies suggest that Runx3 positively regulates aggrecan expression and suggest that its function is more limited to cartilage development than to bone. In aggregate these data further suggest that the various members of the Runx transcription factors are involved in the coordination of chondrocyte development, maturation, and hypertrophy during endochondral bone formation.


Assuntos
Agrecanas/genética , Cartilagem/crescimento & desenvolvimento , Cartilagem/metabolismo , Condrogênese/genética , Subunidade alfa 3 de Fator de Ligação ao Core/metabolismo , Regulação da Expressão Gênica , Agrecanas/metabolismo , Animais , Sequência de Bases , Diferenciação Celular/genética , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Subunidade alfa 3 de Fator de Ligação ao Core/genética , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Especificidade de Órgãos/genética , Osteogênese/genética , Regiões Promotoras Genéticas/genética , Ligação Proteica/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fatores de Tempo
5.
Orthop Clin North Am ; 54(1): 1-6, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36402505

RESUMO

MyArthritisRx.com (MARx) is an online digital platform with resources to effectively manage osteoarthritis and directs patients to the appropriate information and tools to manage their disease. The key to self-management is a self-evaluation and staging program powered by an algorithm based on 150,000 arthritis patients. Outcome data (PROMs), comorbidities, demographics, and personalized characteristics are used to provide a personalized self-evaluation and staging assessment which characterizes disease severity and risk of progression. The initial 6-week program was completed by 100 pilot patients with 92% reporting some improvement. MARx offers evidence of efficacy with promise of cost savings and improved arthritis care.


Assuntos
Osteoartrite do Joelho , Autogestão , Humanos , Osteoartrite do Joelho/terapia , Índice de Gravidade de Doença
6.
Biochem Biophys Res Commun ; 417(1): 211-6, 2012 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-22142851

RESUMO

Post natal bone repair elicits a regenerative mechanism that restores the injured tissue to its pre-injury cellular composition and structure and is believed to recapitulate the embryological processes of bone formation. Prior studies showed that Nanog, a central epigenetic regulator associated with the maintenance of embryonic stem cells (ESC) was transiently expressed during fracture healing, Bais et al. In this study, we show that murine bone marrow stromal cells (MSCs) before they are induced to undergo osteogenic differentiation express ∼50× the background levels of Nanog seen in murine embryonic fibroblasts (MEFs) and the W20-17 murine marrow stromal cell line stably expresses Nanog at ∼80× the MEF levels. Nanog expression in this cell line was inhibited by BMP7 treatment and Nanog lentivrial shRNA knockdown induced the expression of the terminal osteogenic gene osteocalcin. Lentivrial shRNA knockdown or lentiviral overexpression of Nanog in bone MSCs had inverse effects on proliferation, with knockdown decreasing and overexpression increasing MSC cell proliferation. Surgical marrow ablation of mouse tibia by medullary reaming led to a ∼3-fold increase in Nanog that preceded osteogenic differentiation during intramembranous bone formation. Lentiviral shRNA knockdown of Nanog after surgical ablation led to an initial overexpression of osteogenic gene expression with no initial effect on bone formation but during subsequent remodeling of the newly formed bone a ∼50% decrease was seen in the expression of terminal osteogenic gene expression and a ∼50% loss in trabecular bone mass. This loss of bone mass was accompanied by an increased ∼2- to 5-fold adipogenic gene expression and observed increase of fat cells in the marrow space. In summary these data show that Nanog is expressed during surgically induced marrow bone formation and is functionally involved in post natal marrow stromal cell maintenance and differentiation.


Assuntos
Células da Medula Óssea/fisiologia , Regeneração Óssea , Proteínas de Homeodomínio/fisiologia , Osteogênese , Células-Tronco/fisiologia , Adipogenia , Animais , Células da Medula Óssea/metabolismo , Proliferação de Células , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteína Homeobox Nanog , Células-Tronco/metabolismo , Células Estromais/metabolismo , Células Estromais/fisiologia
7.
J Arthroplasty ; 27(4): 569-74, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21855279

RESUMO

The aim of this study was to determine the degree of variability in implants, approaches, and associated complication rates in randomized controlled trials (RCTs) evaluating primary total hip arthroplasty (THA) as an intervention for displaced femoral neck fractures. We searched 2 medical databases for RCTs involving THA for femoral neck fractures published between June 2000 and June 2010. All analyses were descriptive. Nine RCTs met our inclusion criteria. We identified variability in both the surgical approach and choice of prosthesis. Trials generally standardized to head sizes of 28 mm or greater and cemented prostheses. Surgical experience varied across studies. Dislocation rates varied from 0% to 22%. There is considerable variability in RCTs evaluating THA for femoral neck fractures. Standardization toward optimal outcomes for femoral neck fractures is needed.


Assuntos
Artroplastia de Quadril/métodos , Fraturas do Colo Femoral/cirurgia , Prótese de Quadril/classificação , Idoso , Idoso de 80 Anos ou mais , Artroplastia de Quadril/efeitos adversos , Artroplastia de Quadril/mortalidade , Feminino , Luxação do Quadril/epidemiologia , Articulação do Quadril/cirurgia , Humanos , Masculino , Prevalência , Ensaios Clínicos Controlados Aleatórios como Assunto , Taxa de Sobrevida
8.
Arthritis Rheum ; 62(4): 1108-18, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20131271

RESUMO

OBJECTIVE: To characterize patterns of molecular expression that lead to cartilage formation in vivo in a postnatal setting, by profiling messenger RNA expression across the time course of mechanically induced chondrogenesis. METHODS: Retired breeder Sprague-Dawley rats underwent a noncritical-sized transverse femoral osteotomy. Experimental animals (n = 45) were subjected to bending stimulation (60 degrees cyclic motion in the sagittal plane for 15 minutes/day) of the osteotomy gap beginning on day 10 after the operation. Control animals (n = 32) experienced continuous rigid fixation. Messenger RNA isolated on days 10, 17, 24, and 38 after surgery was analyzed using a microarray containing 608 genes involved in skeletal development, tissue differentiation, fracture healing, and mechanotransduction. The glycosaminoglycan (GAG) content in the stimulated tissues was compared with that in native articular cartilage as a means of assessing the progression of chondrogenic development of the tissues. RESULTS: The majority of the 100 genes that were differentially expressed were up-regulated in response to mechanical stimulation. Many of these genes are associated with articular cartilage development and maintenance, diarthrodial joint development, cell adhesion, extracellular matrix synthesis, signal transduction, and skeletal development. Quantitative real-time polymerase chain reaction results were consistent with the microarray findings. The GAG content of the stimulated tissues increased over time and was no different from that of articular cartilage on day 38 after surgery. CONCLUSION: Our findings indicate that mechanical stimulation causes up-regulation of genes that are principally involved in joint cavity morphogenesis and critical to articular cartilage function. Further study of this type of stimulation may identify key signaling events required for postnatal hyaline cartilage formation.


Assuntos
Cartilagem Articular/fisiologia , Perfilação da Expressão Gênica , Transcrição Gênica , Animais , Cartilagem Articular/metabolismo , Condrogênese/genética , Condrogênese/fisiologia , Fêmur/cirurgia , Regulação da Expressão Gênica , Masculino , Modelos Animais , Família Multigênica/genética , Análise de Sequência com Séries de Oligonucleotídeos , Osteotomia , Postura , RNA Mensageiro/genética , RNA Mensageiro/isolamento & purificação , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa
9.
Clin Orthop Relat Res ; 469(8): 2215-24, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21132409

RESUMO

BACKGROUND: The definition of bone quality is evolving particularly from the perspective of anabolic agents that can enhance not only bone mineral density but also bone microarchitecture, composition, morphology, amount of microdamage, and remodeling dynamics. QUESTIONS/PURPOSES: This review summarizes the molecular pathways and physiologic effects of current and potential anabolic drugs. METHODS: From a MEDLINE search (1996-2010), articles were identified by the search terms "bone quality" (1851 articles), "anabolic agent" (5044 articles), "PTH or parathyroid hormone" (32,229 articles), "strontium" or "strontium ranelate" (283 articles), "prostaglandin" (77,539 articles), and "statin" or "statins" (14,233 articles). The search strategy included combining each with the phrase "bone quality." Another more limited search aimed at finding more novel potential agents. RESULTS: Parathyroid hormone is the only US Food and Drug Administration-approved bone anabolic agent in the United States and has been the most extensively studied in in vitro animal and human trials. Strontium ranelate is approved in Europe but has not undergone Food and Drug Administration trials in the United States. All the studies on prostaglandin agonists have used in vivo animal models and there are no human trials examining prostaglandin agonist effects. The advantages of statins include the long-established advantages and safety profile, but they are limited by their bioavailability in bone. Other potential pathways include proline-rich tyrosine kinase 2 (PYK2) and sclerostin (SOST) inhibition, among others. CONCLUSIONS: The ongoing research to enhance the anabolic potential of current agents, identify new agents, and develop better delivery systems will greatly enhance the management of bone quality-related injuries and diseases in the future.


Assuntos
Anabolizantes/farmacologia , Remodelação Óssea/fisiologia , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/fisiologia , Proteínas Adaptadoras de Transdução de Sinal , Anabolizantes/uso terapêutico , Animais , Conservadores da Densidade Óssea/administração & dosagem , Conservadores da Densidade Óssea/farmacologia , Proteínas Morfogenéticas Ósseas/fisiologia , Remodelação Óssea/efeitos dos fármacos , Quinase 2 de Adesão Focal/fisiologia , Consolidação da Fratura/efeitos dos fármacos , Marcadores Genéticos/fisiologia , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Fator de Crescimento Insulin-Like I/uso terapêutico , Compostos Organometálicos/farmacologia , Osteoporose/tratamento farmacológico , Hormônio Paratireóideo/fisiologia , Fragmentos de Peptídeos/administração & dosagem , Prostaglandinas/agonistas , Teriparatida/administração & dosagem , Teriparatida/análogos & derivados , Tiofenos/farmacologia
10.
Proc Natl Acad Sci U S A ; 105(2): 686-91, 2008 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-18184809

RESUMO

The hypoxia-inducible factor-1alpha (HIF-1alpha) pathway is the central regulator of adaptive responses to low oxygen availability and is required for normal skeletal development. Here, we demonstrate that the HIF-1alpha pathway is activated during bone repair and can be manipulated genetically and pharmacologically to improve skeletal healing. Mice lacking pVHL in osteoblasts with constitutive HIF-1alpha activation in osteoblasts had markedly increased vascularity and produced more bone in response to distraction osteogenesis, whereas mice lacking HIF-1alpha in osteoblasts had impaired angiogenesis and bone healing. The increased vascularity and bone regeneration in the pVHL mutants were VEGF dependent and eliminated by concomitant administration of VEGF receptor antibodies. Small-molecule inhibitors of HIF prolyl hydroxylation stabilized HIF/VEGF production and increased angiogenesis in vitro. One of these molecules (DFO) administered in vivo into the distraction gap increased angiogenesis and markedly improved bone regeneration. These results identify the HIF-1alpha pathway as a critical mediator of neoangiogenesis required for skeletal regeneration and suggest the application of HIF activators as therapies to improve bone healing.


Assuntos
Regeneração Óssea/fisiologia , Regulação da Expressão Gênica , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Osteoblastos/metabolismo , Animais , Fenômenos Biomecânicos , Linhagem Celular Tumoral , Endotélio Vascular/metabolismo , Humanos , Camundongos , Modelos Biológicos , Neovascularização Patológica , Osteogênese , Receptores de Fatores de Crescimento do Endotélio Vascular/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Proteína Supressora de Tumor Von Hippel-Lindau/metabolismo
11.
Ann N Y Acad Sci ; 1490(1): 77-89, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33543485

RESUMO

Type 2 diabetes mellitus (T2DM) significantly increases bone fragility and fracture risk. Progranulin (PGRN) promotes bone fracture healing in both physiological and type 1 diabetic conditions. The present study aimed to investigate the role of PGRN in T2DM bone fracture healing. MKR mice (with an FVB/N genetic background) were used as the T2DM model. Drill-hole and Bonnarens and Einhorn models were used to investigate the role of PGRN in T2DM fracture healing in vivo. Primary bone marrow cells were isolated for molecular and signaling studies, and reverse transcription-polymerase chain reaction, immunohistochemical staining, and western blotting were performed to assess PGRN effects in vitro. PGRN mRNA and protein expression were upregulated in the T2DM model. Local administration of recombinant PGRN effectively promoted T2DM bone fracture healing in vivo. Additionally, PGRN could induce anabolic metabolism during endochondral ossification through the TNFR2-Akt and Erk1/2 pathways. Furthermore, PGRN showed anti-inflammatory activity in the T2DM bone regeneration process. These findings suggest that local administration of exogenous PGRN may be an alternative strategy to support bone regeneration in patients with T2DM. Additionally, PGRN might hold therapeutic potential for other TNFR-related metabolic disorders.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Diabetes Mellitus Tipo 2/patologia , Consolidação da Fratura/efeitos dos fármacos , Fraturas Ósseas/tratamento farmacológico , Osteogênese/efeitos dos fármacos , Progranulinas/uso terapêutico , Anabolizantes/uso terapêutico , Animais , Humanos , Camundongos , Camundongos Transgênicos , Receptores Tipo II do Fator de Necrose Tumoral/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
12.
Am J Pathol ; 175(4): 1574-85, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19745063

RESUMO

Diabetes interferes with fracture repair; therefore, we investigated mechanisms of impaired fracture healing in a model of multiple low-dose streptozotocin-induced diabetes. Microarray and gene set enrichment analysis revealed an up-regulation of gene sets related to inflammation, including tumor necrosis factor (TNF) signaling in the diabetic group, when cartilage is being replaced by bone on day 16, but not on days 12 or 22. This change coincided with elevated osteoclast numbers and accelerated removal of cartilage in the diabetic group (P < 0.05), which was reflected by smaller callus size. When diabetic mice were treated with the TNF-specific inhibitor, pegsunercept, the number of osteoclasts, cartilage loss, and number of TNF-alpha and receptor activator for nuclear factor kB ligand positive chondrocytes were significantly reduced (P < 0.05). The transcription factor forkhead box 01 (FOXO1) was tested for mediating TNF stimulation of osteoclastogenic and inflammatory factors in bone morphogenetic protein 2 pretreated ATDC5 and C3H10T1/2 chondrogenic cells. FOXO1 knockdown by small-interfering RNA significantly reduced TNF-alpha, receptor activator for nuclear factor kB ligand, macrophage colony-stimulating factor, interleukin-1alpha, and interleukin-6 mRNA compared with scrambled small-interfering RNA. An association between FOXO1 and the TNF-alpha promoter was demonstrated by chromatin immunoprecipitation assay. Moreover, diabetes increased FOXO1 nuclear translocation in chondrocytes in vivo and increased FOXO1 DNA binding activity in diabetic fracture calluses (P < 0.05). These results suggest that diabetes-enhanced TNF-alpha increases the expression of resorptive factors in chondrocytes through a process that involves activation of FOXO1 and that TNF-alpha dysregulation leads to enhanced osteoclast formation and accelerated loss of cartilage.


Assuntos
Cartilagem/metabolismo , Cartilagem/patologia , Diabetes Mellitus/metabolismo , Diabetes Mellitus/patologia , Consolidação da Fratura , Fator de Necrose Tumoral alfa/metabolismo , Animais , Núcleo Celular/metabolismo , Condrócitos/metabolismo , Condrócitos/patologia , DNA/metabolismo , Proteína Forkhead Box O1 , Fatores de Transcrição Forkhead , Técnicas de Silenciamento de Genes , Inflamação/metabolismo , Inflamação/patologia , Mediadores da Inflamação/metabolismo , Masculino , Camundongos , Osteoclastos/metabolismo , Osteoclastos/patologia , Osteogênese , Fenótipo , Ligação Proteica , Ligante RANK/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fator de Necrose Tumoral alfa/genética , Regulação para Cima/genética
13.
Instr Course Lect ; 59: 607-17, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20415409

RESUMO

It is important for orthopaedic surgeons to understand the role of prostaglandins in bone physiology and the mechanism of action of nonsteroidal anti-inflammatory drugs and their role in fracture healing, fusion, osteointegration, and aseptic loosening. Nonsteroidal anti-inflammatory drugs have benefits and risks in orthopaedic use, and their effects should be considered.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Osso e Ossos/efeitos dos fármacos , Consolidação da Fratura/efeitos dos fármacos , Osseointegração/efeitos dos fármacos , Tendões/efeitos dos fármacos , Fixação de Fratura , Humanos , Falha de Prótese , Fusão Vertebral
14.
Clin Cases Miner Bone Metab ; 7(1): 11-4, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22461283

RESUMO

Anti-fracture agents typically prevent fractures by augmenting bone mass and enhancing skeletal integrity. These agents exert their effects by means of anti-catabolic or anabolic actions. Because fracture healing involves bone formation as well as bone resorption, it is reasonable to hypothesize that agents that affect these activities may also modulate skeletal repair. Bisphosphonates, agents that inhibit bone resorption, may enhance the healing of fractures or permit patients with fractures to bear weight earlier by delaying the conversion of calcified cartilage to woven bone, or woven bone to lamellar bone. In doing so, they increase the size of the fracture callus and small increases in the radius of fracture callus can have dramatic positive effects on fracture callus stiffness and strength. Another possibility is that certain hypertrophic nonunions fail to unite because of excessive remodeling of the callus. Use of a bisphosphonate may modulate this catabolic activity, uncouple it from the associated bone formation and promote healing. Inhibitors of RANKL have undergone far less investigation but may also act on osteoclast precursors to down-regulate bone resorption. Parathyroid hormone may enhance fracture repair by promoting chondrogenesis early in the healing process and osteogenesis at a later time. The former effect improves callus geometry while the latter effect improves bone quality as well as quantity. Several anecdotal reports and one randomized, controlled trial have suggested that parathyroid may enhance skeletal repair in specific clinical settings.Although these reports are based on solid scientific data, there are limited clinical data at this time. The use of anti-fracture agents for the enhancement of fracture healing will ultimately depend upon high quality evidence from well-designed, well-controlled clinical trials.

15.
J Biomech ; 112: 110039, 2020 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-32980751

RESUMO

Implant alignment and soft-tissue balancing are important factors in total knee arthroplasty (TKA). The purpose of this study was to design a mechanical balancing device, which measures deflections resulting from forces applied on each condyle to provide numerical data indicating the extent of ligament release needed, or angular changes in the bone cuts required to achieve a balanced knee. Two mechanical devices were designed and 3D printed, Pistol Grip and In-line. The Pistol Grip design consisted of a lever system that indicated the difference between lateral and medial forces with a single pointer. The In-line design allows for the quantification of the absolute force applied on each individual condyle. The two designs were evaluated on a test rig designed to model balance and imbalance conditions in the knee. For the Pistol Grip design maximum pointer deflection indicates a 2 mm change in elevation per condyle and/or a 3 degrees angular change of the condyles which can be corrected by adjusting the ligament lengths equivalent to 2 mm and/or by modifying the proximal or distal femur bone cut by 3 degrees. For the In-line design, maximum pointer deflection represented a 40 N load on the condyle. Our mechanical balancer designs were successful in providing information that can guide surgeons to accurately achieve balance through ligamentous releases and/or modification to bone cuts. The balancer designs are easy to use, do not require any electronics or software, and can be incorporated into the surgical procedure.


Assuntos
Artroplastia do Joelho , Prótese do Joelho , Fêmur/cirurgia , Humanos , Joelho/cirurgia , Articulação do Joelho/cirurgia , Impressão Tridimensional , Amplitude de Movimento Articular
16.
Ann N Y Acad Sci ; 1460(1): 43-56, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31423598

RESUMO

Type 1 diabetes mellitus (T1DM) is an autoimmune disease characterized by insulin deficiency, and patients with diabetes have an increased risk of bone fracture and significantly impaired fracture healing. Proinflammatory cytokine tumor necrosis factor-alpha is significantly upregulated in diabetic fractures and is believed to underlie delayed fracture healing commonly observed in diabetes. Our previous genetic screen for the binding partners of progranulin (PGRN), a growth factor-like molecule that induces chondrogenesis, led to the identification of tumor necrosis factor receptors (TNFRs) as the PGRN-binding receptors. In this study, we employed several in vivo models to ascertain whether PGRN has therapeutic effects in diabetic fracture healing. Here, we report that deletion of PGRN significantly delayed bone fracture healing and aggravated inflammation in the fracture models of mice with T1DM. In contrast, recombinant PGRN effectively promoted diabetic fracture healing by inhibiting inflammation and enhancing chondrogenesis. In addition, both TNFR1 proinflammatory and TNFR2 anti-inflammatory signaling pathways are involved in PGRN-stimulated diabetic fracture healing. Collectively, these findings illuminate a novel understanding concerning the role of PGRN in diabetic fracture healing and may have an application in the development of novel therapeutic intervention strategies for diabetic and other types of impaired fracture healing.


Assuntos
Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Tipo 1/patologia , Consolidação da Fratura/efeitos dos fármacos , Progranulinas/farmacologia , Animais , Condrogênese/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Deleção de Genes , Humanos , Inflamação/patologia , Camundongos , Progranulinas/deficiência , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores do Fator de Necrose Tumoral/metabolismo , Proteínas Recombinantes/farmacologia , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
17.
Clin Orthop Relat Res ; 467(2): 558-65, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19030943

RESUMO

Stress, emotional exhaustion, and burnout are widespread in the medical profession in general and in orthopaedic surgery in particular. We attempted to identify variables associated with burnout as assessed by validated instruments. Surveys were sent to 282 leaders from orthopaedic surgery academic departments in the United States by e-mail and mail. Responses were received from 195 leaders for a response rate of 69%. The average surgeon worked 68.3 hours per week and more than (1/2) of this time was allocated to patient care. Highest stressors included excessive workload, increasing overhead, departmental budget deficits, tenure and promotion, disputes with the dean, and loss of key faculty. Personal-professional life imbalance was identified as an important risk factor for emotional exhaustion. Withdrawal, irritability, and family disagreements are early warning indicators of burnout and emotional exhaustion. Orthopaedic leaders can learn, and potentially model, ways to mitigate stress from other high-stress professions. Building on the strength of marital and family bonds, improving stress management skills and self-regulation, and improving efficiency and productivity can combine to assist the orthopaedic surgery leader in preventing burnout and emotional exhaustion.


Assuntos
Esgotamento Profissional/diagnóstico , Esgotamento Profissional/prevenção & controle , Ortopedia , Médicos/psicologia , Eficiência Organizacional , Humanos , Relações Interpessoais , Ortopedia/organização & administração , Satisfação Pessoal , Inquéritos e Questionários
18.
J Clin Med ; 9(1)2019 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-31878248

RESUMO

Fracture haematoma forms immediately after fracture and is considered essential for the bone healing process. Its molecular composition has been briefly investigated with our current understanding being based on animal studies. This study aims to analyse the inflammatory cytokine content of fracture haematoma in humans and determine its effect on osteoprogenitor cells. Twenty-three patients were recruited following informed consent. Peripheral blood, fracture haematoma and bone were collected. A Luminex assay on the levels of 34 cytokines was performed and autologous peripheral blood samples served as control. Mesenchymal Stem Cells (MSCs) were isolated following collagenase digestion and functional assays were performed. Gene expression analysis of 84 key osteogenic molecules was performed. Thirty-three inflammatory cytokines were found to be significantly raised in fracture haematoma when compared to peripheral serum (p < 0.05). Amongst the most raised molecules were IL-8, IL-11 and MMP1, -2 and -3. Fracture haematoma did not significantly affect MSC proliferation, but ALP activity and calcium deposition were significantly increased in the MSCs undergoing osteogenic differentiation. Medium supplementations with fracture haematoma resulted in a statistically significant upregulation of osteogenic genes including the EGF, FGF2 and VEGFA. This seems to be the pathway involved in the osteogenic effect of fracture haematoma on bone cells. In conclusion, fracture haematoma is found to be a medium rich in inflammatory and immunomodulatory mediators. At the same time, it contains high levels of anti-inflammatory molecules, regulates osteoclastogenesis, induces angiogenesis and the production of the extracellular matrix. It appears that fracture haematoma does not affect osteoprogenitor cells proliferation as previously thought, but induces an osteogenic phenotype.

19.
JBJS Rev ; 7(8): e5, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31415278

RESUMO

BACKGROUND: The minimum clinically important difference (MCID) was developed to ascertain the smallest change in an outcome that patients perceive as beneficial. The objectives of the present review were (1) to compare the MCIDs for pain assessments used among guidelines and meta-analyses investigating different nonsurgical therapies for knee osteoarthritis and (2) to compare the effect estimates of different nonsurgical interventions against a single commonly-utilized MCID threshold. METHODS: Systematic and manual searches were conducted to identify guidelines and meta-analyses evaluating pain outcomes for nonsurgical knee osteoarthritis interventions. Individual treatment effects for pain were presented on a common scale (the standardized mean difference [SMD]). To evaluate the perception of the relative benefit of each nonsurgical treatment, the variation in MCIDs selected from the published MCID literature was assessed. RESULTS: Thirty-seven guidelines and meta-analyses were included. MCIDs were often presented as an SMD or a mean difference (MD) on a validated scale and varied in magnitude across sources. This analysis demonstrated that intra-articular hyaluronic acid, intra-articular corticosteroids, and acetaminophen all had relatively larger effect sizes than topical nonsteroidal anti-inflammatory drugs (NSAIDs). Higher-molecular-weight intra-articular hyaluronic acid had a greater relative effect compared with both non-selective and cyclooxygenase-2-selective oral NSAIDs. Evaluating the treatment effect estimates against a commonly utilized MCID revealed similarities in which observations attained clinical significance among treatments; however, this observation varied across the range of reported MCIDs. CONCLUSIONS: The present review confirmed the variability in the MCIDs for pain assessments that are used across guidelines and meta-analyses evaluating nonsurgical interventions for knee osteoarthritis. This variability may yield conflicting treatment recommendations, ranging from rejecting treatments that are indeed efficacious to accepting treatments that may not be beneficial. Additional research is required to determine why some nonsurgical therapies are more consistently recommended in knee osteoarthritis guidelines than others as these findings suggest similarities in their effect estimates for pain. Relevant stakeholders need to reach a consensus on a standard approach to determining the MCIDs for these therapies to ensure that appropriate and effective treatment options are available to patients prior to invasive surgical intervention. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.


Assuntos
Diferença Mínima Clinicamente Importante , Osteoartrite do Joelho/terapia , Corticosteroides/administração & dosagem , Corticosteroides/uso terapêutico , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/uso terapêutico , Artralgia/tratamento farmacológico , Artralgia/etiologia , Artralgia/fisiopatologia , Humanos , Ácido Hialurônico/administração & dosagem , Ácido Hialurônico/uso terapêutico , Injeções Intra-Articulares , Osteoartrite do Joelho/complicações , Guias de Prática Clínica como Assunto
20.
J Orthop Trauma ; 22(2): 126-30; discussion 130-1, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18349781

RESUMO

OBJECTIVES: External fixation devices are sold in the United States as single-use devices and can be costly. Approved processes for refurbishment of nonimplantable components are available. We evaluated one such program for safety, efficacy, and fiscal ramifications. DESIGN: Randomized clinical trial SETTING: Single center, Level I trauma center PATIENTS/PARTICIPANTS: During the 30-month enrollment period (November 16, 2001 to May 16, 2004), 41 patients (13%) of 315 patients were not able to consent and were excluded. A total of 178 (65%) of the 274 eligible patients who were offered entry into a randomized trial of new versus refurbished external fixation components for their injury refused to participate, leaving 96 (35%) of the 274 eligible patients entered into the study. INTERVENTION: Consented patients were entered into a trial of new versus refurbished nonimplantable external fixation components for their injury (all pins were new). MAIN OUTCOME MEASUREMENTS: The frames were evaluated at the time of removal for efficacy and the complications of pin tract infections, loss of fixation, or loosening of components. RESULTS: A total of 48 distal radius fractures, 29 pilon fractures, and 19 tibial plateau fractures were entered into the study. With the 96 fractures treated in our study (50 new frames, 46 reused frames), we found no statistical differences in the incidence of pin tract infections (46% versus 52%, P=0.32), loss of fixation (4% versus 4%, P=0.70), or loosening of the components (1% versus 1%, P=1.0). CONCLUSIONS: Sixty-five percent of consentable patients did not wish to have an external fixation frame with refurbished clamps. Our study demonstrated that this type of program is safe and effective with an actual cost savings of $65,452. The potential savings of such a program is 25% of the cost of all new frames.


Assuntos
Fixadores Externos , Fraturas do Rádio/cirurgia , Fraturas da Tíbia/cirurgia , Adulto , Idoso , Redução de Custos , Reutilização de Equipamento/economia , Fixadores Externos/economia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
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