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1.
J Sci Educ Technol ; 32(3): 338-354, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37113266

RESUMEN

Drawing on transformative experience theory (Pugh, 2011) and in collaboration with high school science teachers, the authors developed an intervention (Seeing Science project) leveraging everyday mobile technology as a tool for integrating in-school and out-of-school experience. Students were instructed to take pictures when they noticed connections to unit content and post these with a caption on a class site. The current study used design-based research methods to revise and evaluate the Seeing Science project over a 2-year period. Revisions to the project were informed by year one data and principles of the Teaching for Transformative Experiences in Science (TTES) instructional model. Data sources included project artifacts, student interviews, and teacher interviews. Revisions to the project resulted in higher quality posts in pre-AP biology classes and greater participation in regular biology classes. Furthermore, an analysis of posts, classroom observations, and student interviews revealed that the project helped some students connect in-school learning to out-of-school experience and undergo transformative experiences. The current study contributes to transformative experience theory by identifying and developing strategies for fostering transformative experiences. These strategies further inform the TTES model and may support depth of learning and career identification.

2.
J Surg Orthop Adv ; 25(1): 8-12, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27082882

RESUMEN

Although biomechanical and clinical evidence exists regarding smaller compression screws, biomechanical data regarding the larger headless screws are not currently available. Headed and headless 6.5-mm cannulated compression screws were examined, with analysis of interfragmentary compression, insertion torque, and resistance of the construct to a shear force. No significant differences were seen between the maximum insertion torque of the headless or headed screws. Maximum and steady-state compression forces were also not significantly different between groups. Countersinking the headless model 2 mm led to a 77.01% decrease in steady-state compression levels. Shear testing did not reveal any significant differences in peak load at ultimate failure, specimen stiffness, or final block displacement, although a trend to increased peak load and stiffness was seen with the headless specimens.


Asunto(s)
Tornillos Óseos , Ensayo de Materiales , Fenómenos Biomecánicos , Diseño de Equipo , Fijación Interna de Fracturas/instrumentación , Humanos , Resistencia al Corte , Torque
3.
Orthopedics ; 35(6): 518-27, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22691643

RESUMEN

Limb deformity can occur in the pediatric and adolescent populations from multiple etiologies: congenital, traumatic, posttraumatic sequelae, oncologic, and infection. Correcting these deformities is important for many reasons. Ilizarov popularized external fixation to accomplish this task. Taylor expanded on this by designing an external fixator in 1994 with 6 telescoping struts that can be sequentially manipulated to achieve multiaxial correction of deformity without the need for hinges or operative frame alterations. This frame can be used to correct deformities in children and has shown good anatomic correction with minimal morbidity. The nature of the construct and length of treatment affects psychosocial factors that the surgeon and family must be aware of prior to treatment. An understanding of applications of the Taylor Spatial Frame gives orthopedic surgeons an extra tool to correct simple and complex deformities in pediatric and adolescent patients.


Asunto(s)
Técnica de Ilizarov/instrumentación , Diferencia de Longitud de las Piernas/cirugía , Adolescente , Niño , Preescolar , Análisis de Falla de Equipo , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Diseño de Prótesis , Resultado del Tratamiento
4.
Orthopedics ; 34(8): e349-55, 2011 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-21815575

RESUMEN

Fracture fixation of the medial malleolus in rotationally unstable ankle fractures typically results in healing with current fixation methods. However, when failure occurs, pullout of the screws from tension, compression, and rotational forces is predictable. We sought to biomechanically test a relatively new technique of bicortical screw fixation for medial malleoli fractures. Also, the AO group recommends tension-band fixation of small avulsion type fractures of the medial malleolus that are unacceptable for screw fixation. A well-documented complication of this technique is prominent symptomatic implants and secondary surgery for implant removal. Replacing stainless steel 18-gauge wire with FiberWire suture could theoretically decrease symptomatic implants. Therefore, a second goal was to biomechanically compare these 2 tension-band constructs. Using a tibial Sawbones model, 2 bicortical screws were compared with 2 unicortical cancellous screws on a servohydraulic test frame in offset axial, transverse, and tension loading. Second, tension-band fixation using stainless steel wire was compared with FiberWire under tensile loads. Bicortical screw fixation was statistically the stiffest construct under tension loading conditions compared to unicortical screw fixation and tension-band techniques with FiberWire or stainless steel wire. In fact, unicortical screw fixation had only 10% of the stiffness as demonstrated in the bicortical technique. In a direct comparison, tension-band fixation using stainless steel wire was statistically stiffer than the FiberWire construct.


Asunto(s)
Articulación del Tobillo/cirugía , Fijación Interna de Fracturas/métodos , Fracturas Intraarticulares/cirugía , Dispositivos de Fijación Quirúrgicos , Fenómenos Biomecánicos , Tornillos Óseos , Hilos Ortopédicos , Humanos , Modelos Anatómicos , Diseño de Prótesis , Acero Inoxidable , Estrés Mecánico , Suturas , Resistencia a la Tracción , Tibia/cirugía
5.
Instr Course Lect ; 60: 35-42, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21553760

RESUMEN

Compartment syndrome of the calf has received a great deal of attention in the literature. A MEDLINE search was conducted to identify English-language publications pertaining to compartment syndrome of the leg and calf so that principles, recent evidence, and best practices for the diagnosis and treatment of this syndrome could be reviewed. Clinical series that reported outcomes and diagnostic criteria were reviewed and summarized. The currently available evidence is limited to level IV and V studies. Early diagnosis and treatment of compartment syndromes is associated with better results; however, many patients have chronic symptoms after treatment, even when the diagnosis is made promptly and fasciotomy is performed early. Although compartment syndrome of the leg and calf often has been described in the literature, prospective clinical series are lacking, and meaningful outcomes data are scarce. There is a need for further study on functional outcomes of acute compartment syndrome of the calf, with particular attention to diagnosis and treatment.


Asunto(s)
Síndromes Compartimentales/diagnóstico , Síndromes Compartimentales/terapia , Enfermedad Aguda , Current Procedural Terminology , Fasciotomía , Humanos , Pierna , Examen Físico , Recuperación de la Función , Resultado del Tratamiento
6.
Instr Course Lect ; 60: 43-50, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21553761

RESUMEN

Compartment syndromes of the forearm, gluteal region, thigh, and foot have not been extensively studied. To provide best-practice recommendations, the available evidence from four systematic reviews of English-language reports with two or more patients with compartment syndromes of the forearm, gluteal region, thigh, and foot were reviewed and compared. For each case of compartment syndrome, the cause, method of diagnosis, treatment options, and outcomes were determined. Most compartment syndromes were caused by trauma, with the exception of gluteal compartment syndrome, which usually resulted from prolonged immobilization and postarthroplasty analgesia. The diagnosis was often based on clinical findings, with compartment pressure measurements performed in approximately 50% of the patients. Compartment pressure measurements of the foot were more commonly obtained (in 64% of the patients). Compartment syndrome of the forearm and thigh were treated surgically in 73% and 100% of patients, respectively. Complications occurred with all four compartment syndromes, with nerve deficits and stiffness being the most common problems. Reports on functional outcomes lacked uniformity and did not allow for meaningful comparisons. Management principles for the less common compartment syndromes are the same as those used in treating compartment syndrome of the calf. Gluteal compartment syndrome usually has a nontraumatic etiology and is less likely to be surgically treated, probably because of major systemic complications and late presentation. Complications are common after these four types of compartment syndrome, but outcomes data are lacking.


Asunto(s)
Síndromes Compartimentales/diagnóstico , Síndromes Compartimentales/terapia , Extremidad Inferior , Extremidad Superior , Nalgas , Descompresión Quirúrgica , Enfermedades del Pie/diagnóstico , Enfermedades del Pie/terapia , Humanos , Examen Físico , Resultado del Tratamiento
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