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1.
J Child Orthop ; 14(5): 459-465, 2020 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-33204354

RESUMEN

PURPOSE: The article compares physeal recovery after insertion of autologous cartilage and a conventional fat graft in a standardized porcine physeal gap model. Presence of a bone bridge was the primary outcome. METHODS: Ten porcines in two groups of five were included in a paired design. A standardized physeal gap in the distal femur was made in all animals. One group (n = 5) was randomized for deposition of autologous cartilage and a Tisseel® or Tisseel® alone. The autologous cartilage was harvested from the femoral articular surface. The other group was randomized for fat grafting or no grafts at all. All animals were housed for 14 weeks. Magnetic resonance imaging (MRI) was performed at 14 weeks prior to euthanasia. The physis was harvested for histology. RESULTS: MRI - Three bone bridges were seen in the fat grafted gaps. All empty gaps formed a bone bridge. No gaps filled with autologous cartilage and Tisseel® resulted in bone bridges. One gap filled with Tisseel® only caused a bone bridge. Histology - The cartilage grafted gaps recovered with physeal-like cartilaginous tissue in histological analysis. CONCLUSIONS: Fat grafts seems ineffective in preventing bone bridges. The use of autologous cartilage may be superior to the current treatment. However, donor site complications were not investigated. The study serves as a proof of concept study and requires further investigation. LEVEL OF EVIDENCE: III.

2.
J Sci Food Agric ; 99(7): 3628-3634, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30628081

RESUMEN

BACKGROUND: Phosphorus (P) supply is essential for bone mineralisation. Reduced P may result in osteopenia, whereas excessive P may result in environmental impacts. The objective was to study the long-term effect of three dietary P levels on net bone mineralisation in growing-finishing pigs. Eighteen female pigs were fed low P (LP (4.1)), medium P (MP (6.2)) or high P (HP (8.9 g P kg-1 DM)) from 39.7 until 110 kg. Trabecular, cortical and overall bone mineral density (BMD), ash, calcium (Ca) and P were determined after slaughter. RESULTS: The LP diet generally reduced the BMD, ash, Ca and P in all bones, though all measures were markedly lowered in femur compared with humerus. The trabecular BMD in LP pigs was only different in the distal section compared to the MP-fed pigs (P < 0.05). In addition, ash, Ca and P were lower in the proximal and distal sections. No significant effect of HP was seen. Conclusively, LP caused lower net bone mineralisation, mainly of femur. The trabecular tissue of the distal bones seems to be most metabolically active. CONCLUSIONS: The MP level was sufficient for net bone mineralisation. Femur is recommended for studying bone fragility whereas humerus seems useful to study increased P retention. © 2019 The Authors. Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Asunto(s)
Huesos/metabolismo , Fósforo Dietético/metabolismo , Porcinos/metabolismo , Alimentación Animal/análisis , Animales , Densidad Ósea , Desarrollo Óseo , Calcio de la Dieta/análisis , Calcio de la Dieta/metabolismo , Femenino , Fósforo Dietético/análisis , Porcinos/crecimiento & desarrollo
3.
eNeurologicalSci ; 14: 62-67, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30671550

RESUMEN

Our objective is to review the initial presentation, evolution, progression, final stage, and images in the follow up of an adult patient who presented an uncommon peroxisomal disease (1/20,000 males) that occurred by ABCD1 gene mutation in the Xq28 chromosome; to bring forward the imaging features (which nowadays is the most useful and accessible diagnostic tool) and clinical presentation of adrenoleukodystrophy in adulthood; to propose a differential diagnosis in aid of a prompt recognition of the disease hereafter from a neurologist approach. In relation of a clinical case we reviewed the literature to correlate the principal findings and evolution of the disease. This thrilling but at the same time unfortunate disease is not only a diagnostic problem is also a therapeutic quest besides all the related familial, labor, and social related problems. The very-long chain fatty acids (VLCFA) accumulation leads to a not completely understood mechanisms that precipitate the specific malfunction of the nervous system and adrenal gland. The initial corticospinal bilateral involvement provokes a spastic paraparesis but with the affection of others pathways multiple manifestations appears, with dementia and finally loss of the most of cortical functions secondary to the white matter affection. Since the hematopoietic stem cell transplantation can be treated with variable results, other treatments, as the Lorenzo's oil, have not been consistent with a substantial improvement of the affected individual. The genetic advice and support to the patient and the family are essentials as well as the screening in individuals at risk before the onset of the disease.

4.
BMC Musculoskelet Disord ; 18(1): 441, 2017 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-29132335

RESUMEN

BACKGROUND: Initial micromotion of a total hip replacement is associated with aseptic loosening. The use of bisphosphonates could be one way to reduce peri-implant bone resorption induced by micromotion. Bisphosphonates compounds are inhibitors of bone resorption. The aim of this study was to investigate whether local treatment with bisphosphonate would reduce bone resorption and fibrous tissue around an experimental implant subjected to micromotion. METHODS: One micromotion implant were inserted into each medial femoral condyle in ten sheep. During each gait cycle the implant axially piston 0.5 mm. During surgery one of the femoral condyles were locally treated with 0.8 mg zoledronate. The other condyle served as control. Observation period was 12 weeks. RESULTS: Histological evaluation showed a fibrous capsule around both the control and bisphosphonate implants. Histomorphometrical analysis showed that 97% of the surface on both control and bisphosphonate implants were covered by fibrous tissue. However, the bisphosphonate was able to preserve bone in a 1 mm zone around the implants. CONCLUSION: This study indicates that local treatment with bisphosphonate cannot prevent the formation of a fibrous capsule around an implant subjected to micromotion, but bisphosphonate is able to reduce resorption of peri-prosthetic bone.


Asunto(s)
Conservadores de la Densidad Ósea/uso terapéutico , Resorción Ósea/prevención & control , Difosfonatos/uso terapéutico , Imidazoles/uso terapéutico , Animales , Conservadores de la Densidad Ósea/farmacología , Difosfonatos/farmacología , Evaluación Preclínica de Medicamentos , Fibrosis , Imidazoles/farmacología , Falla de Prótesis/efectos de los fármacos , Ovinos , Ácido Zoledrónico
5.
J Orthop Traumatol ; 18(2): 121-126, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27709362

RESUMEN

BACKGROUND: Several treatments have been described for leg length discrepancy. Epiphysiodesis is the most commonly used because of its effectiveness. Thermal epiphysiodesis using radiofrequency ablation (RFA) alters the growth plate morphology without damaging the adjacent articular cartilage; it is a minimally invasive method that has shown excellent results in animal models. This study describes the macro and micro morphology after the procedure. MATERIALS AND METHODS: Epiphysiodesis using RFA was performed in vivo for 8 min (92-98 °C) at two ablation sites (medial and lateral) in one randomly-selected tibia in eight growing pigs. The contralateral tibia was used as control. After 12 weeks, the pigs were killed and the tibiae harvested. The specimens were studied macroscopically and histology samples were obtained. Physeal morphology, thickness and characteristics were then described. RESULTS: Macroscopically, the articular cartilage was normal in all the treated tibiae. Microscopically, the physis was detected as a discontinuous line on the treated tibiae while it was continuous in all controls. In the control specimens, the mean thickness of the physis was 625 µm (606-639, SD = 14). All the physeal layers were organized. In the ablated specimens, disorganized layers in a heterogeneous line were observed. Bone bridges were identified at the ablation sites. The central part of the physis looked normal. Next to the bone bridge, the physis was thicker and presented fibrosis. The mean thickness was 820 µm (628-949, SD = 130). No abnormalities in the articular cartilage were observed. CONCLUSIONS: Thermal epiphysiodesis with RFA disrupts the physeal morphology and causes the formation of bone bridges at the ablation sites. This procedure does not damage the adjacent articular cartilage. The damaged tissue, next to the bone bridges, is characterized by disorganization and fibrosis.


Asunto(s)
Ablación por Catéter/métodos , Placa de Crecimiento/patología , Diferencia de Longitud de las Piernas/cirugía , Tibia/patología , Animales , Modelos Animales de Enfermedad , Femenino , Estudios de Seguimiento , Diferencia de Longitud de las Piernas/diagnóstico , Periodo Posoperatorio , Porcinos
6.
J Child Orthop ; 10(6): 471-477, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27826908

RESUMEN

In paediatric orthopaedics, deformities and discrepancies in length of bones are key problems that commonly need to be addressed in daily practice. An understanding of the physiology behind developing bones is crucial for planning treatment. Modulation of the growing bone can be performed in a number of ways. Here, we discuss the principles and mechanisms behind the techniques. Historically, the first procedures were destructive in their mechanism but reversible techniques were later developed with stapling of the growth plate being the gold standard treatment for decades. It has historically been used for both angular deformities and control of overall bone length. Today, tension band plating has partially overtaken stapling but this technique also carries a risk of complications. The diverging screws in these implants are probably mainly useful for hemiepiphysiodesis. We also discuss new minimally invasive techniques that may become important in future clinical practice.

7.
J Child Orthop ; 10(4): 359-64, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27278056

RESUMEN

PURPOSE: To test the hypothesis that epiphysiodesis made with radiofrequency ablation (RFA) is a safe procedure that disrupts the growth plate without damaging the adjacent joint articular cartilage. METHODS: RFA epiphysiodesis was done during 8 min in vivo in 40 growing pig tibia physis. In addition, three tibiae were ablated for 16 min and three more for 24 min. As a burned cartilage reference, six tibiae were ablated on the joint articular cartilage for 8 min. After the procedure, the animals were terminated and the tibiae were harvested. Magnetic resonance imaging (MRI) was done ex vivo to evaluate the joint articular cartilage in all samples. We used T1-weighted, T2-weighted, and water content sequences under a 1.5 T magnetic field. RESULTS: On the burned articular cartilage, intensity changes were observed at MRI. We found no evidence of articular cartilage damage on the 40 8-min RFA procedures. The tibiae ablated for 16 min and 24 min showed intact joint cartilage. CONCLUSIONS: Epiphysiodesis using RFA is safe for the adjacent articular cartilage. This study shows that RFA can be done safely in the growing physis of pigs, even with triple duration procedures.

8.
Acta Orthop ; 85(5): 538-42, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25036720

RESUMEN

BACKGROUND AND PURPOSE: Current techniques for epiphysiodesis involve opening of cortical windows; use of staples, screws, and tension devices; and fusion with curettes or drills. Complications may have serious consequences. There is a need for a more reliable, precise, and less traumatic procedure that overcomes the known complications from existing techniques. We analyzed a new epiphysiodesis technique using radio-frequency ablation (RFA) in a porcine model. METHODS: Six 35-kg and two 25-kg immature pigs were used. 1 hind leg of each animal was randomly selected and the proximal tibia growth plate was ablated laterally and medially. The contralateral leg was used as a control. MR images were obtained immediately after the ablation and 12 weeks later for 6 animals, and 24 weeks later for the other 2 animals. CT was done for the 2 animals that were followed for 24 weeks for proof of bone bridges. RESULTS: Both tibias were equal in length initially. At the 12-week follow-up, there was an average leg length discrepancy of 3.9 mm (95% CI: 3.0-4.8), and at 24 weeks the difference was 8.4 mm and 7.5 mm. No damage to the adjacent tissue was found. Bone bridges and physeal closure were found after 24 weeks. The pigs showed no discomfort after the intervention. INTERPRETATION: We found RFA to be feasible for epiphysiodesis in a pig model. The method is minimally invasive and recovery may be quick compared to conventional methods. We recommend that the method should be tested in larger-scale safety studies before clinical application.


Asunto(s)
Diferencia de Longitud de las Piernas/cirugía , Radiocirugia/métodos , Técnicas de Ablación/métodos , Animales , Modelos Animales de Enfermedad , Epífisis/cirugía , Femenino , Placa de Crecimiento/cirugía , Imagen por Resonancia Magnética , Porcinos , Tibia/anatomía & histología , Tibia/cirugía
9.
Skeletal Radiol ; 43(9): 1263-9, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24946947

RESUMEN

PURPOSE: To analyze the accuracy of growth-plate thickness measurements detected on 1.5-T and 7-T MR images using histology sections as a standard of reference. MATERIALS AND METHODS: Four defrosted pig tibiae were 1.5-T MR scanned and one fresh tibia was 7-T MR scanned. The height of the growth plate was measured and compared to histology. RESULTS: Histology measurements showed a mean growth plate thickness of 467 µm (SD = 82.2). The mean growth plate thickness measured in the 7-T MR images was 465 µm (SD = 62.2) and 1,325 µm (SD = 183.5) on 1.5-T MR measurements. We found a better correspondence between the growth plate thickness measured on the 7-T MR and histology samples compared to 1.5 T. CONCLUSIONS: The growth plate can be identified and measured with high accuracy using 7-T MR. 1.5-T MR can only describe some morphological characteristics.


Asunto(s)
Placa de Crecimiento/anatomía & histología , Interpretación de Imagen Asistida por Computador/métodos , Imagen por Resonancia Magnética/métodos , Tibia/anatomía & histología , Animales , Técnicas In Vitro , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Porcinos
10.
Gac. méd. Méx ; 143(6): 477-481, nov.-dic. 2007. ilus, tab
Artículo en Español | LILACS | ID: lil-568585

RESUMEN

Introducción: Los programas de transplante de órganos de donador fallecido requieren una estructura compleja desde el punto de vista médico, logístico y cultural. Material y métodos: Se analizó la detección de posibles donadores en el estado de San Luis Potosí, del 21 de agosto de 1999 al 30 de agosto de 2002; se estudiaron las principales causas de muerte cerebral, su conversión a donadores, las implicaciones médicolegales y las causas de donación y no donación. Resultados: 71.42% de donadores y 64.15% de los no donadores tuvieron implicaciones médico-legales. La principal causa de muerte cerebral fue el traumatismo craneoencefálico (66.97%). La tasa de donantes por millón de habitantes fue de 8.3. Conclusiones: El manejo adecuado de los aspectos médico-legales influye en la tasa de donadores fallecidos lograda. Esto, aunado a la coordinación y efectividad del Consejo Estatal de Trasplantes, permitió obtener la tasa más alta de donación de este tipo en México.


INTRODUCTION: The transplantation program of organs obtained from deceased donors requires a complex structural organization. Medical, logistic, and cultural aspects must be taken into account. MATERIAL AND METHODS: We analyzed the detection of possible organ donors in San Luis Potosí, Mexico, from August 21, 1999 to August 30, 2002. We studied the main causes of brain death, donor conversion, legal implications, reasons for donation and refusal to donate. RESULTS: 71.42% of donors and 64.15% of non donors required legal intervention. The main cause of brain death was brain traumatic injury (66.97%). The donation rate per one million inhabitants was 8.3. CONCLUSIONS: Adequate forensic management has a positive influence on achieved deceased donors. An effective team work and coordination with the State Council of Transplants has allowed the State of San Luis Potosí to have the highest rate of organ donation in Mexico.


Asunto(s)
Humanos , Masculino , Femenino , Niño , Adolescente , Adulto , Persona de Mediana Edad , Muerte Encefálica , Obtención de Tejidos y Órganos , México , Muerte Encefálica/legislación & jurisprudencia , Obtención de Tejidos y Órganos/legislación & jurisprudencia , Estudios Retrospectivos
11.
Gac Med Mex ; 143(6): 477-81, 2007.
Artículo en Español | MEDLINE | ID: mdl-18269078

RESUMEN

INTRODUCTION: The transplantation program of organs obtained from deceased donors requires a complex structural organization. Medical, logistic, and cultural aspects must be taken into account. MATERIAL AND METHODS: We analyzed the detection of possible organ donors in San Luis Potosí, Mexico, from August 21, 1999 to August 30, 2002. We studied the main causes of brain death, donor conversion, legal implications, reasons for donation and refusal to donate. RESULTS: 71.42% of donors and 64.15% of non donors required legal intervention. The main cause of brain death was brain traumatic injury (66.97%). The donation rate per one million inhabitants was 8.3. CONCLUSIONS: Adequate forensic management has a positive influence on achieved deceased donors. An effective team work and coordination with the State Council of Transplants has allowed the State of San Luis Potosí to have the highest rate of organ donation in Mexico.


Asunto(s)
Muerte Encefálica , Obtención de Tejidos y Órganos , Adolescente , Adulto , Muerte Encefálica/legislación & jurisprudencia , Niño , Femenino , Humanos , Masculino , México , Persona de Mediana Edad , Estudios Retrospectivos , Obtención de Tejidos y Órganos/legislación & jurisprudencia
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