Review of some classical gravitational superenergy tensors using computational techniques

We use computational algorithms recently developed by us to study completely four index divergence free quadratic in Riemann tensor polynomials in GR. Some results are new and some other reproduce and/or correct known ones. The algorithms are part of a Mathematica package called Tools of Tensor Calculus (TTC)[web address: http://baldufa.upc.es/ttc

Pseudoaneurismas femorales en fracturas de cadera. ¿Se puede evitar?

Aunque la aparición de un pseudoaneurisma femoral es infrecuente en el contexto del tratamiento de fracturas pertrocantéreas, debido a su extrema gravedad y a su posible implicación en las causas de mortali - dad, es necesario realizar un diagnóstico temprano y un tratamiento adecuado. Presentamos 3 casos en los que se produjo una lesión de la arteria femoral superficial, y 2 de la arteria femoral profunda, tratados los 3 casos con stents recubiertos. Conclusiones . Se debe tomar en consideración, recti fi car la aducción y rotación interna de la extremidad fracturada una vez colocado el implante, el uso de brocas cortas o con un tope para el momento del en - cerrojado distal, longitud adecuada de los tornillos, controlar el desplazamiento del trocánter menor, o una correcta colocación de los cerclajes femorales, para poder disminuir la incidencia de este tipo de lesiones.Although the appearance of a femoral pseudoaneurysm is uncommon in the context of treatment of trochanteric fractures, due to their extreme gravity and its possible involvement in the causes of death, it is ne - cessary for early diagnosis and appropriate treatment. We report 3 cases in which an injury occurred superficial femoral artery, and 2 of the deep femoral artery, 3 cases treated with stents. Conclusions. It should be taken into consideration, correct adduction and internal rotation of the fractured limb once fitted the implant, the use of short bits or a cap on the distal locking time, proper length screws, control the displacement of the lesser trochanter , or the correct placement of the femoral cerclage, to decrease the incidence of these injuries

Luxación anterior de cadera: presentación de un caso y revisión de la literatura.

La luxación anterior de cadera es una lesión poco frecuente y que se produce por traumatismos de alta energía. Este tipo de luxación requiere maniobras especiales para su reducción. El tratamiento ortopédico puede dar buenos resultados, aunque en ocasiones es necesaria la reducción abierta y el tratamiento quirúrgico de lesiones asociadas. Presentamos el caso de un varón de 27 años que presentaba una luxación anterior de cadera derecha debido a accidente automovilístico. Además tenía lesiones asociadas en pie derecho. Se realizó reducción cerrada y tratamiento conservador con buenos resultados. El pronóstico de una luxación de cadera depende de la gravedad de la lesión así como del tiempo que se tarda en realizar la reducción, que está relacionando con el riesgo de desarrollo de necrosis avascular. La luxación anterior de cadera tiene mejor pronóstico que la luxación posterior cuando se realiza un tratamiento temprano adecuado.The anterior hip dislocation is a little frequent injury and is produced by high energy traumatisms. This type of dislocation requires special maneuvers for its reduction. The orthopaedic treatment can give good results, although sometimes it is necessary the open reduction and the surgical treatment of associate injuries. We present a case of a 27 year-old man who presented an anterior hip dislocation due to automobile accident. He had associated injuries on right food. He was treated by closed reduction and orthopaedic treatment and he had good results. The prognosis of a hip dislocation depends on the gravity of the injury as well as the time that takes in realizing the reduction, that it is relating to the risk of development of avascular necrosis. The anterior hip dislocation has better prognosis than the posterior dislocation when a suitable treatment is early realized

Osteoporosis transitoria migratoria de cadera: a propósito de un caso

La osteoporosis transitoria asociada a la gestación es una condición poco usual, idiopática y auto - limitada. Comúnmente asociada al tercer trimestre del embarazo y al periodo postparto; cursa con dolor migra - torio en las articulaciones de carga, osteopenia radiográfica difusa periarticular y patrón de edema medular óseo en la RMN. Presentamos el caso clínico de una mujer de 28 años, en la semana 34 de gestación, que tras una leve caída presenta dolor y limitación funcional en miembro inferior derecho. En la RMN se evidencia edema óseo a nivel del extremo proximal de fémur derecho. Se trató de forma conservadora, mediante reposo y marcha con andador en descarga, programándose fijación profiláctica en quirófano. Al cabo de dos semanas de su ingreso, sin haber sido intervenida aún, inicia dolor en cadera contralateral. Se realiza nueva RMN donde se observa edema en cabeza y región intertrocantérica izquierda, con mejoría de los hallazgos previos en la cadera derecha. Se suspende tratamiento quirúrgico y se indica reposo absoluto con manejo expectante. A las 9 semanas de inicio del cuadro y 8 semanas postparto la paciente se encuentra asintomática y realiza su actividad diaria sin limitaciones. Un alto índice de sospecha y un diagnóstico precoz son la clave para evitar una fractura como resultado de la osteoporosis transitoria. La resonancia magnética es la mejor herramienta no invasiva para las mujeres embara - zadas con dolor en la cadera. La detección temprana puede prevenir las complicaciones y evitar cirugías mayoreTransient osteoporosis of the hip is a rare condition, idiopathic and self-limiting disease. This malady (complaint, disorder) is more common in the third trimester of pregnancy and postpartum. Characterized by migratory pain in bearing joints, periarticular osteopenia and diffuse radiographic pattern of bone marrow edema on MR. We report the case of a woman 28 years old, in the 34th week of her pregnancy, who after a fall, presents pain and functional limitation in her right leg. The MR showed bone edema at the proximal right femur. She was treated with rest and a walker, and she was scheduled for prophylactic fixation in the operating room in a few weeks. Two weeks after hospital admission, left hip started aching. A new MR showed edema in the head and intertrochanteric region of the left hip, with improvement of previous findings in the right hip. Surgical treatment was cancelled and bed rest was suggested as expectant management. At 9 weeks of onset of symptoms and 8 weeks postpartum, the patient was asymptomatic and performs daily activities without limitations. High index of suspicion and early diagnosis is the key to avoid fracture as a result of transient osteoporosis. Magnetic resonance imaging is the best non-invasive tool for pregnant women with hip pain. Early detection of the disease can avoid complications and major surgeries

Bifosfonatos y fracturas femorales de baja energía: la experiencia en nuestro centro

Los bifosfonatos son fármacos de uso común para la prevención de fracturas osteoporóticas. En los últimos años ha sido relacionado su consumo prolongado con la aparición de fracturas de baja energía en fémur con un trazo característico transverso. Para evaluar esta relación hemos analizado las fracturas de fémur de baja energía atendidas en nuestro centro durante 2 años y relacionándolas con el consumo previo de bisfosfonatos. En fracturas subtrocantéras no se observan diferencias significativas; en diafisarias, las fracturas trazo transverso típico se presentan en pacientes de menor edad y significativamente asociados al consumo previo de bifosfonatos (6 de las 8 fracturas de este tipo pensaban historia de consumo prolongado de estos fármacos). Como conclusión, aunque se han publicado numerosos artículos en los últimos años con series de casos que relacionan este tipo de fracturas con el consumo previo de bifosfonatos, el tamaño muestral de los estudios y las dificultades de evaluar el consumo de un fármaco retrospectivamente hacen necesarios estudios aleatorizados y prospectivos para dejar evidencia de la posible relaciónBisphosphonates are commonly used drugs for the prevention of osteoporotic fractures. In recent years, consumption has long been linked with the emergence of low-energy fractures of the femur with a characteristic transverse line. To evaluate this relationship we have analyzed the femur fractures treated low energy in our center for 2 years and related to the prior use of bisphosphonates. In subtrochanteric fractures, no significant differences were found; in diaphyseal fractures are typically transverse line is present in younger patients and significantly associated with prior use of bisphosphonates (6 of 8 thought this type fractures history of prolonged use of these drugs). In conclusion, although there have been numerous articles in the last years series of cases this type of fracture associated with prior use of bisphosphonates, the sample size of studies and the difficulties of assessing a drug consumption retrospective studies are needed prospective randomized to leave evidence of the possible association

Fijador externo como tratamiento definitivo de fractura de diáfisis femoral en Enfermedad de Paget

El tratamiento de las fracturas en la enfermedad de Paget presenta dificultades para el cirujano, debido a las características patológicas del hueso en este tipo de pacientes. La opción terapéutica de elección en fracturas de diáfisis femoral es el enclavado endomedular, pero a menudo encontramos en esta enfermedad complicaciones que dificultan la técnica quirúrgica. Presentamos el caso de una paciente con fractura de diáfisis femoral en hueso con características pagéticas, en el que por la estrechez del canal y la dureza de las corticales no fue posible realizar en enclavado endomedular, y se optó por el fijador externo como tratamiento definitivo, con buenos resultados radiográficos y funcionales. Tras el primer año de evolución, observamos una buena consoli - dación ósea en la radiografía, y la paciente deambula sin ayuda.The treatment of fractures in Paget's disease presents difficulties for the surgeon because of the pathological features of bone in these patients. The treatment of choice for femoral shaft fractures is intrame - dullary nailing, but often found in this disease, complications that hinder the surgical technique. We report the case of a patient with femoral shaft fracture in bone with pagetic characteristics, in which because of the narrow canal and the hardness of the cortical, intamedullary nailing was not possible. We opted for the external fixator as definitive treatment, with good radiographic and functional results. After the first year of follow up, we see good bone healing on X-ray and the patient ambulate without help

On the structure of the new electromagnetic conservation laws

New electromagnetic conservation laws have recently been proposed: in the absence of electromagnetic currents, the trace of the Chevreton superenergy tensor, $H_{ab}$ is divergence-free in four-dimensional (a) Einstein spacetimes for test fields, (b) Einstein-Maxwell spacetimes. Subsequently it has been pointed out, in analogy with flat spaces, that for Einstein spacetimes the trace of the Chevreton superenergy tensor $H_{ab}$ can be rearranged in the form of a generalised wave operator $\square_L$ acting on the energy momentum tensor $T_{ab}$ of the test fields, i.e., $H_{ab}=\square_LT_{ab}/2$. In this letter we show, for Einstein-Maxwell spacetimes in the full non-linear theory, that, although, the trace of the Chevreton superenergy tensor $H_{ab}$ can again be rearranged in the form of a generalised wave operator $\square_G$ acting on the electromagnetic energy momentum tensor, in this case the result is also crucially dependent on Einstein's equations; hence we argue that the divergence-free property of the tensor $H_{ab}=\square_GT_{ab}/2$ has significant independent content beyond that of the divergence-free property of $T_{ab}$

The Chevreton Tensor and Einstein-Maxwell Spacetimes Conformal to Einstein Spaces

In this paper we characterize the source-free Einstein-Maxwell spacetimes which have a trace-free Chevreton tensor. We show that this is equivalent to the Chevreton tensor being of pure-radiation type and that it restricts the spacetimes to Petrov types \textbf{N} or \textbf{O}. We prove that the trace of the Chevreton tensor is related to the Bach tensor and use this to find all Einstein-Maxwell spacetimes with a zero cosmological constant that have a vanishing Bach tensor. Among these spacetimes we then look for those which are conformal to Einstein spaces. We find that the electromagnetic field and the Weyl tensor must be aligned, and in the case that the electromagnetic field is null, the spacetime must be conformally Ricci-flat and all such solutions are known. In the non-null case, since the general solution is not known on closed form, we settle with giving the integrability conditions in the general case, but we do give new explicit examples of Einstein-Maxwell spacetimes that are conformal to Einstein spaces, and we also find examples where the vanishing of the Bach tensor does not imply that the spacetime is conformal to a $C$-space. The non-aligned Einstein-Maxwell spacetimes with vanishing Bach tensor are conformally $C$-spaces, but none of them are conformal to Einstein spaces.Comment: 22 pages. Corrected equation (12

Experiencia con test de artrografía intraoperatoria para valorar la rotura de la sindesmosis tibioperonea

Ankle fractures frequently associate tibiofibular syndesmosis injuries, whose diagnosis allows intraoperative treatment that can prevent mid-long term complications. There are several clinical diagnostic tests and specific projections but they are difficult to interpret and standardize. The objective of the study is to evaluate a recently described intraoperative diagnostic test. We conducted the test by intraarticular contrast injection in ten patients with fractures type Weber B or C. The test was valuable in 8 cases and the result coincided with the other clinical test used. We detected a fracture in one case that had gone undetected and resulted in a change of treatment. There were no complications. Using a reproducible, cheap and safe test, we can obtain an easily interpretable image that complements the rest of clinical tests to support the surgeon in the decision to fix the sindesmosis in ankle fractures