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1.
Eur J Orthop Surg Traumatol ; 34(3): 1675-1681, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38403660

RESUMO

PURPOSE: To determine outcomes following surgical management of terrible triad injuries in patients treated with and without a hinged elbow orthosis (HEO) in the post-operative setting. METHODS: This study was a retrospective review of 41 patients who underwent surgical treatment of terrible triad injuries including radial head fracture, coronoid fracture, and ulnohumeral dislocation between 2008 and 2023 with at least 10-week follow-up. RESULTS: Nineteen patients were treated post-operatively without HEO, and 22 patients were treated with HEO. There were no differences in range of motion (ROM) between patients treated with and without HEO in final flexion-extension arc (118.4° no HEO, 114.6° HEO, p = 0.59) or pronation-supination arc (147.8° no HEO, 141.4° HEO, p = 0.27). Five patients treated without HEO and one patient treated with HEO returned to the operating room for stiffness (26%, 5%, p = 0.08). QuickDASH scores were similar between groups (p = 0.69). CONCLUSIONS: This study found no difference in post-operative ROM, complications, or QuickDASH scores in patients treated post-operatively with or without HEO. Based on these results, we cannot determine whether the use of HEO adds additional stability to the elbow while initiating ROM exercises post-operatively.


Assuntos
Lesões no Cotovelo , Articulação do Cotovelo , Luxações Articulares , Instabilidade Articular , Fraturas do Rádio , Humanos , Cotovelo , Instabilidade Articular/etiologia , Resultado do Tratamento , Articulação do Cotovelo/cirurgia , Luxações Articulares/etiologia , Luxações Articulares/cirurgia , Fraturas do Rádio/cirurgia , Fraturas do Rádio/etiologia , Aparelhos Ortopédicos , Amplitude de Movimento Articular , Estudos Retrospectivos , Fixação Interna de Fraturas/efeitos adversos
2.
Curr Osteoporos Rep ; 20(5): 320-325, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36129609

RESUMO

PURPOSE OF REVIEW: This review summarizes recent investigations into the cellular and molecular effects of skeletal aging on the inflammatory response and stem cell function after fracture. RECENT FINDINGS: Proper regulation of the inflammatory phase of fracture healing is essential. Aging is associated with chronic inflammation, which inhibits bone formation and promotes bone resorption. Osteogenic differentiation and anti-senescence pathways in skeletal stem cells are impaired in geriatric fractures. As the population ages, fragility fractures will continue to represent a significant clinical problem, which will require innovative clinical solutions. Skeletal stem cells in geriatric individuals demonstrate defects in anti-senescence pathways that lead to impaired osteogenic differentiation in vitro in humans. Small molecule-based therapies can partially reverse the aging phenotype. In the future, molecular- or cell-based therapies modulating either inflammatory cells or skeletal stem cells represent potential therapeutic targets to augment contemporary fracture healing interventions in osteoporotic or aging individuals.


Assuntos
Fraturas Ósseas , Osteogênese , Idoso , Envelhecimento/metabolismo , Consolidação da Fratura/fisiologia , Humanos , Inflamação/metabolismo , Células-Tronco/fisiologia
3.
Arch Orthop Trauma Surg ; 142(10): 2533-2544, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33829301

RESUMO

INTRODUCTION: Achieving durable mechanical stability in geriatric intertrochanteric proximal femur fractures remains a challenge. Concomitant poor bone quality, unstable fracture patterns, and suboptimal reduction are additional risk factors for early mechanical failure. Cement augmentation of the proximal locking screw or blade is one proposed method to augment implant anchorage. The purpose of this review is to describe the biomechanical and clinical evidence for cement augmentation of geriatric intertrochanteric fractures, and to elaborate indications for cement augmentation. METHODS: The PubMed database was searched for English language studies up to January 2021. Studies that assessed effect of calcium phosphate or methylmethacrylate cement augmentation during open reduction and internal fixation of intertrochanteric fractures were included. Studies with sample size < 5, nontraumatic or periprosthetic fractures, and nonunion or revision surgery were excluded. Study selection adhered to PRISMA criteria. RESULTS: 801 studies were identified, of which 40 met study criteria. 9 studies assessed effect of cement augmentation on fracture displacement. All but one found that cement decreased fracture displacement. 10 studies assessed effect of cement augmentation on total load or cycles to failure. All but one demonstrated that augmented implants increased this variable. Complication rates of cement augmentation during ORIF of intertrochanteric fractures ranged from 0 to 47%, while non-augmented implants ranged from 0 to 51%. Reoperation rates ranged from 0 to 11% in the cement-augmented group and 0 to 11% in the non-augmented group. Fixation failure ranged from 0 to 11% in the cement-augmented group and 0 to 20% in the non-augmented group. Nonunion ranged from 0 to 3.6% in the cement-augmented group and 0 to 34% in the non-augmented group. CONCLUSIONS: Calcium phosphate or PMMA-augmented CMN fixation of IT fractures increased construct stability and improved outcomes in biomechanical and early clinical studies. The findings of these studies suggest an important role for cement augmentation in patient populations at high risk of mechanical failure.


Assuntos
Cimentos Ósseos , Fraturas do Quadril , Idoso , Fenômenos Biomecânicos , Parafusos Ósseos , Fosfatos de Cálcio/uso terapêutico , Fêmur , Fixação Interna de Fraturas/métodos , Fraturas do Quadril/cirurgia , Humanos
4.
Arch Orthop Trauma Surg ; 142(7): 1367-1374, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33484311

RESUMO

OBJECTIVES: The purpose of the study was to compare treatment outcomes after short or long cephalomedullary nailing for intertrochanteric femur fractures. DATA SOURCES: A systematic review of perioperative outcomes after short or long cephalomedullary nailing for intertrochanteric femur fractures was performed. The following databases were used: using the Cochrane Database of Systematic Reviews, the Cochrane Central Register of Controlled Trials, PubMed (1980-2019), and MEDLINE (1980-2019). The queries were performed in June 2019. STUDY SELECTION: The following search term query was used: "Intramedullary Nail AND Intertrochanteric Fracture OR "Long OR Short Nail AND intertrochanteric Fracture." Studies were excluded if they were "single-arm" studies (i.e., reporting on either long or short CMN but not both), or did not report at least one of the outcomes being meta-analyzed. Furthermore, cadaveric studies, animal studies, basic science articles, editorial articles, surveys and studies were excluded. DATA EXTRACTION: Two investigators independently reviewed abstracts from all identified articles. Full-text articles were obtained for review if necessary, to allow further assessment of inclusion and exclusion criteria. Additionally, all references from the included studies were reviewed and reconciled to verify that no relevant articles were missing from the systematic review. DATA SYNTHESIS: Short nails were associated with statistically significantly less estimated blood loss and operative time compared to long nails. There were no significant differences in transfusion rates, implant failures or overall re-operation rates between implant lengths. Similarly, there was no significant difference in peri-implant fracture between implant lengths. CONCLUSIONS: Overall, the available clinical evidence supports the use of short cephalomedullary nails for the majority of intertrochanteric femur fractures. STUDY DESIGN/LEVEL OF EVIDENCE: Meta-analysis; Level III, therapeutic.


Assuntos
Fixação Intramedular de Fraturas , Fraturas do Quadril , Fraturas Periprotéticas , Pinos Ortopédicos , Fraturas do Quadril/cirurgia , Humanos , Estudos Retrospectivos , Revisões Sistemáticas como Assunto , Resultado do Tratamento
5.
Instr Course Lect ; 70: 563-576, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33438936

RESUMO

The practicing orthopaedic surgeon must understand the relationship between fracture biomechanics and fracture biology to optimize patient outcomes. Patient characteristics, fracture pattern, and desired type of bone healing all drive decision making. The benefits of performing an open approach to a fracture, obtaining an anatomic reduction, and achieving absolute stability must be weighed against the biologic cost to the tissues and the potential to compromise healing. Similarly, the decision to perform a closed fracture reduction; apply a splint, bridge plate, or intramedullary nail; and achieve relative stability requires that the surgeon understand the implications of increased strain at a given fracture site. The purpose of this chapter is to review the basic science of primary and secondary bone healing with special attention given to the clinical implications for practicing surgeons.


Assuntos
Fixação Intramedular de Fraturas , Ortopedia , Biofísica , Pinos Ortopédicos , Consolidação da Fratura , Humanos
6.
Eur J Orthop Surg Traumatol ; 31(1): 65-70, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32710126

RESUMO

PURPOSE: The optimal management of valgus-impacted femoral neck fractures remains controversial. Internal fixation is associated with significant rates of re-operation, while historical non-operative management strategies consisting of prolonged bed rest also resulted in patient morbidity. Our hypothesis was that screw fixation would have comparable failure rates to non-operative treatment and immediate mobilization for valgus-impacted femoral neck fractures. METHODS: Retrospective cohort at a single academic Level I trauma center of patients with valgus-impacted femoral neck fractures (AO/OTA 31-B1) treated with percutaneous screw fixation (n = 97) or non-operatively (n = 28). Operative treatment consisted of percutaneous screw fixation. Non-operative treatment consisted of early mobilization. The primary outcome was a salvage operation. Patient demographics were assessed between groups. RESULTS: More non-operatively treated patients were permitted unrestricted weight-bearing (WBAT; p = 0.002). There was no increase in complication rates or mortality, and return to previous ambulatory status was comparable between operatively and non-operatively treated patients. 35.7% (10/28) of non-operatively treated patients underwent a subsequent operation, compared to 15.5% (15/97) of patients with screw fixation (p = 0.03). Only WBAT was independently associated with treatment failure (OR 3.1, 95%CI 1.2-8.3, p =0.02). WBAT was predictive of treatment failure only in the non-operatively treated group (64.3%, 9/14 WBAT vs 8.3%, 1/12 partial, p =0.005). CONCLUSION: After controlling for weight-bearing restrictions, we found no difference in failure rates between non-operative treatment and screw fixation. Non-operative treatment with partial weight-bearing had low failure rates, comparable complication and mortality rates, and equivalent functional outcomes to operative treatment and is reasonable if a patient would like to avoid surgery and accepts the risk of subsequent arthroplasty. Overall, there were relatively high failure rates in all groups.


Assuntos
Tratamento Conservador , Fraturas do Colo Femoral , Fixação Interna de Fraturas , Adulto , Idoso , Idoso de 80 Anos ou mais , Parafusos Ósseos , Feminino , Fraturas do Colo Femoral/cirurgia , Fraturas do Colo Femoral/terapia , Fixação Interna de Fraturas/efeitos adversos , Fixação Interna de Fraturas/instrumentação , Fixação Interna de Fraturas/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Reoperação , Estudos Retrospectivos , Resultado do Tratamento , Suporte de Carga
7.
Eur J Orthop Surg Traumatol ; 31(2): 259-264, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32804288

RESUMO

Intra-articular screw cut-out is a potential complication of intertrochanteric femur fracture fixation with a cephalomedullary nail. Cement augmentation of fixation in the proximal segment offers the prospect of increased stability and fewer complications, but clinical experience with non-resorbable cement is limited. To determine the handling properties and efficacy of this new technique, we performed a retrospective propensity-matched cohort of forty-four geriatric intertrochanteric femur fractures treated with a cephalomedullary nail with (n = 11) or without (n = 33) augmentation with non-resorbable cement injected into the proximal segment. In the patients treated with cement augmentation, at minimum 3-month follow-up, there were no instances of intra-articular cut-out, and no increase in re-operation compared to conventional fixation. Cement augmentation appears to be safe and effective in geriatric intertrochanteric femur fractures to mitigate risk of cut-out.


Assuntos
Fixação Intramedular de Fraturas , Fraturas do Quadril , Idoso , Cimentos Ósseos/uso terapêutico , Pinos Ortopédicos , Fêmur/diagnóstico por imagem , Fêmur/cirurgia , Fraturas do Quadril/diagnóstico por imagem , Fraturas do Quadril/cirurgia , Humanos , Estudos Retrospectivos
8.
Eur J Orthop Surg Traumatol ; 31(7): 1421-1425, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33587180

RESUMO

OBJECTIVES: Excessive fracture site collapse and shortening in intertrochanteric femur fractures alter hip biomechanics and patient outcomes. The purpose of the study was to compare extent of collapse in cephalomedullary nails with blades or lag screws. We hypothesized that there would be no difference in collapse between helical blades and lag screws. DESIGN: Retrospective cohort study. SETTING: Single U.S. Level I Trauma Center. PATIENTS: 171 consecutive patients treated with cephalomedullary nails with either lag screw or blade for AO/OTA 31A1-3 proximal femur fractures and minimum 3-month follow-up. INTERVENTION: Lag screw or helical blade in a cephalomedullary nail. OUTCOME MEASURES: The primary outcome was fracture site collapse at 3 months. RESULTS: There was a significantly higher proportion of reverse-oblique and transverse intertrochanteric femur fractures (31-A3) in the lag screw group (15/42 vs 25/129). A3 patterns were associated with more collapse. There was significantly less collapse in the blade group (median 4.7 mm, inter-quartile range 2.5-7.8 mm) than the screw group (median 8.4 mmm, inter-quartile range 3.7-11.2 mm, p 0.006). Median collapse was no different between blades and screws when comparing stable and unstable patterns. However, blades were independently associated with 2.5 mm less collapse (95%CI - 4.2, - 0.72 mm, p 0.006) and lower likelihood of excessive collapse (> 10 mm at 3 months, OR 0.3, 95% CI 0.13-0.74, p 0.007), regardless of fracture pattern. CONCLUSIONS: Helical blades are independently associated with significantly less collapse than lag screws in intertrochanteric proximal femur fractures, after adjusting for unstable fracture patterns. In fracture patterns at risk for collapse, surgeons can consider use of a helical blade due to its favorable sliding properties compared to screws.


Assuntos
Fixação Intramedular de Fraturas , Fraturas do Quadril , Pinos Ortopédicos , Parafusos Ósseos , Fêmur , Fixação Intramedular de Fraturas/efeitos adversos , Fraturas do Quadril/diagnóstico por imagem , Fraturas do Quadril/cirurgia , Humanos , Estudos Retrospectivos , Resultado do Tratamento
9.
Eur J Orthop Surg Traumatol ; 31(3): 421-427, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32909108

RESUMO

BACKGROUND: Cephalomedullary nails are a commonly used implant for the treatment of many pertrochanteric femur fractures and are available in short and long configurations. There is no consensus on ideal nail length. Relative advantages can be ascribed to short and long intramedullary nails, yet both implant styles share the potentially devastating complication of peri-implant fracture. Determining the clinical sequelae after fractures below nails of different lengths would provide valuable information for surgeons choosing between short or long nails. Thus, the purpose of the study was to compare injury patterns and treatment outcomes following peri-implant fractures below short or long cephalomedullary nails. METHODS: This was a multicenter retrospective cohort study that identified 33 patients referred for treatment of peri-implant fractures below short and long cephalomedullary nails (n = 19 short, n = 14 long). We compared fracture pattern, treatment strategy, complications, and outcomes between these two groups. RESULTS: Short nails were associated with more diaphyseal fractures (odds ratio [OR] 13.75, CI 2.2-57.9, p 0.002), which were treated more commonly with revision intramedullary nailing (OR, infinity; p 0.01), while long nails were associated with distal metaphyseal fractures (OR 13.75, CI 2.2-57.9, p 0.002), which were treated with plate and screw fixation (p 0.002). After peri-implant fracture, there were no differences in blood loss, operative time, weight bearing status, or complication rates based on the length of the initial nail. In patients treated with revision nailing, there was greater estimated blood loss (EBL, median 300 cc, interquartile range [IQR] 250-1200 vs median 200 cc, IQR 100-300, p 0.03), blood product utilization and complication rates (OR 11.1, CI 1.1-135.7, p 0.03), but a trend toward unrestricted post-operative weight-bearing compared to patients treated with plate and screw constructs. CONCLUSION: Understanding fracture patterns and patient outcomes after fractures below nails of different lengths will help surgeons make more informed implant choices when treating intertrochanteric hip fractures. Revision to a long nail for the treatment of fractures at the tip of a short nail may be associated with increased patient morbidity.


Assuntos
Fixação Intramedular de Fraturas , Fraturas do Quadril , Fraturas Periprotéticas , Pinos Ortopédicos , Fixação Intramedular de Fraturas/efeitos adversos , Fraturas do Quadril/etiologia , Fraturas do Quadril/cirurgia , Humanos , Fraturas Periprotéticas/etiologia , Fraturas Periprotéticas/cirurgia , Estudos Retrospectivos
10.
PLoS Genet ; 10(2): e1004152, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24586192

RESUMO

The cranial bones and dermis differentiate from mesenchyme beneath the surface ectoderm. Fate selection in cranial mesenchyme requires the canonical Wnt effector molecule ß-catenin, but the relative contribution of Wnt ligand sources in this process remains unknown. Here we show Wnt ligands are expressed in cranial surface ectoderm and underlying supraorbital mesenchyme during dermal and osteoblast fate selection. Using conditional genetics, we eliminate secretion of all Wnt ligands from cranial surface ectoderm or undifferentiated mesenchyme, to uncover distinct roles for ectoderm- and mesenchyme-derived Wnts. Ectoderm Wnt ligands induce osteoblast and dermal fibroblast progenitor specification while initiating expression of a subset of mesenchymal Wnts. Mesenchyme Wnt ligands are subsequently essential during differentiation of dermal and osteoblast progenitors. Finally, ectoderm-derived Wnt ligands provide an inductive cue to the cranial mesenchyme for the fate selection of dermal fibroblast and osteoblast lineages. Thus two sources of Wnt ligands perform distinct functions during osteoblast and dermal fibroblast formation.


Assuntos
Diferenciação Celular/genética , Crânio/crescimento & desenvolvimento , Proteínas Wnt/metabolismo , beta Catenina/metabolismo , Animais , Ectoderma/crescimento & desenvolvimento , Ectoderma/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Ligantes , Mesoderma/citologia , Mesoderma/crescimento & desenvolvimento , Camundongos , Osteoblastos/citologia , Osteoblastos/metabolismo , Transdução de Sinais , Crânio/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismo
11.
Dev Dyn ; 245(2): 144-56, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26677825

RESUMO

BACKGROUND: Specification of cranial bone and dermal fibroblast progenitors in the supraorbital arch mesenchyme is Wnt/ß-catenin signaling-dependent. The mechanism underlying how these cells interpret instructive signaling cues and differentiate into these two lineages is unclear. Twist1 is a target of the Wnt/ß-catenin signaling pathway and is expressed in cranial bone and dermal lineages. RESULTS: Here, we show that onset of Twist1 expression in the mouse cranial mesenchyme is dependent on ectodermal Wnts and mesenchymal ß-catenin activity. Conditional deletion of Twist1 in the supraorbital arch mesenchyme leads to cranial bone agenesis and hypoplastic dermis, as well as craniofacial malformation of eyes and palate. Twist1 is preferentially required for cranial bone lineage commitment by maintaining Wnt responsiveness. In the conditional absence of Twist1, the cranial dermis fails to condense and expand apically leading to extensive cranial dermal hypoplasia with few and undifferentiated hair follicles. CONCLUSIONS: Thus, Twist1, a target of canonical Wnt/ß-catenin signaling, also functions to maintain Wnt responsiveness and is a key effector for cranial bone fate selection and dermal condensation.


Assuntos
Anormalidades Craniofaciais/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Proteínas Nucleares/metabolismo , Crânio/embriologia , Proteína 1 Relacionada a Twist/metabolismo , Via de Sinalização Wnt/fisiologia , Animais , Anormalidades Craniofaciais/genética , Folículo Piloso/metabolismo , Camundongos , Camundongos Knockout , Proteínas Nucleares/genética , Crânio/metabolismo , Proteína 1 Relacionada a Twist/genética , Proteínas Wnt/metabolismo , beta Catenina/metabolismo
12.
J Neurosci ; 35(17): 6836-48, 2015 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-25926459

RESUMO

The ERK/MAPK pathway is an important developmental signaling pathway. Mutations in upstream elements of this pathway result in neuro-cardio-facial cutaneous (NCFC) syndromes, which are typified by impaired neurocognitive abilities that are reliant upon hippocampal function. The role of ERK signaling during hippocampal development has not been examined and may provide critical insight into the cause of hippocampal dysfunction in NCFC syndromes. In this study, we have generated ERK1 and conditional ERK2 compound knock-out mice to determine the role of ERK signaling during development of the hippocampal dentate gyrus. We found that loss of both ERK1 and ERK2 resulted in 60% fewer granule cells and near complete absence of neural progenitor pools in the postnatal dentate gyrus. Loss of ERK1/2 impaired maintenance of neural progenitors as they migrate from the dentate ventricular zone to the dentate gyrus proper, resulting in premature depletion of neural progenitor cells beginning at E16.5, which prevented generation of granule cells later in development. Finally, loss of ERK2 alone does not impair development of the dentate gyrus as animals expressing only ERK1 developed a normal hippocampus. These findings establish that ERK signaling regulates maintenance of progenitor cells required for development of the dentate gyrus.


Assuntos
Giro Denteado , Retroalimentação Fisiológica/fisiologia , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Sistema de Sinalização das MAP Quinases/fisiologia , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Células-Tronco/fisiologia , Animais , Animais Recém-Nascidos , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Giro Denteado/embriologia , Giro Denteado/enzimologia , Giro Denteado/crescimento & desenvolvimento , Embrião de Mamíferos , Feminino , Regulação da Expressão Gênica no Desenvolvimento/genética , Ventrículos Laterais/citologia , Ventrículos Laterais/embriologia , Ventrículos Laterais/crescimento & desenvolvimento , Sistema de Sinalização das MAP Quinases/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Neurogênese/genética , Neurônios/metabolismo , Proteínas Proto-Oncogênicas c-raf/genética , Proteínas Proto-Oncogênicas c-raf/metabolismo
13.
Development ; 139(23): 4428-38, 2012 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-23095887

RESUMO

The bones of the mammalian skull vault form through intramembranous ossification. Skull bones ossify directly, in a process regulated by ß-catenin, instead of passing through a cartilage intermediate. We tested whether ß-catenin is necessary for fate selection of intramembranous bone progenitors in the skull. Here, we show in mice that removal of ß-catenin from skull bone progenitors results in the near complete transformation of the skull bones to cartilage, whereas constitutive ß-catenin activation inhibits skull bone fate selection. ß-catenin directly activated Twist1 expression in skull progenitors, conditional Twist1 deletion partially phenocopied the absence of ß-catenin, and Twist1 deletion partially restored bone formation in the presence of constitutive ß-catenin activation. Finally, Twist1 bound robustly to the 3'UTR of Sox9, the central initiator of chondrogenesis, suggesting that Twist1 might directly repress cartilage formation through Sox9. These findings provide insight into how ß-catenin signaling via Twist1 actively suppresses the formation of cartilage and promotes intramembranous ossification in the skull.


Assuntos
Condrogênese , Proteínas Nucleares/metabolismo , Crânio/citologia , Crânio/embriologia , Células-Tronco/fisiologia , Proteína 1 Relacionada a Twist/metabolismo , beta Catenina/metabolismo , Animais , Desenvolvimento Ósseo , Cartilagem/citologia , Diferenciação Celular , Linhagem Celular , Linhagem da Célula , Camundongos , Camundongos Endogâmicos C3H , Camundongos Transgênicos , Proteínas Nucleares/genética , Osteoblastos/metabolismo , Osteogênese , Regiões Promotoras Genéticas , Fatores de Transcrição SOX9/metabolismo , Transdução de Sinais , Proteína 1 Relacionada a Twist/genética
14.
Neuroimage ; 102 Pt 2: 809-16, 2014 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-25213753

RESUMO

Dystrophin, the main component of the dystrophin-glycoprotein complex, plays an important role in maintaining the structural integrity of cells. It is also involved in the formation of the blood-brain barrier (BBB). To elucidate the impact of dystrophin disruption in vivo, we characterized changes in cerebral perfusion and diffusion in dystrophin-deficient mice (mdx) by magnetic resonance imaging (MRI). Arterial spin labeling (ASL) and diffusion-weighted MRI (DWI) studies were performed on 2-month-old and 10-month-old mdx mice and their age-matched wild-type controls (WT). The imaging results were correlated with Evan's blue extravasation and vascular density studies. The results show that dystrophin disruption significantly decreased the mean cerebral diffusivity in both 2-month-old (7.38 ± 0.30 × 10(-4)mm(2)/s) and 10-month-old (6.93 ± 0.53 × 10(-4)mm(2)/s) mdx mice as compared to WT (8.49 ± 0.24 × 10(-4), 8.24 ± 0.25 × 10(-4)mm(2)/s, respectively). There was also an 18% decrease in cerebral perfusion in 10-month-old mdx mice as compared to WT, which was associated with enhanced arteriogenesis. The reduction in water diffusivity in mdx mice is likely due to an increase in cerebral edema or the existence of large molecules in the extracellular space from a leaky BBB. The observation of decreased perfusion in the setting of enhanced arteriogenesis may be caused by an increase of intracranial pressure from cerebral edema. This study demonstrates the defects in water handling at the BBB and consequently, abnormal perfusion associated with the absence of dystrophin.


Assuntos
Barreira Hematoencefálica/fisiopatologia , Circulação Cerebrovascular/fisiologia , Distrofina/deficiência , Animais , Imageamento por Ressonância Magnética , Masculino , Camundongos , Camundongos Endogâmicos C57BL
15.
Injury ; 55(8): 111662, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38897069

RESUMO

PURPOSE: To identify a cohort of isolated medial tibial plateau fractures treated with surgical fixation and to categorize them by Moore and Wahlquist classifications in order to determine the rate of complications with each fracture morphology and the predictive value of each classification system. We hypothesized there would be high rates of neurovascular injury, compartment syndrome, and complications overall with a higher incidence of neurovascular injury in Moore type III rim avulsion fractures and Wahlquist type C fractures that enter the plateau lateral to the tibial spines. METHODS: Patients who presented to six Level I trauma centers between 2010 and 2021 who underwent surgical fixation for isolated medial tibial plateau fractures were retrospectively reviewed. Data including demographics, radiographs, complications, and functional outcomes were collected. RESULTS: One hundred and fifty isolated medial tibial plateau fractures were included. All patients were classified by the Wahlquist classification of medial tibial plateau fractures, and 139 patients were classifiable by the Moore classification of tibial plateau fracture-dislocations. Nine percent of fractures presented with neurovascular injury: 5 % with isolated vascular injury and 6 % with isolated nerve injury. There were no significant differences in neurovascular injury by fracture type (Wahlquist p = 0.16, Moore p = 0.33). Compartment syndrome developed in two patients (1.3 %). The average final range of motion was 0.8-122° with no difference by Wahlquist or Moore classifications (p = 0.11, p = 0.52). The overall complication rate was 32 % without differences by fracture morphology. The overall rate of return to the operating room (OR) was 25 %. CONCLUSIONS: Isolated medial tibial plateau fractures often represent fracture-dislocations of the knee and should receive a meticulous neurovascular exam on presentation with a high suspicion for neurovascular injury. No specific fracture pattern was found to be predictive of neurovascular injuries, complications, or final knee range of motion. Patients should be counseled pre-operatively regarding high rates of return to the OR after the index surgery.

16.
J Orthop Trauma ; 38(2): 57-64, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38031262

RESUMO

OBJECTIVES: To compare clinical and radiographic outcomes after retrograde intramedullary nailing (rIMN) versus locked plating (LP) of "extreme distal" periprosthetic femur fractures, defined as those that contact or extend distal to the anterior flange. DESIGN: Retrospective review. SETTING: Eight academic level I trauma centers. PATIENT SELECTION CRITERIA: Adult patients with periprosthetic distal femur fractures at or distal to the anterior flange (OTA/AO 33B-C[VB1]) treated with rIMN or LP. OUTCOME MEASURES AND COMPARISONS: The primary outcome was reoperation to promote healing or to treat infection (reoperation for elective removal of symptomatic hardware was excluded from this analysis). Secondary outcomes included nonunion, delayed union, fixation failure, infection, overall reoperation rate, distal femoral alignment, and ambulatory status at final follow-up. Outcomes were compared between patients treated with rIMN or LP. RESULTS: Seventy-one patients treated with rIMN and 224 patients treated with LP were included. The rIMN group had fewer points of fixation in the distal segment (rIMN: 3.5 ± 1.1 vs. LP: 6.0 ± 1.1, P < 0.001) and more patients who were allowed to weight-bear as tolerated immediately postoperatively (rIMN: 45%; LP: 9%, P < 0.01). Reoperation to promote union and/or treat infection was 8% in the rIMN group and 16% in the LP group ( P = 0.122). There were no significant differences in nonunion ( P > 0.999), delayed union ( P = 0.079), fixation failure ( P > 0.999), infection ( P = 0.084), or overall reoperation rate ( P > 0.999). Significantly more patients in the rIMN group were ambulatory without assistive devices at final follow-up (rIMN: 35%, LP: 18%, P = 0.008). CONCLUSIONS: rIMN of extreme distal periprosthetic femur fractures has similar complication rates compared with LP, with a possible advantage of earlier return to weight-bearing. Surgeons can consider this treatment strategy in all fractures with stable implants and amenable prosthesis geometry, even extreme distal fractures. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.


Assuntos
Artroplastia do Joelho , Fraturas do Fêmur , Fixação Intramedular de Fraturas , Fraturas Periprotéticas , Adulto , Humanos , Fixação Intramedular de Fraturas/efeitos adversos , Estudos Retrospectivos , Fraturas do Fêmur/etiologia , Consolidação da Fratura , Placas Ósseas/efeitos adversos , Fixação Interna de Fraturas , Fêmur/cirurgia , Fraturas Periprotéticas/complicações , Artroplastia do Joelho/efeitos adversos , Resultado do Tratamento
17.
J Orthop Trauma ; 37(8): e335-e340, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-36730014

RESUMO

SUMMARY: Displaced tongue-type calcaneus fractures are frequently associated with severe soft tissue injuries, and urgent relief of the displaced tongue fragment on the posterior soft tissues is essential to preventing soft tissue complications. If there is a complex articular injury, the soft tissue envelope often needs time for swelling to resolve to allow for a safe open anatomic reduction because premature open reduction internal fixation is often associated with increased complications. We have found that in high-energy tongue-type calcaneus fractures with complex articular injuries, a staged protocol consisting of initial percutaneous reduction and fixation with later definitive reconstruction is soft tissue friendly, allows early restoration of calcaneal morphology, and affords extensile approaches for eventual reconstruction. The purpose of this study was to describe our protocol of staged treatment of high-energy tongue-type calcaneus fractures, along with postoperative surgical outcomes, in a case series of 53 patients.Our series of patients had a high rate of intra-articular injury with marked initial displacement (mean Bohler angle -8.4 ± 20.8 degrees). They were treated initially with percutaneous reduction and fixation at median 1 day postinjury (interquartile range [IQR] 0-1) and definitively at median 16 days postinjury (IQR 10-33). In this series, 2 of 53 (3.8%) patients developed a deep wound infection.In high-energy tongue-type calcaneus fractures at risk for soft tissue compromise or with a significantly displaced tongue fragment without initial soft tissue compromise, we found that staged management represents a feasible management strategy to mitigate risk of soft tissue complications and therefore helps facilitate safe definitive open treatment.


Assuntos
Traumatismos do Tornozelo , Calcâneo , Traumatismos do Pé , Fraturas Ósseas , Fraturas Intra-Articulares , Humanos , Calcâneo/diagnóstico por imagem , Calcâneo/cirurgia , Calcâneo/lesões , Fixação Interna de Fraturas/métodos , Resultado do Tratamento , Estudos Retrospectivos , Fraturas Ósseas/diagnóstico por imagem , Fraturas Ósseas/cirurgia , Fraturas Ósseas/etiologia , Traumatismos do Tornozelo/cirurgia , Fraturas Intra-Articulares/diagnóstico por imagem , Fraturas Intra-Articulares/cirurgia
18.
J Am Acad Orthop Surg ; 31(5): 252-257, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36729759

RESUMO

OBJECTIVE: The purpose of this study was to determine whether type III open high-energy tibia fractures treated with immediate intramedullary nailing (IMN) and primary closure yield low rates of flap coverage. METHODS: Patients with high-energy type IIIA open tibia (OTA/AO42/43) fractures treated with IMN over a 10-year period at a level 1 academic center with at least 90 days of in-person postoperative follow-up were included. Single-stage reamed IMN with acute primary skin closure using Allgower-Donati suture technique was utilized in patients without notable skin loss. The primary outcome was treatment failure of acute primary skin closure requiring subsequent soft-tissue coverage procedures. RESULTS: A total of 111 patients with type IIIA tibia fractures met inclusion criteria. Of 107 of the 111 patients (96%) with skin closure at the index surgery, 95 of the 107 patients (89%) healed their soft-tissue envelop uneventfully. Among the patients who failed primary closure (11%), five required free tissue transfers, five required local rotational flaps, and two underwent split thickness skin grafting only. Patients who failed acute primary closure declared within an average of 8 weeks postoperatively. DISCUSSION: Treatment of type IIIA open high-energy tibia fractures with immediate IMN and primary closure using meticulous soft-tissue handling yields low rates of flap coverage.


Assuntos
Fixação Intramedular de Fraturas , Fraturas Expostas , Fraturas da Tíbia , Humanos , Fixação Intramedular de Fraturas/métodos , Tíbia , Fraturas da Tíbia/cirurgia , Retalhos Cirúrgicos , Pele , Fraturas Expostas/cirurgia , Estudos Retrospectivos , Resultado do Tratamento , Consolidação da Fratura
19.
J Orthop Trauma ; 36(Suppl 3): S33-S34, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35838577

RESUMO

SUMMARY: Posteromedial talar body fractures are a rare form of talus fracture that involves the tibiotalar and subtalar joints. In cases of displaced injuries, open reduction and internal fixation is typically recommended to minimize the risk of instability and post-traumatic osteoarthritis. This video presents a case of a posteromedial talar body fracture and highlights the technique for operative fixation through a posteromedial approach. Multiple methods to obtain reduction are discussed, and considerations with implant placement are described. The indications for surgical intervention are reviewed, and published outcomes following operative and nonoperative management of these injuries are presented.


Assuntos
Fraturas Ósseas , Tálus , Articulação do Tornozelo/cirurgia , Fixação Interna de Fraturas/métodos , Fraturas Ósseas/diagnóstico por imagem , Fraturas Ósseas/cirurgia , Humanos , Redução Aberta , Tálus/diagnóstico por imagem , Tálus/lesões , Tálus/cirurgia
20.
J Orthop ; 30: 41-45, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35241886

RESUMO

INTRODUCTION: Though long-term functional outcomes of olecranon fracture plate fixation are favorable, postoperative implant irritation commonly leads to elective removal. We hypothesized that mini-fragment plates will decrease implant removal compared to precontoured plates. METHODS: Patients with isolated olecranon fracture (AO/OTA 2U1-B1) treated with plate fixation were retrospectively reviewed. Patients were stratified into groups based on whether they underwent open reduction and internal fixation with a (1) surgeon contoured mini-fragment or (2) precontoured olecranon-specific plate. Rates of symptomatic implants and implant removal were compared. RESULTS: 98 and 32 patients were treated with precontoured and mini-fragment plates, respectively. Baseline demographics and comorbidities were similar. Mean follow-up was 20.6 months. There were no differences in rates of postoperative complication (22/98, 22.4% vs. 5/32, 15.6%; p = 0.41) or reoperation (37/98, 37.8% vs. 8/32, 25%; p = 0.19). Symptomatic implants were common in the precontoured cohort (44/98, 44.9% vs. 7/32, 21.9%; p < 0.05). Implant removal rates were 36.7% and 18.8%, respectively (p = 0.06). DISCUSSION/CONCLUSION: Olecranon fracture stabilization with mini-fragment plate is associated with lower rates of symptomatic implants, with no difference in postoperative complications or reoperations. Mini-fragment plating is a safe and promising alternative to precontoured plating.

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