Citoquinas proinflamatorias en la grasa articular y subcutánea del muslo en pacientes artrósicos / Pro-inflammatory cytokines in the knee fat pad and subcutaneous fat of the thigh in osteoarthritic patients

Resumen: Objetivo: Analizar el nivel de citoquinas proinflamatorias en la grasa articular del paquete adiposo en pacientes con gonartrosis, en relación con la grasa subcutánea del muslo. Material y métodos: Efectuamos un estudio de grasa del paquete adiposo articular de la rodilla afectada de artrosis y de la grasa subcutánea del muslo del mismo lado, a la mayor distancia de la articulación en seis pacientes con gonartrosis grave, con una edad media de 68 años (rango: 55-81 años). De las muestras de grasa se obtuvieron las células mesenquimales progenitoras. Los sobrenadantes de células mesenquimales obtenidas se utilizaron para analizar factores inflamatorios (IL-1b, IL6, IL8, IL9, IL1ra, IL12, IL13, IL15) y angiogénicos (VEGF, PDGF bb), así como citoquinas inmunomoduladoras (IP-10 e INF-γ) y se compararon las medias de dos muestras. Resultados: El análisis cuantitativo reveló una disminución significativa (p < 0.05) de IL-1b, IL6, IL8, IL9, IL1ra, IL12, IL13 y un aumento de IL15 en la grasa de Hoffa frente al tejido adiposo subcutáneo. Del mismo modo, el análisis de factores angiógenicos como VEGF y PDGF bb, al igual que los factores IP-10 e INF-γ presentaron una disminución significativa en la grasa de Hoffa (p < 0.05) frente al tejido adiposo subcutáneo. Discusión: Las células mesenquimales del paquete adiposo articular de la rodilla artrósica grave muestran una disminución significativa de citoquinas inflamatorias, aun en el estado crónico, y una disminución significativa de factores angiogénicos y citoquinas inmunomoduladoras (IP10 e INF).

Abstract: Objective: To analyze the level of pro-inflammatory cytokines in osteoarthritis knee joint fat pad in relation to the subcutaneous fat of the thigh. Material and methods: We performed a study of fat of the knee joint adipose affected of osteoarthritis and subcutaneous fat of the thigh of the same side to the greater distance of the joint in six patients with severe gonarthrosis, with a mean age of 68 years (range: 55-81 years). From the fat samples the progenitor mesenchymal cells were obtained. The supernatants of mesenchymal cells obtained to analyze inflammatory factors (IL-1b, IL6, IL9, IL1ra, IL12, IL13, IL15) and angiogenic (VEGF, PDGF bb) and immunomodulatory cytokines (IP-10 and INF-γ) means of two samples. Results: Quantitative analysis revealed a significant (p < 0.05) decrease in IL-1b, IL6, IL8, IL9, IL1ra, IL12, IL13 and increase of IL15 in Hoffa fat pad versus subcutaneous adipose tissue. Likewise, the analysis of angiogenic factors such as VEGF and PDGF, as well as factors IP-10 and INF-γ presented a significant decrease (p < 0.05) in Hoffa fat pad versus subcutaneous adipose tissue. Discussion: Mesenchymal cells from the adipose tissue of the severe osteoarthritic knee show a significant decrease in inflammatory cytokines even in the chronic state and a significant decrease in angiogenic factors and immunomodulatory cytokines (IP10 and INF).

Intrathecal administration of autologous bone marrow stromal cells improves neuropathic pain in patients with spinal cord injury.

Neuropathic pain (NP) is highly disabling, responds poorly to pharmacological treatment, and represents a significant cause of decreased quality of life in patients suffering from spinal cord injury (SCI). In recent years, cell therapy with autologous mesenchymal stromal cells (MSCs) has been considered as a potential therapeutic weapon in this entity. Ten patients suffering chronic SCI received 100 million MSCs into subarachnoid space by lumbar puncture (month 1 of the study) and this procedure was repeated at months 4 and 7 until reaching a total doses of 300 million MSCs. Intensity of NP was measured by standard numerical rating scale (VAS) from 0 to 10, recording scores previous to the first MSCs administration and monthly, until month 10 of follow-up. Months 1, 4, 7 and 10 of the study were selected as time points in order to a statistical analysis by the nonparametric Wilcoxon rank test. Our results showed significant and progressive improvement in NP intensity after the first administration of MSCs (p: 0.003). This study supports the benefit of intrathecal administration of autologous MSCs for the treatment of NP in patients with SCI.

Selective sentinel lymph node biopsy in male breast cancer. / Biopsia selectiva del ganglio centinela en el cáncer de mama del varón.

OBJECTIVE: To evaluate the reproducibility of the sentinel lymph node (SLN) technique in male breast cancer. MATERIAL AND METHODS: We retrospectively analysed 21 male patients diagnosed with breast cancer in our hospital from 2008 to 2016 with, at least, 18 months follow-up. Fifteen patients underwent selective sentinel lymph node biopsy (SLNB) following the usual protocols with peritumoral injection of 18.5-111MBq of 99mTc-nanocoloides and acquisition of planar images 2hours after the injection. In 2 cases it was necessary to perform a SPECT/CT to locate the SLN. Immunohistochemistry and molecular techniques (OSNA) were used for their analysis. Six patients did not undergo SLNB because they had pathological nodes or distant disease at the time of diagnosis. RESULTS: SLNB was performed in 15 patients. The SLN was negative in 6 patients and positive in the remaining 9. Three patients with positive SLNB did not need axillary lymphadenectomy because of the low number of copies by molecular analysis OSNA. Axillary lymphadenectomy was performed in the remaining 6 patients with the result of 4 positive axillary lymphadenectomies and 2 that did not show further extension of the disease. CONCLUSIONS: According to our experience, SLNB in males is a reproducible, useful, safe and reliable technique which avoids unnecessary axillary lymphadenectomy and prevents the appearance of undesirable effects.

Migración intraarticular del bloqueo óseo tibial tras la reconstrucción del ligamento cruzado anterior con injerto hueso-tendón-hueso / Intra-articular migration of a tibial bone block after an anterior cruciate ligament reconstruction using a bone-tendon-bone graft

Resumen: Presentamos el caso de una paciente que tras una reconstrucción del ligamento cruzado anterior (LCA) con injerto hueso-tendón-hueso (HTH) presentó una protrusión intraarticular del bloque óseo tibial en la radiografía postoperatoria de control. Se postuló la divergencia entre el túnel óseo tibial y el tornillo de interferencia como causa fundamental de la migración del injerto. Varios trabajos en modelos animales asocian dicho supuesto a una menor resistencia a la tracción. No se ha encontrado en la bibliografía médica publicada hasta la fecha ningún reporte clínico que describa esta complicación.

Abstract: We report the case of a patient that presented an intra-articular protrusion of the tibial bone block after an arthroscopically-assisted ACL reconstruction using a bone-patellar tendon-bone graft. The divergence between the tunnel and the screw was thought to be the reason of the migration. There are several animal-model studies that evidence a relationship between the decreased fixation of the graft and the tunnel-screw divergence. To the best of our knowledge, this is the first report of this complication.

Molecular markers of putative spermatogonial stem cells in the domestic cat.

Spermatogonial stem cells (SSCs) are an important tool for fertility preservation and species conservation. The ability to expand SSCs by in vitro culture is a crucial premise for their use in assisted reproduction. Because SSCs represent a small proportion of the germ cells in the adult testis, culture success is aided by pre-enrichment through sorting techniques based on cell surface-specific markers. Given the importance of the domestic cat as a model for conservation of endangered wild felids, herein we sought to examine culture conditions as well as molecular markers for cat SSCs. Using a cell culture medium for mouse SSCs supplemented with glial cell-derived neurotrophic factor (GDNF), germ cells from prepuberal cat testes remained viable in culture for up to 43 days. Immunohistochemistry for promyelocytic leukaemia zinc finger (PLZF) protein on foetal, prepuberal and adult testis sections revealed a pattern of expression consistent with the labelling of undifferentiated spermatogonia. Fluorescence-activated cell sorting (FACS) with an antibody against epithelial cell adhesion molecule (EPCAM) was used to sort live cells. Then, the gene expression profile of EPCAM-sorted cells was investigated through RT-qPCR. Notably, EPCAM (+) cells expressed relatively high levels of CKIT (CD117), a surface protein typically expressed in differentiating germ cells but not SSCs. Conversely, EPCAM (-) cells expressed relatively high levels of POU domain class 5 transcription factor 1 (POU1F5 or OCT4), clearly a germ line stem cell marker. These results suggest that cat SSCs would probably be found within the population of EPCAM (-) cells. Future studies should identify additional surface markers that alone or in combination can be used to further enrich SSCs from cat germ cells.

Role of the PDZ-scaffold protein NHERF1/EBP50 in cancer biology: from signaling regulation to clinical relevance.

The transmission of cellular information requires fine and subtle regulation of proteins that need to interact in a coordinated and specific way to form efficient signaling networks. The spatial and temporal coordination relies on scaffold proteins. Thanks to protein interaction domains such as PDZ domains, scaffold proteins organize multiprotein complexes enabling the proper transmission of cellular information through intracellular networks. NHERF1/EBP50 is a PDZ-scaffold protein that was initially identified as an organizer and regulator of transporters and channels at the apical side of epithelia through actin-binding ezrin-moesin-radixin proteins. Since, NHERF1/EBP50 has emerged as a major regulator of cancer signaling network by assembling cancer-related proteins. The PDZ-scaffold EBP50 carries either anti-tumor or pro-tumor functions, two antinomic functions dictated by EBP50 expression or subcellular localization. The dual function of NHERF1/EBP50 encompasses the regulation of several major signaling pathways engaged in cancer, including the receptor tyrosine kinases PDGFR and EGFR, PI3K/PTEN/AKT and Wnt-ß-catenin pathways.

[Pretibial pseudocyst after anterior cruciate ligament reconstruction with a biocomposite screw]. / Seudoquiste pretibial tras la reconstrucción del ligamento cruzado anterior con tornillo biocomposite.

We report the case of a patient who presented a pretibial extra-articular cyst two years after an arthroscopically assisted ACL reconstruction using an autologous bone-patellar tendon-bone graft. The tibial fixation was achieved with a bioabsorbable screw made of poly-L, D-lactic and -tricalcium phosphate (-TCP). A subcutaneous pseudocystic lesion was excised. It consisted of a capsular fibrous tissue with minimal milky fluid (1 ml) centrally. It penetrated into the tibial tunnel but did not communicate with the knee joint space. The histopathological analysis demonstrated fibrous tissue with multinucleated giant cells and refractile particles which suggested a foreign body reaction. After the surgery, the patient recovered perfectly well and he returned to his pre-injury level of physical activity in two months. To the best of our knowledge, this is the first report of this complication in a patient with a biocomposite screw made of poly-L, D-lactic and -tricalcium phosphate (-TCP).

Presentamos el caso de un paciente con un nódulo subcutáneo pretibial de unos 20 × 15 mm dos años después de la reconstrucción del ligamento cruzado anterior con un injerto autólogo hueso-tendón-hueso de tendón rotuliano fijado en la tibia con un tornillo de interferencia reabsorbible de ácido poli-D, L-láctico y fosfato -tricálcico. Se resecó una lesión seudoquística subcutánea con contenido líquido blanquecino y abundante fibrosis circundante, que penetraba en el túnel tibial sin comunicar con la articulación. El análisis anatomopatológico describió tejido fibroso con células multinucleadas y partículas refringentes, que sugería una reacción a cuerpo extraño. Después de la intervención, la sintomatología remitió y el individuo pudo recuperar su actividad deportiva previa en menos de dos meses. No se ha encontrado en la literatura médica publicada hasta la fecha ningún trabajo que describa esta complicación en un sujeto con un tornillo de interferencia tibial de ácido poli-D, L-láctico y fosfato -tricálcico.

[Non traumatic posterior instability in primary total knee replacement and its revision]. / Inestabilidad posterior no traumática de prótesis de rodilla primaria y su revisión.

BACKGROUND: Dislocation after total knee arthroplasty is a rare complication and a difficult problem to address. When the flexion gap is larger than the extension gap and the collateral ligaments are injured, instability and knee arthroplasty dislocation can occur. MATERIAL AND METHODS: We report the case of a patient presenting with a posterior dislocation of a posterior-stabilized prosthesis without trauma. Frank instability in varus stress test and a positive anterior drawer test with tibial internal rotation dismissed the conservative treatment. RESULTS: A constrained condylar prosthesis was used for the revision. He suffered a similar episode after a month, which demonstrated that the increase in the level of constraint was not enough to correct the severe asymmetric instability in flexion due to the damaged external structures. A rotating-hinge prosthesis was then implanted and the patient reported no additional episodes of instability. CONCLUSIONS: We made an exhaustive review of the literature, analyzed the possible causes that can lead to the tibiofemoral instability after a total knee arthroplasty and described some technical considerations.

La luxación tras la artroplastía de rodilla es una complicación poco frecuente y de difícil manejo. Una brecha en flexión demasiado grande asociada a una laxitud de los ligamentos colaterales puede llevar a la inestabilidad y a la luxación en flexión.

Seudoquiste pretibial tras la reconstrucción del ligamento cruzado anterior con tornillo biocomposite / Pretibial pseudocyst after anterior cruciate ligament reconstruction with a biocomposite screw

Resumen: Presentamos el caso de un paciente con un nódulo subcutáneo pretibial de unos 20 × 15 mm dos años después de la reconstrucción del ligamento cruzado anterior con un injerto autólogo hueso-tendón-hueso de tendón rotuliano fijado en la tibia con un tornillo de interferencia reabsorbible de ácido poli-D, L-láctico y fosfato β-tricálcico. Se resecó una lesión seudoquística subcutánea con contenido líquido blanquecino y abundante fibrosis circundante, que penetraba en el túnel tibial sin comunicar con la articulación. El análisis anatomopatológico describió tejido fibroso con células multinucleadas y partículas refringentes, que sugería una reacción a cuerpo extraño. Después de la intervención, la sintomatología remitió y el individuo pudo recuperar su actividad deportiva previa en menos de dos meses. No se ha encontrado en la literatura médica publicada hasta la fecha ningún trabajo que describa esta complicación en un sujeto con un tornillo de interferencia tibial de ácido poli-D, L-láctico y fosfato β-tricálcico.

Abstract: We report the case of a patient who presented a pretibial extra-articular cyst two years after an arthroscopically assisted ACL reconstruction using an autologous bone-patellar tendon-bone graft. The tibial fixation was achieved with a bioabsorbable screw made of poly-L, D-lactic and β-tricalcium phosphate (β-TCP). A subcutaneous pseudocystic lesion was excised. It consisted of a capsular fibrous tissue with minimal milky fluid (1 ml) centrally. It penetrated into the tibial tunnel but did not communicate with the knee joint space. The histopathological analysis demonstrated fibrous tissue with multinucleated giant cells and refractile particles which suggested a foreign body reaction. After the surgery, the patient recovered perfectly well and he returned to his pre-injury level of physical activity in two months. To the best of our knowledge, this is the first report of this complication in a patient with a biocomposite screw made of poly-L, D-lactic and β-tricalcium phosphate (β-TCP).

Inestabilidad posterior no traumática de prótesis de rodilla primaria y su revisión / Non traumatic posterior instability in primary total knee replacement and its revision

Resumen: Antecedentes: La luxación tras la artroplastía de rodilla es una complicación poco frecuente y de difícil manejo. Una brecha en flexión demasiado grande asociada a una laxitud de los ligamentos colaterales puede llevar a la inestabilidad y a la luxación en flexión. Material y métodos: Informamos del caso de un paciente que tuvo una luxación posterior de su prótesis de rodilla posteroestabilizada sin antecedente traumático. La inestabilidad franca al forzar el varo en flexión y un cajón anterior positivo que aumentaba en rotación interna condujeron a la revisión quirúrgica sin plantear un tratamiento conservador. Resultados: Se implantó una prótesis condilar constreñida tras lo cual sufrió un nuevo episodio de las mismas características un mes después, que puso de manifiesto que el nivel de constricción no fue suficiente para la inestabilidad severa en flexión asimétrica por insuficiencia de las estructuras externas. Luego de implantarle una prótesis tipo bisagra rotatoria, no ha tenido nuevos episodios de inestabilidad. Conclusiones: A través de un repaso exhaustivo de la bibliografía, se describen los posibles factores que pueden conducir a la inestabilidad tibiofemoral tras la artroplastía total de rodilla, así como las consideraciones técnicas para su manejo.

Abstract: Background: Dislocation after total knee arthroplasty is a rare complication and a difficult problem to address. When the flexion gap is larger than the extension gap and the collateral ligaments are injured, instability and knee arthroplasty dislocation can occur. Material and methods: We report the case of a patient presenting with a posterior dislocation of a posterior-stabilized prosthesis without trauma. Frank instability in varus stress test and a positive anterior drawer test with tibial internal rotation dismissed the conservative treatment. Results: A constrained condylar prosthesis was used for the revision. He suffered a similar episode after a month, which demonstrated that the increase in the level of constraint was not enough to correct the severe asymmetric instability in flexion due to the damaged external structures. A rotating-hinge prosthesis was then implanted and the patient reported no additional episodes of instability. Conclusions: We made an exhaustive review of the literature, analyzed the possible causes that can lead to the tibiofemoral instability after a total knee arthroplasty and described some technical considerations.

Influence of the cause of the revision on the outcome after revision knee arthroplasty with condylar constrained implant. / Influencia de la causa de revisión en el resultado tras revisión protésica de rodilla con implante varo-valgo constreñido.

INTRODUCTION: Revision total knee arthroplasty (TKA) is a common procedure with varying results depending on the cause. Our objective was to compare the clinical and radiological outcomes in patients undergoing aseptic revision versus revision due to prosthetic infection. MATERIAL AND METHODS: The study included 41 patients who underwent TKA revision with the same varus-valgus constrained implant. In all cases a clinical evaluation was performed including pain, range of motion (ROM), Knee Society Score (KSS), complications, as well as radiological study. A comparative analysis was performed on the pre- and postoperative results between septic and aseptic groups. The mean follow-up was 6 years. RESULTS: ROM had a mean increase of 17 degrees (p<.01). KSS and functional KSS improved significantly postoperatively. In the radiological study, joint interline and limb alignment were restored in all cases. Radiolucencies were found in 36.5% of cases; however they were unrelated to the appearance of loosening of the implant. There were complications in 29.2% of cases, mostly related to the surgical wound. Mobility, KSS, KSS functional and satisfaction at follow-up were better in the septic group. Implant survival was 95% at follow-up. CONCLUSION: Revision arthroplasty with constrained varus-valgus implant is safe, and has successful mid-term results despite the cause of the replacement procedure.

Early inflammatory response in polytraumatized patients: Cytokines and heat shock proteins. A pilot study.

INTRODUCTION: In the initial phases after polytrauma there is an hyperinflammatory state that sometimes leads to multiple organ dysfunction syndrome (MODS) and death, and that appears to be responsible for posttraumatic immunosuppression; among the trigger endogenous stimuli, heat shock proteins (HSPs) have been proposed. The objectives of this study were to analyze if some inflammatory mediators can be considered prognostic biomarkers of outcome, and the possible role of HSPA1A in posttraumatic immunosuppression. HYPOTHESIS: Cytokines and HSPs could be early prognostic biomarkers of inflammatory and immune response in polytrauma patients. MATERIALS AND METHODS: A prospective observational descriptive pilot study was carried out, evaluating the early inflammatory and stress response of 18 polytraumatized patients (ISS>16) on hospital admission, at 12hours, 24hours, and 48hours posttrauma. Variable means were compared using non-parametric tests; qualitative and quantitative variables were analyzed using a Spearman's correlation test. RESULTS: Seven patients met criteria for MODS. Statistically significant changes were recorded in leukocyte count, C-reactive-protein (CRP), IL-6, TNF-α, and IL-1ß concentrations. HSPA1A levels were significantly higher immediately after the accident followed by gradual lowering. Anti-Hsp70 antibodies showed a significant reduction in all the studied time-points. MODS did not influence either plasma levels of leukocytes, fibrinogen, RCP or anti-Hsp70, but patients with MODS had higher plasma levels of IL-6 and TNF-α and a slower decrease of HSPA1A concentrations. DISCUSSION: The higher serum concentrations of TNF-α and IL-6 found in patients with MODS, suggests a possible role as potential early predictive markers for systemic inflammatory response and clinical complications. The higher levels of HSPA1A in patients with MODS, allows proposing HSPA1A as a useful prognostic trauma biomarker early after severe injury and to consider a "damage control surgery". The significant reduction in the levels of anti-Hsp70 antibodies could reflect a part of posttraumatic immunosuppression and hydrocortisone treatment might be suggested. LEVEL III: case-control study.

Development and validation of an open source quantification tool for DSC-MRI studies.

MOTIVATION: This work presents the development of an open source tool for the quantification of dynamic susceptibility-weighted contrast-enhanced (DSC) perfusion studies. The development of this tool is motivated by the lack of open source tools implemented on open platforms to allow external developers to implement their own quantification methods easily and without the need of paying for a development license. MATERIALS AND METHODS: This quantification tool was developed as a plugin for the ImageJ image analysis platform using the Java programming language. A modular approach was used in the implementation of the components, in such a way that the addition of new methods can be done without breaking any of the existing functionalities. For the validation process, images from seven patients with brain tumors were acquired and quantified with the presented tool and with a widely used clinical software package. The resulting perfusion parameters were then compared. RESULTS: Perfusion parameters and the corresponding parametric images were obtained. When no gamma-fitting is used, an excellent agreement with the tool used as a gold-standard was obtained (R(2)>0.8 and values are within 95% CI limits in Bland-Altman plots). CONCLUSION: An open source tool that performs quantification of perfusion studies using magnetic resonance imaging has been developed and validated using a clinical software package. It works as an ImageJ plugin and the source code has been published with an open source license.

[Salivaly gland tumors in childhood: importance of an early diagnosis and treatment]. / Tumores de glándulas salivales en la infancia. Importancia de un diagnóstico y tratamiento precoz.

OBJECTIVE: Review of our series of salivaly gland tumors at pediatric age, given its low frequency and their higher rate of malignancy compared with the adult population. MATERIAL AND METHODS: Retrospective study of the medical records of all pediatric patients with salivaly gland tumors treated in our center between 1998 and 2013. RESULTS: We identified 12 patients. The most common site of tumor location was the parotid gland in 11 patients followed by the sublingual gland in 1 patient. Three patients had previous cancer and radiotherapy history. The diagnosis (histological or radiological) were: 4 hemangiomas, 2 pleomorphic adenomas, 4 mucoepidermoid carcinomas, one acinar cell carcinoma and 1 primitive neuroectodermal tumor (PNET). No patient had metastasis at diagnosis. Preoperative fine needle aspiration (FNA) was performed in 6 patients with solid masses, being diagnostic in all cases. Eight patients underwent surgery. In two cases of total parotidectomy initial neuroapraxia appeared but none had permanent facial paralysis. There were no cases of Frey syndrome. The aesthetic results were good. There was only one tumor recurrence and all patients, except one who died of leukemia relapse, survive today. CONCLUSIONS: Salivaly gland tumors are uncommon in pediatric age but their high rate of malignancy makes it necessary to establish a rapid diagnosis. In our experience, FNA showed a high sensitivity. For malignant tumors, definitive treatment is surgical excision, preserving the facial nerve whenever possible. For vascular tumors, surgery is reserved for cases refractory to medical treatment.

OBJETIVO: Revisión de nuestra serie de neoplasias de glándulas salivales en pediatría, dada su baja frecuencia y mayor tasa de malignidad en comparación con la población adulta. MATERIAL Y METODOS: Estudio retrospectivo de las historias clínicas de los casos pediátricos de tumores de glándulas salivales tratados en nuestro centro entre los años 1998 y 2013. RESULTADOS: Se estudian 12 pacientes. Los tumores afectaban a la glándula parótida en 11 casos y en uno a la glándula sublingual. Tres pacientes presentaban historia oncológica previa y antecedentes de radioterapia. El diagnóstico (histológico o radiológico) fue de: 4 hemangiomas, 2 adenomas pleomorfos, 4 carcinomas mucoepidermoides, 1 carcinoma de células acinares y 1 tumor primitivo neuroectodérmico (PNET). Ningún paciente presentaba metástasis al diagnóstico. Se realizó PAAF preoperatoria en 6 pacientes que presentaban masas sólidas, siendo diagnóstica en todos ellos. Ocho pacientes fueron intervenidos. En dos casos de parotidectomía total apareció neuroapraxia inicial pero ninguno tuvo parálisis facial definitiva. No hubo ningún caso de síndrome de Frey. Los resultados estéticos fueron buenos. Un solo caso presentó recidiva tumoral y todos los pacientes, excepto uno que falleció por recaída de leucemia, sobreviven en la actualidad. CONCLUSIONES: Los tumores de glándula salival son raros en pediatría pero su alta tasa de malignidad hace necesario establecer un diagnóstico rápido. En nuestra experiencia, la PAAF presentó elevada sensibilidad. En los tumores malignos el tratamiento es la exéresis, preservando el nervio facial siempre que sea posible. En los tumores vasculares la cirugía se reserva para casos refractarios al tratamiento médico.

[Removal due to cut-out effect in pertrochanteric femoral fractures: what is the rescue treatment of choice?]. / Desmontaje por efecto cut-out en el enclavado de fracturas pertrocantéreas de fémur: ¿cuál es el tratamiento de rescate de elección?

OBJECTIVE: The goal of the study was to compare functional results in different treament options in cutting-out, and analize factors associated to failure. MATERIAL AND METHODS: Retrospective cohort study in 56 patients diagnosed with cutting-out between 2000-2010. Groups were based on rescue treatment: arthroplasty versus alternative treatment. Demographics, fracture characteristics, osteosynthesis, tip to apex distance (TAD), follow-up, complications, and final functional capacity were analyzed. RESULTS: Rescue treatment: 36 (64.28%) hip replacement (arthroplasty group), and 20 (35.72%) alternative treatment preserving femoral head (alternative group). Groups comparable on demographic parameters, fracture pattern and osteosynthesis characteristics. Radiography analysis: low inter-observer variability (k=0.83, 95% CI 0.78-0.88), mean TAD 28.66mm (arthroplasty group 32.9mm, 21.5mm control group; p=0.01), insufficient fracture reduction 39.3% (p=0.001). Cutting-out diagnosis median 60 days (arthroplasty group 90 days, 18 days alternative group; p=0.001). Follow up at least 12 months from rescue treatment. Similar complications rate in both groups (p=0.16). Re-operation rate 3.57% (11.7% arthroplasty group, alternative group 0%; p=0.01). Better final functional capacity in arthroplasty group (p=0.004). DISCUSSION: Hip arthroplasty offers better results, being considered the gold standard in geriatric patients, although re-operation rate is higher. We recommend new nailing before arthroplasty in early failure (4 weeks) in patients with femoral head integrity. An insufficient fracture reduction is the main short term factor predicting failure; and TAD higher than 20mm is a middle-long term one.

Modification of the TASMIP x-ray spectral model for the simulation of microfocus x-ray sources.

PURPOSE: The availability of accurate and simple models for the estimation of x-ray spectra is of great importance for system simulation, optimization, or inclusion of photon energy information into data processing. There is a variety of publicly available tools for estimation of x-ray spectra in radiology and mammography. However, most of these models cannot be used directly for modeling microfocus x-ray sources due to differences in inherent filtration, energy range and/or anode material. For this reason the authors propose in this work a new model for the simulation of microfocus spectra based on existing models for mammography and radiology, modified to compensate for the effects of inherent filtration and energy range. METHODS: The authors used the radiology and mammography versions of an existing empirical model [tungsten anode spectral model interpolating polynomials (TASMIP)] as the basis of the microfocus model. First, the authors estimated the inherent filtration included in the radiology model by comparing the shape of the spectra with spectra from the mammography model. Afterwards, the authors built a unified spectra dataset by combining both models and, finally, they estimated the parameters of the new version of TASMIP for microfocus sources by calibrating against experimental exposure data from a microfocus x-ray source. The model was validated by comparing estimated and experimental exposure and attenuation data for different attenuating materials and x-ray beam peak energy values, using two different x-ray tubes. RESULTS: Inherent filtration for the radiology spectra from TASMIP was found to be equivalent to 1.68 mm Al, as compared to spectra obtained from the mammography model. To match the experimentally measured exposure data the combined dataset required to apply a negative filtration of about 0.21 mm Al and an anode roughness of 0.003 mm W. The validation of the model against real acquired data showed errors in exposure and attenuation in line with those reported for other models for radiology or mammography. CONCLUSIONS: A new version of the TASMIP model for the estimation of x-ray spectra in microfocus x-ray sources has been developed and validated experimentally. Similarly to other versions of TASMIP, the estimation of spectra is very simple, involving only the evaluation of polynomial expressions.

[Influence of the physiological medium on the mechanical properties of bone cement: can current studies be extrapolated?]. / Influencia del medio fisiológico sobre las propiedades mecánicas del cemento óseo. ¿Son los estudios actuales extrapolables?

PURPOSE: The use of bone cement is widespread in orthopaedic surgery. Most of the mechanical tests are performed in dry medium, making it difficult to extrapolate the results. The objective of this study is to assess if the mechanical properties of polymethylmethacrylate (PMMA), obtained in previous reports, are still present in a liquid medium. MATERIAL AND METHOD: An experimental study was designed with antibiotic (vancomycin) loaded PMMA. Four groups were defined according to the medium (dry or liquid) and the pre-conditioning in liquid medium (one week or one month). Wear and flexural strength tests were performed according to ASTM and ISO standards. Volumetric wear, friction coefficient, tensile strength, and Young's modulus were analyzed. All samples were examined by scanning electron microscopy. RESULTS: The samples tested in liquid medium showed lower wear and flexural strength values (P<.05). The kind of wear was modified from abrasive to adhesive in those samples studied in liquid medium. The samples with a pre-conditioning time showed lower values of wear (P<.05). CONCLUSIONS: Caution is recommended when extrapolating the results of previous PMMA results. The different mechanical strength of the cement in a liquid medium, observed in saline medium, is much closer to the clinical situation.

[SECOT consensus on painful knee replacement]. / Consenso SECOT sobre artroplastia de rodilla dolorosa.

The opinions of 21 experts in knee surgery were evaluated in this study, using a DELPHI questionnaire method in two successive rounds, on 64 controversial scenarios that covered both the diagnosis and possible treatment of painful knee replacements. The level of consensus was significantly unanimous in 42 items and of the design in 5, with no agreement in 17 of the questions presented. light of the published scientific evidence, the surgeons who took part showed to have a notable level of information on the most effective diagnostic tests, although, it should be pointed out that there was a lack of confidence in the possibility of ruling out an infection when the erythrocyte sedimentation rate and the C-reactive protein were within normal values, which have been demonstrated in the literature to have a high negative predictive value As regards the treatments to employ in the different situations, the responses of the expert panel were mainly in agreement with the data in the literature. The conclusions of this consensus may help other surgeons when they are faced with a painful knee prosthesis.