RESUMEN
Management of scaphoid nonunion after failed surgery for acute scaphoid fracture presents a unique treatment challenge. Prior surgery complicates patient evaluation and increases the technical difficulty of future procedures. Healing of nonunion is crucial to prevent carpal collapse and progressive arthritis. A thorough workup is required to identify technical factors or treatment decisions that may have resulted in a poor outcome after initial fixation attempts. CT is particularly useful for characterizing nonunion and planning revision surgery. Several studies have described the use of bone grafts and fixation devices for scaphoid nonunion repair, including nonvascularized and vascularized bone grafts, screws, pins, and plates. Reliable rates of union have been achieved using nonvascularized bone graft supplemented with screw or wire fixation, particularly in the absence of osteonecrosis. Although vascularized grafts are more technically challenging, they improve the odds of union in the setting of osteonecrosis.
Asunto(s)
Trasplante Óseo/métodos , Fijación Interna de Fracturas/métodos , Fracturas no Consolidadas/etiología , Fracturas no Consolidadas/cirugía , Hueso Escafoides/lesiones , Traumatismos de la Muñeca/cirugía , Humanos , Reoperación , Hueso Escafoides/cirugíaRESUMEN
Plastic deformation of the forearm is a rare injury in young adults that occurs when a slow bending or rotational force is applied to the arm, most commonly in the setting of an industrial workplace accident. There are currently no guidelines for treatment of the residual forearm deformity that often results in limitations of forearm supination and pronation. We present 2 cases demonstrating that deformity correction with single cortex, double-level osteotomies combined with rigid plate fixation and early range of motion exercise that results in good functional outcomes.
Asunto(s)
Traumatismos del Brazo/cirugía , Desviación Ósea/cirugía , Fijación Interna de Fracturas/métodos , Osteotomía/métodos , Fracturas del Radio/cirugía , Fracturas del Cúbito/cirugía , Adolescente , Adulto , Traumatismos del Brazo/diagnóstico por imagen , Desviación Ósea/diagnóstico por imagen , Desviación Ósea/etiología , Placas Óseas , Femenino , Estudios de Seguimiento , Fijación Interna de Fracturas/efectos adversos , Fijación Interna de Fracturas/instrumentación , Humanos , Masculino , Cuidados Posoperatorios/métodos , Complicaciones Posoperatorias/diagnóstico por imagen , Complicaciones Posoperatorias/cirugía , Radiografía , Fracturas del Radio/diagnóstico por imagen , Recuperación de la Función , Reoperación , Medición de Riesgo , Factores de Tiempo , Resultado del Tratamiento , Fracturas del Cúbito/diagnóstico por imagen , Adulto JovenRESUMEN
PURPOSE: Avascular necrosis (AVN) is one of the most serious complications of femoral neck fractures in children. Variability in the reported rates of AVN and lack of statistical evidence has minimized the prognostic power of individual studies. The purpose of our study was to review our own cases as well as those from the literature in an effort to identify the risk factors for AVN. METHODS: We conducted a computerized search of medical records to identify all children with femoral neck fractures treated at our institution from 1980 to 2003. Records were reviewed to determine fracture type (Delbet type I to IV), displacement, age, treatment, and incidence of AVN. A structured search of PubMed was also performed to identify all reports published in English, on femoral neck fractures in children, from 1965 to 2003. Hand searches of major orthopedic journals and reference lists of publications identified additional cases. Of the 275 citations initially identified through our computerized search, 47 met the criteria for further evaluation. These citations were reviewed by 2 investigators, and data was abstracted from 20 reports that provided patient-level data and met our criteria for inclusion. RESULTS: Twenty-four patients with 25 femoral neck fractures from our institution were identified including 12 boys and 12 girls with an average age of 8 years (range 1.5 to 16). Over 300 patients who met our study criteria were also identified from the literature, and a total of 360 patients were included in the analysis. Fracture type, displacement, age, and treatment were all statistically significant independent predictors of AVN with P values Asunto(s)
Fracturas del Cuello Femoral/complicaciones
, Necrosis de la Cabeza Femoral/epidemiología
, Necrosis de la Cabeza Femoral/etiología
, Niño
, Preescolar
, Femenino
, Humanos
, Lactante
, Masculino
, Factores de Riesgo
RESUMEN
The process of vascular smooth muscle cell (vSMC) differentiation is critical to embryonic angiogenesis. However, despite its importance, the vSMC differentiation program remains largely undefined. Murine gene disruption studies have identified several gene products that are necessary for vSMC differentiation, but these methodologies cannot establish whether or not a factor is sufficient to initiate the differentiation program. A gain-of-function system consisting of normal vSMC progenitor cells would serve as a useful complement to whole animal loss-of-function studies. We use such a system here, namely freshly isolated rat neural crest stem cells (NCSCs), to show that activation of the calcineurin signaling pathway is sufficient to drive these cells toward a smooth muscle fate. In addition, we present data suggesting that transforming growth factor (TGF)-beta1, which also causes NCSCs to differentiate into smooth muscle, activates calcineurin signaling in NCSCs, leading to a model in which activation of calcineurin signaling is the mechanism by which TGF-beta1 causes SMC differentiation in these cells.