Complicaciones en los alargamientos de miembros

El alargamiento óseo siempre ha sido en Cirugía Ortopédica a lo largo de los años un procedimiento caracterizado por el elevado número de complicaciones. Desde principio de siglo, muchos han sido los Ortopedas que han ideado métodos, aparatos y técnicas para conseguir un alargamiento del hueso pero las diferencias entre los métodos han marcado las complicaciones, secuelas y dificultades técnicas (1,2)

Epifisiodesis patológicas

Objetivo: Análisis retrospectivo de los casos de epifisiodesis patológicas diagnosticados en nuestro centro en el periodo desde enero de 1996 a diciembre de 2006. Material y métodos: El análisis se basa en determinar la distribución de los casos según la etiología, identificar el tipo de puente fisario siguiendo la clasificación de Ogden y considerar la actitud terapéutica en función de la deformidad. Resultados: Presentamos 61 casos de epifisiodesis patológicas, según la etiología: postraumática:16, infecciosa 24, congénita 8, iatrogénica 4, tumoral 5, otras causas 4. Según la localización de la lesión, fémur distal 15, fémur proximal 5, tibia proximal 14, tibia distal 12, calcáneo 1, falange pie 1, metatarsiano 1; húmero proximal 2; húmero distal 1; radio distal 3, cúbito distal 1, metacarpianos 3, falange de la mano 2. El tratamiento realizado fue distracción ósea, 15%, epifisiodesis, 8%; osteotomía correctora 23%; distracción fisaria 18%; desepifisiodesis 3% y 33% de los casos actitud expectante. Conclusiones: No debemos infravalorar esta lesión. La etiología es muy variada y el método de estudio se basa primero en la radiografía simple y como método auxiliar, la resonancia nuclear magnética, y por último, que existen múltiples alternativas terapéuticas, en función de la edad y la magnitud de la lesión.Purpose: Retrospective study of the pathologycal epiphysiodesis cases in our centre between January 1996 and December 2006. Materials and method: This analysis is based on determine the cases distribution according to etiology, to identify the physeal brigde kind according to Ogden´classification and to consider the treatment depending on the deformity. Results: We present 61 pathologycal epiphysiodesis cases; according to etiology posttraumatic16, infectious 24, congenital 8, iatrogenic 4, tumoral 5, other causes 4. According to lesion localitation: distal femur 15, proximal femur 5, proximal tibia 14, distal tibia 12, calcaneous 1, foot phalanx 1, metatarsal 1, proximal humerus 2, distal humerus 1, distal radius 3, distal ulna 1, metacarpal 3, hand phalanx 2. The treatment was osseous distraction 15%, epiphysiodesis 8%, correct osteotomy 23%, physeal distraction 18%, desepiphysiodesis 3% and expectant attitude on the rest of cases (33%). Conclusions: This lesion don´t underestimate. The etiology es very varied and the first study method is the simple radiography and RMN is the auxiliary method, and finally, there are a lot of therapeutic alternatives, according to the age and the dimension of the lesion

On the regularity of the covariance matrix of a discretized scalar field on the sphere

We present a comprehensive study of the regularity of the covariance matrix of a discretized field on the sphere. In a particular situation, the rank of the matrix depends on the number of pixels, the number of spherical harmonics, the symmetries of the pixelization scheme and the presence of a mask. Taking into account the above mentioned components, we provide analytical expressions that constrain the rank of the matrix. They are obtained by expanding the determinant of the covariance matrix as a sum of determinants of matrices made up of spherical harmonics. We investigate these constraints for five different pixelizations that have been used in the context of Cosmic Microwave Background (CMB) data analysis: Cube, Icosahedron, Igloo, GLESP and HEALPix, finding that, at least in the considered cases, the HEALPix pixelization tends to provide a covariance matrix with a rank closer to the maximum expected theoretical value than the other pixelizations. The effect of the propagation of numerical errors in the regularity of the covariance matrix is also studied for different computational precisions, as well as the effect of adding a certain level of noise in order to regularize the matrix. In addition, we investigate the application of the previous results to a particular example that requires the inversion of the covariance matrix: the estimation of the CMB temperature power spectrum through the Quadratic Maximum Likelihood algorithm. Finally, some general considerations in order to achieve a regular covariance matrix are also presented.Comment: 36 pages, 12 figures; minor changes in the text, matches published versio

Análisis de la mortalidad en pacientes con fracturas subcapitales de cadera

El objetivo del presente trabajo es realizar un estudio analítico restrospectivo de la mortalidad de una serie de 528 fracturas subcapitales de cadera en 523 pacientes tratados en nuestro centro mediante prótesis cérvico-cefálica cementada durante el periodo de 1978-1986. De estos 523 pacientes, 190 (36%) habían fallecido en el momento de realizar el estudio. Hemos analizado la mortalidad hospitalaria, 47 casos (9%) y 6 meses después de la intervención, 104 (20%). Se han demostrado como factores de alto riesgo: edad superior a 85 años, presentar tres o más enfermedades asociadas, complicaciones generales en el postoperatorio (escaras, tromboembolismo pulmonar, infarto agudo de miocardio, neumonía, etc.) complicaciones locales como la luxación de la prótesis y finalmente, una demora en la intervención superior a 6 días.We report a retrospective study analyzing the mortality of 528 femoral neck fractures in 523 patients treated with Thompson or Cathcart prosthesis during the period 1978-1986. The hospital mortality was 9% (47 cases) and 20% (104 cases) the mortality and six-months after surgery. High risk factors, were found to be: age more than 85 years-old, three o more preoperative illness, postoperative general complications (Pulmonar tromboembolism, Acute myocardial infarction, sores, pneumonia), dislocation of the prosthesis and a more than 6 days delay surgery

Rotura cuadricipital en edad pediátrica

La rotura del tendón del cuádriceps es una patología característica de la edad adulta, siendo excepcional en la infancia. Se presenta el caso de un niño de 9 años con una gonalgia izquierda de 2 meses de evolución sin claro antecedente traumático. Se realiza Resonancia Magnética, que establece el diagnóstico de rotura parcial del tendón del cuádriceps. Se decide reanclaje del mismo en el polo superior de la rótula, seguido de rehabilitación. Después del tratamiento quirúrgico realizado el paciente recupera el balance articular y muscular. La rotura del tendón del cuádriceps es excepcional en la edad pediátrica. La realización de una buena exploración, tanto clínica como radiológica es fundamental. El tratamiento viene determinado por el tipo de rotura y la clínica asociada. Hemos realizado una revisión bibliográfica de la literatura con el fin de dar a conocer este tipo de patología y su manejo.Rupture of the quadriceps tendon is a common pathology in adults, but exceptionally rare in children. The case reported is that of a 9-year old boy with a 2-month history of pain in the left knee without any clear history of trauma. Magnetic Resonance Imaging study was carried out, leading to the diagnosis of partial tear of the left quadricipital tendon. The tendon was re-anchored at the upper pole of the patella, followed by rehabilitation. The patient recovered joint and muscular balance after the surgery. Rupture of the quadriceps tendon is exceptionally rare at pediatric ages. A thorough examination, both clinical as well as radiological, is of fundamental importance. Treatment is determined by the kind of rupture and associated clinical symptoms. We have carried out a bibliographical review of the literature in order to offer a better understanding of this pathology and its treatment

Osteoporosis transitoria de la cadera: revisión de aspectos clínicos y terapéuticos a propósito de un caso

Presentamos el caso de una mujer de 17 años con osteoporosis transitoria de cadera (OTC). La OTC es una enfermedad infrecuente, difícil de etiquetar, que afecta a hombres sanos de mediana edad, y a mujeres en el tercer trimestre del embarzo. Su etiología todavía no está clara. Los principales signos clínicos son dolor en la cadera y cojera. La RM muestra en la cabeza y cuello femoral hipointensidad en las imágenes ponderadas en T1, e hiperintensidad en las imágenes ponderadas en T2. Se acepta que los cambios en la RM se producen por incremento de líquido en la cavidad medular de la cabeza femoral. Es importante el diagnóstico diferencial con otras enfermedades de la cadera. El propósito de esta publicación es aclarar los aspectos diagnósticos y terapéuticos de la OTC.A case of transient osteoporosis of the hips in a 17-year-old-woman is reported. Transient osteoporosis of the hip (TOH) is an uncommon but possibly underdiagnosed condition. The TOH affects previous healthy middle-age men, and women in the third trimester of pregnancy. Its etiology is still unclear. Pain in the hip area and limp are the main clinical signs. The MRI study shows low signal intensity on the Tl weighted images and limp signal intensity on the T2 weighted images in the femoral head and neck. It is generally accepted that the change in MRI is caused by an increase in fluid within the marrow cavities of the femoral head. Differential diagnosis of hip problems is required. The purpose of this report is to review the diagnostic and therapeutic aspects of TOH

Planck early results. XXIII. The first all-sky survey of Galactic cold clumps

33 páginas, 24 figuras, 9 tablas.-- Planck Collaboration: et al.We present the statistical properties of the Cold Clump Catalogue of Planck Objects (C3PO), the first all-sky catalogue of cold objects, in terms of their spatial distribution, dust temperature, distance, mass, and morphology. We have combined Planck and IRAS data to extract 10342 cold sources that stand out against a warmer environment. The sources are distributed over the whole sky, including in the Galactic plane, despite the confusion, and up to high latitudes (>30°). We find a strong spatial correlation of these sources with ancillary data tracing Galactic molecular structures and infrared dark clouds where the latter have been catalogued. These cold clumps are not isolated but clustered in groups. Dust temperature and emissivity spectral index values are derived from their spectral energy distributions using both Planck and IRAS data. The temperatures range from 7K to 19K, with a distribution peaking around 13K. The data are inconsistent with a constant value of the associated spectral index β over the whole temperature range: β varies from 1.4 to 2.8, with a mean value around 2.1. Distances are obtained for approximately one third of the objects. Most of the detections lie within 2kpc of the Sun, but more distant sources are also detected, out to 7kpc. The mass estimates inferred from dust emission range from 0.4 M⊙ to 2.4 × 105 M⊙. Their physical properties show that these cold sources trace a broad range of objects, from low-mass dense cores to giant molecular clouds, hence the “cold clump” terminology. This first statistical analysis of the C3PO reveals at least two colder populations of special interest with temperatures in the range 7 to 12K: cores that mostly lie close to the Sun; and massive cold clumps located in the inner Galaxy. We also describe the statistics of the early cold core (ECC) sample that is a subset of the C3PO, containing only the 915 most reliable detections. The ECC is delivered as a part of the Planck Early Release Compact Source Catalogue (ERCSC).Peer reviewe

Multi-resolution internal template cleaning: An application to the Wilkinson Microwave Anisotropy Probe 7-yr polarization data

Cosmic microwave background (CMB) radiation data obtained by different experiments contain, besides the desired signal, a superposition of microwave sky contributions. We present a fast and robust method, using a wavelet decomposition on the sphere, to recover the CMB signal from microwave maps. An application to \textit{WMAP} polarization data is presented, showing its good performance particularly in very polluted regions of the sky. The applied wavelet has the advantages of requiring little computational time in its calculations, being adapted to the \textit{HEALPix} pixelization scheme, and offering the possibility of multi-resolution analysis. The decomposition is implemented as part of a fully internal template fitting method, minimizing the variance of the resulting map at each scale. Using a $\chi^2$ characterization of the noise, we find that the residuals of the cleaned maps are compatible with those expected from the instrumental noise. The maps are also comparable to those obtained from the \textit{WMAP} team, but in our case we do not make use of external data sets. In addition, at low resolution, our cleaned maps present a lower level of noise. The E-mode power spectrum $C_{\ell}^{EE}$ is computed at high and low resolution; and a cross power spectrum $C_{\ell}^{TE}$ is also calculated from the foreground reduced maps of temperature given by \textit{WMAP} and our cleaned maps of polarization at high resolution. These spectra are consistent with the power spectra supplied by the \textit{WMAP} team. We detect the E-mode acoustic peak at $\ell \sim 400$, as predicted by the standard $\Lambda CDM$ model. The B-mode power spectrum $C_{\ell}^{BB}$ is compatible with zero.Comment: 8 pages, 6 figures. Some changes have been done from the original manuscript. This paper is accepted by MNRA

Tratamiento quirúrgico en las cifosis congénitas: Revisión de 14 pacientes

Los autores efectúan una revisión de 14 pacientes con cifosis congénita, intervenidos entre los años 1979-1989, con un seguimiento medio de 7 años. La edad media preoperatoria fue de 11 años (todos ellos mayores de 5 años), con una cifosis media de 7 9 . En 6 casos se realizó una artrodesis posterior y en 8 una anterior combinada con una fusión posterior. Inicialmente obtuvieron una corrección media de la curva de 18° con la artrodesis posterior y 20° con la artrodesis combinada. La pérdida postoperatoria final fue de 10° y 8° respectivamente. En un caso, se produjo una pseudoartrosis por fusión corta. Como complicaciones postoperatorias en 5 pacientes, una radiculopatía, una infección superficial y cuatro protusiones de material que requirieron su extracción. Los autores analizan los factores que han podido influir en los resultados obtenidos, comparándolos posteriormente con los conseguidos por otros centros hospitalarios importantes.Fourteen patients with congenital kyphosis treated surgically between 1979- 1989 were reviewed. All had a follow-up of 2 years or more, with an average follow-up of 7 years. The average age at surgery was 11 and the average kyphosis was 79°. Six cases had posterior fusion only and eigth had combined anterior and posterior fusion. The results showed an average correction of the curve at surgery of 18° with posterior arthrodesis and 20° with combined arthrodesis. There was thus an average loss of 10° and 8° respectively from the time of surgery in both types of treatment. Pseudoarthrosis by short fusion ocurred in one case. Other complications after surgery were 1 radiculopathy, one wound infection and four rod protusion (six patients). The factors that have influence in this results were analysed. A comparison from the results of treatment at other medical centers was also carried out

Las estructuras sociales de endeudamiento y los grupos de referencia comunitarios. Una comparación internacional

Aunque la sociología económica se ha interesado por la sociología de la deuda y del crédito, ha prestado poca atención a una definición sistemática de las estructuras sociales de endeudamiento y al papel que desempeñan en el contexto de los procesos de desarrollo económico. En el presente trabajo, se comienza discutiendo este concepto observando, a la luz de la evidencia empírica, las diversas formas que pueden adoptar estas estructuras. A partir de los datos recogidos por la encuesta ISSP 2001 realizada en 26 países, se profundiza en el estudio de los tipos de relación social de endeudamiento en función de los grupos de referencia (familiares, extrafamiliares, entidades bancarias) a los que los entrevistados dicen que acudirían en caso de que necesitasen una gran cantidad de dinero. Se estudian las orientaciones y los grupos de referencia de cada país en función de su nivel de desarrollo. Los resultados del análisis revelan la presencia de importantes contrastes entre estados con niveles de desarrollo muy diferentes y permiten descubrir pautas que muestran la presencia de espacios formales o informales de endeudamiento. La diversidad en la composición de los grupos de referencia refleja la variedad existente en las estructuras sociales de endeudamiento