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1.
Inorg Chem ; 63(10): 4566-4573, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38407051

RESUMEN

This work presents a study on a new uranium iron arsenide UFe5As3. By implementing Bi-flux synthesis, we were able to grow mm-sized single crystals of this compound, which show twinning. UFe5As3 is one of only two known uranium iron arsenides. It adopts a monoclinic, UCr5P3-type crystal structure (space group P21/m, Pearson symbol mP18, a = 7.050(2) Å, b = 3.8582(9) Å, c = 9.634(1) Å, ß = 100.25(1)°). The magnetic susceptibility of UFe5As3 indicates it to be an antiferromagnet with TN = 47 K and µeff = 4.94 µB per formula unit, signaling that both U and Fe are likely magnetic in this material. The material appears to be anisotropic, with a small (likely ferromagnetic) spin reorientation transition around T = 29 K. The Sommerfeld coefficient γ0 = 135 mJ mol-1 K-2 suggests enhanced effective electron mass in UFe5As3, while electrical resistivity indicates metallic, Kondo-like behavior.

2.
Angew Chem Int Ed Engl ; 59(27): 11136-11141, 2020 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-32202036

RESUMEN

An efficient application of a material is only possible if we know its physical and chemical properties, which is frequently obstructed by the presence of micro- or macroscopic inclusions of secondary phases. While sometimes a sophisticated synthesis route can address this issue, often obtaining pure material is not possible. One example is TaGeIr, which has highly sample-dependent properties resulting from the presence of several impurity phases, which influence electronic transport in the material. The effect of these minority phases was avoided by manufacturing, with the help of focused-ion-beam, a µm-scale device containing only one phase-TaGeIr. This work provides evidence for intrinsic semiconducting behavior of TaGeIr and serves as an example of selective single-domain device manufacturing. This approach gives a unique access to the properties of compounds that cannot be synthesized in single-phase form, sparing costly and time-consuming synthesis efforts.

3.
Orthopade ; 48(1): 92-95, 2019 Jan.
Artículo en Alemán | MEDLINE | ID: mdl-30535765

RESUMEN

BACKGROUND: Coccygodynia is still often considered a mystery, and many patients are not taken seriously with their problems and pain. CASE: A 51-year-old thin lady presented at our clinic with lifelong, persistent low back pain. The clinical examination indicated suspicion of coccygodynia. A functional X­ray revealed a hypermobile os coccygeum with dorsal tilt. After a total coccygectomy via a y-shaped approach, she was completely pain free at the 12 months follow-up examination. No surgical site infection occurred in this period.


Asunto(s)
Dolor de la Región Lumbar , Dolor Musculoesquelético , Cóccix , Femenino , Humanos , Persona de Mediana Edad , Radiografía , Resultado del Tratamiento
4.
Z Rheumatol ; 77(8): 651-666, 2018 Oct.
Artículo en Alemán | MEDLINE | ID: mdl-30069740

RESUMEN

BACKGROUND: Taking part in physical education is an important element of social participation for children with chronic diseases. Nevertheless, children suffering from rheumatism mostly receive recommendations to stop sport activities either completely or partially, without underlying scientific guidelines. OBJECTIVE: The aim was the development of an IT-tool based on scientific data in order to create individualized recommendations for sport activities plus verification of its practical feasibility. MATERIAL AND METHODS: An interdisciplinary group of experts developed and approved a prototype of the rheumatism and sports compass (Rheuma und Sport Kompass, RSK) based on the literature and own experience. They considered individual health factors and biomechanics of sports functions. The prototype was tested, revised and reconsidered in an interim evaluation. The resulting RSKv1 was evaluated in a clinical observation phase with 61 patients. The results were subsequently incorporated into the final version of RSK during an interdisciplinary decision-making process. This was verified in a feasibility study with a follow-up survey of rheumatic patients with a RSK partial participation certification for physical education including: clinical assessment during 8 lessons of physical education and after 8 lessons of physical education. Teachers rated the RSK online after 8 lessons. The evaluation was descriptive and differences in mean values were tested. RESULTS AND DISCUSSION: In this study 50 patients and 31 teachers were evaluated. The affliction of pain decreased in terms of frequency, amount and duration after physical education with RSK. No worsening in health was reported after participation in sports. The teachers rated the RSK as understandable, practicable and they felt confident to allow the patients to participate in classes. The RSK was rated significantly better than a standard certification text. With the RSK, patients can be advised to safely take part in physical education.


Asunto(s)
Educación y Entrenamiento Físico , Enfermedades Reumáticas , Deportes , Certificación , Niño , Humanos , Examen Físico , Enfermedades Reumáticas/diagnóstico
5.
Phys Rev Lett ; 119(12): 126402, 2017 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-29341652

RESUMEN

A ferromagnetic quantum critical point is thought not to exist in two- and three-dimensional metallic systems yet is realized in the Kondo lattice compound YbNi_{4}(P,As)_{2}, possibly due to its one-dimensionality. It is crucial to investigate the dimensionality of the Fermi surface of YbNi_{4}P_{2} experimentally, but common probes such as angle-resolved photoemission spectroscopy and quantum oscillation measurements are lacking. Here, we study the magnetic-field dependence of transport and thermodynamic properties of YbNi_{4}P_{2}. The Kondo effect is continuously suppressed, and additionally we identify nine Lifshitz transitions between 0.4 and 18 T. We analyze the transport coefficients in detail and identify the type of Lifshitz transitions as neck or void type to gain information on the Fermi surface of YbNi_{4}P_{2}. The large number of Lifshitz transitions observed within this small energy window is unprecedented and results from the particular flat renormalized band structure with strong 4f-electron character shaped by the Kondo lattice effect.

6.
Eur Spine J ; 25(6): 1800-5, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26577394

RESUMEN

OBJECTIVE: To determine the presence of a consistent osseous corridor through S1 and S2 and fluoroscopic landmarks thereof, which could be used for safe trans ilio-sacroiliac screw fixation of posterior pelvic ring disorders. STUDY DESIGN: Computed tomography (CT) based anatomical investigation utilising multiplanar image and trajectory reconstruction (Agfa-IMPAX Version 5.2 software). Determination of the presence and dimension of a continuous osseous corridor in the coronal plane of the sacrum at the S1 and S2 vertebral levels. OUTCOME MEASURES: Determination of: (a) the presence of an osseous corridor in the coronal plane through S1 and S2 in males and females; (b) the dimension of the corridor with regard to diameter and length; (c) the fluoroscopic landmarks of the corridor. RESULTS: The mean cross-sectional area for S1 corridors in males and females was 2.13 and 1.47 cm(2) , respectively. The mean cross-sectional area for the S2 corridor in males and females was 1.46 and 1.13 cm(2), respectively. The limiting anatomical factor is the sagittal diameter of the sacral ala at the junction to the vertebral body. The centre of the S1 and S2 corridor is located in close proximity to the centre of the S1 and S2 vertebrae on the lateral fluoroscopic view as determined by the adjacent endplates and anterior and posterior vertebral cortices. CONCLUSION: Two-thirds of males and females have a complete osseous corridor to pass a trans-sacroiliac S1 screw of 8 mm diameter. The S2 corridor was present in all males but only in 87 % of females. Preoperative review of the axial CT slices at the midpoint of the S1 or S2 vertebral body allows the presence of a trans-sacroiliac osseous corridor to be determined by assessing the passage at the narrowest point of the corridor at the junction of the sacral ala to the vertebral body.


Asunto(s)
Tornillos Óseos , Fluoroscopía/métodos , Procedimientos Ortopédicos/métodos , Sacro , Adulto , Femenino , Humanos , Masculino , Sacro/anatomía & histología , Sacro/diagnóstico por imagen , Sacro/cirugía , Tomografía Computarizada por Rayos X
8.
Eur Spine J ; 24(4): 724-33, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24664426

RESUMEN

BACKGROUND: Minimal-invasive cement augmentation techniques gained popularity recently. Long-term studies, however, are still not available focusing on the effect of possible acceleration of intervertebral disc degeneration. MATERIALS AND METHODS: Fifteen patients (average age 67.1 ± 6.9 years, range 58-77; 10 female, 5 male) with acute or osteoporotic fractures were included in this study and MRI scans were performed before surgery and after a mean follow-up period of 15.2 months (range 8-27 months). Out of these patients, seven were available for a long-term MRI scan after a mean of 94.3 months (range 84-96 months). Disc degeneration and injuries were graded according to published Pfirrmann and Oner scales. RESULTS: A total of 43 intervertebral discs with moderate initial degeneration were examined pre-operatively and at the first follow-up. Twenty were available for the long-term-follow-up. At the first follow-up, 3 (1.3 %) discs showed a degenerative progression of 1 grade compared to the pre-operative MRI. Only one injured and one uninjured disc (0.4 %) showed progressive degeneration of 1 grade in the long-term follow up. No intervertebral disc in-between bisegmental cement augmentation showed acceleration of degenerative changes. CONCLUSION: Despite several limitations regarding patients' age and lack of performed perfusion MRI scans, this study suggests that vertebral cement augmentation through kyphoplasty has no significant influence on disc degeneration even after a long period. The absence of severe disc degeneration after vertebral augmentation supports further clinical trials, which should incorporate endplate perfusion studies for detailed information regarding disc perfusion.


Asunto(s)
Degeneración del Disco Intervertebral/etiología , Cifoplastia/efectos adversos , Fracturas Osteoporóticas/cirugía , Fracturas de la Columna Vertebral/cirugía , Anciano , Cementación/efectos adversos , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Fracturas por Compresión/cirugía , Humanos , Degeneración del Disco Intervertebral/diagnóstico , Desplazamiento del Disco Intervertebral , Estudios Longitudinales , Vértebras Lumbares/cirugía , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Vértebras Torácicas/cirugía
9.
Unfallchirurg ; 118(3): 233-9, 2015 Mar.
Artículo en Alemán | MEDLINE | ID: mdl-25783692

RESUMEN

The influence of the transport mode, i.e. Helicopter Emergency Medical Service (HEMS) versus ground-based Emergency Medical Service (EMS) on the mortality of multiple trauma patients is still controversially discussed in the literature. In this study a total of 333 multiple trauma patients treated over a 1-year period in a level I trauma center in Switzerland were analyzed. Using the newly established revised injury severity classification (RISC) score there was a tendency towards a better outcome for patients transported by HEMS (standardized mortality ratio 1.06 for HEMS versus 1.29 for EMS). Overall a short preclinical time and the presence of an emergency physician (EP) were associated with a better outcome.


Asunto(s)
Ambulancias Aéreas/estadística & datos numéricos , Automóviles/estadística & datos numéricos , Puntaje de Gravedad del Traumatismo , Traumatismo Múltiple/mortalidad , Traumatismo Múltiple/terapia , Centros Traumatológicos/estadística & datos numéricos , Servicios Médicos de Urgencia/estadística & datos numéricos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Traumatismo Múltiple/diagnóstico , Programas Nacionales de Salud/estadística & datos numéricos , Evaluación de Resultado en la Atención de Salud , Prevalencia , Factores de Riesgo , Tasa de Supervivencia , Suiza
11.
Eur Spine J ; 23(11): 2265-71, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24633718

RESUMEN

INTRODUCTION: The thoracolumbar junction (TJ) is traditionally exposed by lateral or posterior approaches. This usually requires splitting of the diaphragm, or extensile removal of the posterior elements. A circumferential exposure (i.e. simultaneous anterior and bilateral exposure) of the vertebral body is not possible. Direct anterior access would allow circumferential exposure of the vertebral body, with adjacent disc levels, and would avoid splitting the diaphragm or extensive removal of the posterior bony structures. MATERIALS AND METHODS: Twelve Thiel cadavers (8 f/4 m) were dissected to access T12 or L1 via a midline laparotomy. Supra- and infragastric laparatomy techniques were investigated. Six cadavers were used to reach T12 through the lesser omentum, six to reach L1 through the greater omentum. RESULTS: T12 after bluntly dissecting the lesser omentum, the lesser gastric curvature and the caudate lobe of the liver were utilised as landmarks. A small retroperitoneal incision was performed to mobilise the aorta allowing exposure of the T12 vertebra and its adjacent discs. Discectomy, corpectomy and insertion of an anterior column support were possible. The L1 level can be reached through the greater omentum by mobilising the pancreas as a single retroperitoneal structure, leaving the aorta and celiac trunk as landmarks. Retraction of the great vessels is necessary to expose L1 with its adjacent discs. Implantation of an anterior column support was possible utilising this approach. CONCLUSION: Direct anterior access to the TJ is feasible in a reproducible manner. This approach would avoid splitting the diaphragm, or dissection of the erector spinae muscles, and is likely to be less invasive than standard lateral or posterior approaches. This technique may offer a significant time reduction to surgery, especially in exposing the spine. Anterior column support can easily be performed, offering a better avoidance of kyphotic deformities.


Asunto(s)
Vértebras Lumbares/cirugía , Procedimientos Ortopédicos/métodos , Vértebras Torácicas/cirugía , Anciano , Anciano de 80 o más Años , Cadáver , Estudios de Factibilidad , Femenino , Humanos , Vértebras Lumbares/anatomía & histología , Masculino , Epiplón/cirugía , Vértebras Torácicas/anatomía & histología
12.
Klin Padiatr ; 226(6-7): 338-43, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25431866

RESUMEN

BACKGROUND: Recently, the UK CCLG and COG reported that an intrachromosomal amplification of chromosome 21 (iAMP21) in acute lymphoblastic leukemia (ALL) loses its adverse prognostic impact with intensified therapy. PATIENT AND METHODS: We evaluated the prognosis of iAMP21 among patients from the ALL-BFM (Berlin-Frankfurt-Münster) 2000 trial with 46 of 2 637 (2%) patients iAMP21+. RESULTS: 8-year event-free-survival (EFS, 64 ± 8% vs. 81 ± 1%, p=0.0026) and cumulative incidence of relapse (CIR, 29 ± 8% vs. 14 ± 1%, p=0.008) of the iAMP21 cases were significantly worse compared with non-iAMP21 patients. Within the MRD low-risk group, iAMP21 cases (n=14) had an inferior 8-year EFS (76 ± 12% vs. 92 ± 1%, p=0.0081), but no increased CIR (10 ± 10% vs. 6 ± 1%, p=0.624). Within the MRD intermediate-risk group, iAMP21 cases (n=27) had a worse 8-year EFS (56 ± 11% vs. 78 ± 2%, p=0.0077) and CIR (44 ± 11% vs. 20 ± 2%, p=0.003) with 6/10 relapses occurring after 2 years. CONCLUSIONS: Conclusively, we believe that there is no necessity for enrolling all iAMP21 patients into the high-risk arm of ongoing ALL-BFM trials because MRD low-risk patients have a moderate relapse risk under current therapy. Whether the increased relapse risk in MRD intermediate-risk patients can be avoided by late treatment intensification remains to be answered by the AIEOP-BFM ALL 2009 trial randomly using protracted pegylated L-asparaginase during delayed intensification and early maintenance.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Cromosomas Humanos Par 21/genética , Amplificación de Genes/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/tratamiento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Adolescente , Niño , Preescolar , Estudios de Cohortes , Subunidad alfa 2 del Factor de Unión al Sitio Principal/genética , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Neoplasia Residual/tratamiento farmacológico , Neoplasia Residual/genética , Neoplasia Residual/mortalidad , Leucemia-Linfoma Linfoblástico de Células Precursoras B/mortalidad , Proteínas Proto-Oncogénicas c-ets/genética , Recurrencia , Proteínas Represoras/genética , Proteína ETS de Variante de Translocación 6
13.
Eur Spine J ; 22(1): 21-5, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22382724

RESUMEN

INTRODUCTION: Odontoid fractures are the most common upper cervical spine fracture. There are two mechanisms in which odontoid fractures occur, most commonly hyperflexion of the neck resulting in displacement of the dens anteriorly and hyperextension resulting in posterior dens displacement. Type 2 fractures are the most common and are associated with significant non-union rates after treatment. One possible consequence of an odontoid fracture is a synovial cyst, resulting in spinal cord compression, presenting as myelopathy or radiculopathy. Synovial cysts as a result of spinal fracture, usually of the facet joint, are most common in the lumbar region, followed by the thoracic and then cervical region; cervical cysts are rare. Fracture and subsequent cyst formation is thought to be related to hyper-motion or trauma of the spine. This is reinforced by the appearance of spinal synovial cysts most commonly at the level of L4/5; this being the region with the biggest weight-bearing function. The most common site of cervical cyst formation is at the level of C7/T1; this is a transitional joint subjected to unique stress and mechanical forces not present at higher levels. Treatment of a cervical synovial cyst at the level of the odontoid is challenging with little information available in the literature. The majority of cases appear to implement posterior surgical resection of the cyst, with fusion of adjacent cervical vertebrae to stabilise the fracture, resulting in restricted range of movement. CASE PRESENTATION: We describe a case concerning a 39-year-old female who presented with uncertain cause of odontoid fracture, resulting in a cystic lesion compressing the upper cervical spinal cord. OUTCOME: Minimal invasive surgery of C1/C2 transarticular fusion was successfully performed resulting in significant improvement of neurological symptoms in this patient. At 1-year follow-up, the cyst had resolved without surgical removal and this was confirmed by radiological measures.


Asunto(s)
Apófisis Odontoides/lesiones , Fracturas de la Columna Vertebral/cirugía , Fusión Vertebral/métodos , Quiste Sinovial/cirugía , Adulto , Femenino , Humanos , Apófisis Odontoides/cirugía , Fracturas de la Columna Vertebral/complicaciones , Quiste Sinovial/complicaciones
14.
Eur Spine J ; 22(12): 2876-83, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24043336

RESUMEN

BACKGROUND: Iatrogenic spondylolisthesis is a challenging condition for spinal surgeons. Posterior surgery in these cases is complicated by poor anatomical landmarks, scar tissue adhesion of muscle and dural structures and difficult access to the intervertebral disc. Anterior interbody fusion provides an alternative treatment method, allowing indirect foraminal decompression, reliable disc clearance and implantation of large surface area implants. MATERIALS AND METHODS: A retrospective chart review of patients with iatrogenic spondylolisthesis including pre- and post-operative Oswestry Disability Index (ODI) and Visual Analogue Scale (VAS) scores was performed. Imaging criteria were pelvic incidence, overall lumbar lordosis and segmental lordosis. In addition, the fusion rate was investigated after 6 months. RESULTS: Six consecutive patients treated between 2008 and 2011 (4 female, 2 male, mean age 61 ± 7.1 years) were identified. The initially performed surgeries included decompression with or without discectomy; posterior instrumented and non-instrumented fusion. The olisthetic level was in all cases at the decompressed level. All patients were revised with stand-alone anterior interbody fusion devices at the olisthetic level filled with BMP 2. Average ODI dropped from 49 ± 11 % pre-operatively to 26.0 ± 4.0 at 24 months follow-up. VAS average dropped from 7 ± 1 to 2 ± 0. Mean total lordosis of 39.8 ± 2.8° increased to 48.5 ± 4.9° at pelvic incidences of 48.8 ± 6.8° pre-operatively. Mean segmental lordosis at L4/5 improved from 10.5 ± 6.7° to 19.0 ± 4.9° at 24 months. Mean segmental lordosis in L5/S1 increased from 15.1 ± 7.4° to 23.2 ± 5.6°. Cage subsidence due to severe osteoporosis occurred in one case after 5 months, and hence there was no further follow-up. Fusion was confirmed in all other patients. CONCLUSION: Anterior interbody fusion offers good stabilisation and restoration of lordosis in iatrogenic spondylolisthesis and avoids the well-known problems associated with reentering the spinal canal for revision fusions. In this group, ODI and VAS scores were improved.


Asunto(s)
Enfermedad Iatrogénica , Vértebras Lumbares/cirugía , Prótesis e Implantes , Terapia Recuperativa/métodos , Fusión Vertebral/métodos , Espondilolistesis/cirugía , Anciano , Proteína Morfogenética Ósea 2/administración & dosificación , Descompresión Quirúrgica/efectos adversos , Femenino , Estudios de Seguimiento , Migración de Cuerpo Extraño/etiología , Humanos , Lordosis/etiología , Lordosis/cirugía , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/patología , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Dolor Postoperatorio/diagnóstico , Dolor Postoperatorio/etiología , Periodo Posoperatorio , Prótesis e Implantes/efectos adversos , Reoperación , Estudios Retrospectivos , Fusión Vertebral/efectos adversos , Fusión Vertebral/instrumentación , Espondilolistesis/diagnóstico , Espondilolistesis/etiología , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
15.
Eur Spine J ; 22 Suppl 1: S16-20, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23250515

RESUMEN

PURPOSE: Anterior lumbar surgery is a common procedure for anterior lumbar interbody fusion (ALIF) and artificial disc replacement (ADR). Our aim was to study the exposure related complications for anterior lumbar spinal surgery performed by spinal surgeons. METHODS: A retrospective review was performed for 304 consecutive patients who underwent anterior lumbar spinal surgery over 10 years (2001-2010) at our institution. Each patient's records were reviewed for patients' demographics, diagnosis, level(s) of surgery, procedure and complications related to access surgery. Patients undergoing anterior lumbar access for tumour resection, infection, trauma and revision surgeries were excluded. RESULTS: All patients underwent an anterior paramedian retroperitoneal approach from the left side. The mean age of patients was 43 years (10-73; 197 males, 107 females). Indications for surgery were degenerative disc disease (DDD 255), degenerative spondylolisthesis (23), scoliosis (18), iatrogenic spondylolisthesis (5) and pseudoarthrosis (3). The procedures performed were single level surgery--L5/S1 (n = 147), L4/5 (n = 62), L3/4 (n = 7); two levels--L4/5 and L5/S1 (n = 74), L3/4 and L4/5 (n = 4); three levels--L3/4, L4/5, L5/S1 (n = 5); four levels--L2/3, L3/4, L4/5, L5/S1 (n = 5). The operative procedures were single level ADR (n = 131), a single level ALIF (n = 87) with or without posterior fusion, two levels ALIF (n = 54), two levels ADR (n = 14), a combination of ADR/ALIF (n = 10), three levels ALIF (n = 1), three levels ADR/ALIF/ALIF (n = 1), ADR/ADR/ALIF (n = 2), four levels ALIF (n = 1) and finally 3 patients underwent a four level ADR/ADR/ALIF/ALIF. The overall complication rate was 61/304 (20 %). This included major complications (6.2 %)--venous injury requiring suture repair (n = 14, 4.6 %) and arterial injury (n = 5 [1.6 %], 3 repaired, 2 thrombolysed). Minor complications (13.8 %) included venous injury managed without repair (n = 5, 1.6 %), infection (n = 13, 4.3 %), incidental peritoneal opening (n = 12, 3.9 %), leg oedema (n = 2, 0.6 %) and others (n = 10, 3.3 %). We had no cases of retrograde ejaculation. CONCLUSION: We report a very thorough and critical review of our anterior lumbar access surgeries performed mostly for DDD and spondylolisthesis at L4/5 and L5/S1 levels. Vascular problems of any type (24/304, 7.8 %) were the most common complication during this approach. The incidence of major venous injury requiring repair was 14/304 (4.6 %) and arterial injury 5/304 (1.6 %). The requirement for a vascular surgeon with the vascular injury was 9/304 (3 %; 5 arterial injuries; 4 venous injuries). This also suggests that the majority of the major venous injuries were repaired by the spinal surgeon (10/14, 71 %). Our results are comparable to other studies and support the notion that anterior access surgery to the lumbar spine can be performed safely by spinal surgeons. With adequate training, spinal surgeons are capable of performing this approach without direct vascular support, but they should be available if required.


Asunto(s)
Vértebras Lumbares/cirugía , Procedimientos Ortopédicos/efectos adversos , Lesiones del Sistema Vascular/etiología , Adolescente , Adulto , Anciano , Niño , Femenino , Humanos , Degeneración del Disco Intervertebral/cirugía , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Escoliosis/cirugía , Espondilolistesis/cirugía , Adulto Joven
16.
Eur Spine J ; 21(3): 390-5, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22008862

RESUMEN

Progressive high-grade spondylolisthesis can lead to spinal imbalance. High-grade spondylolisthesis is often reduced and fused in unbalanced pelvises, whereas in-situ fusion is used more often in balanced patients. The surgical goal is to recreate or maintain sagittal balance but if anatomical reduction is necessary, the risk of nerval damage with nerve root disruption in worst cases is increased. Spinal dysraphism like spina bifida or tethered cord syndrome make it very difficult to achieve reduction and posterior fusion due to altered anatomy putting the focus on anterior column support. Intensive neural structure manipulation should be avoided to reduce neurological complications and re-tethering in these cases. A 26-year-old patient with a history of diastematomyelia, occult spina bifida and tethered cord syndrome presented with new onset of severe low back pain, and bilateral L5/S1 sciatica after a fall. The X-ray demonstrated a grade III spondylolisthesis with spina bifida and the MRI scan revealed bilateral severely narrowed exit foramina L5 due to the listhesis. Because she was well balanced sagittally, the decision for in-situ fusion was made to minimise the risk of neurological disturbance through reduction. Anterior fusion was favoured to minimise manipulation of the dysraphic neural structures. Fusion was achieved via isolated access to the L4/L5 disc space. A L5 transvertebral hollow modular anchorage (HMA) screw was passed into the sacrum from the L4/L5 disc space and interbody fusion of L4/L5 was performed with a cage. The construct was augmented with pedicle screw fixation L4-S1 via a less invasive bilateral muscle split for better anterior biomechanical support. The postoperative course was uneventful and fusion was CT confirmed at the 6-month follow-up. At the last follow-up, she worked full time, was completely pain free and not limited in her free-time activities. The simultaneous presence of high-grade spondylolisthesis and spinal dysraphism make it very difficult to find a decisive treatment plan because both posterior and anterior treatment strategies have advantages and disadvantages in these challenging cases. The described technique combines several surgical options to achieve 360° fusion with limited access, reducing the risk of neurological sequelae.


Asunto(s)
Vértebras Lumbares/cirugía , Radiculopatía/cirugía , Disrafia Espinal/cirugía , Fusión Vertebral/instrumentación , Fusión Vertebral/métodos , Espondilolistesis/cirugía , Adulto , Femenino , Humanos , Vértebras Lumbares/anomalías , Vértebras Lumbares/diagnóstico por imagen , Radiculopatía/etiología , Radiculopatía/fisiopatología , Radiografía , Disrafia Espinal/complicaciones , Disrafia Espinal/diagnóstico , Espondilolistesis/complicaciones , Espondilolistesis/diagnóstico
17.
Eur Spine J ; 21(5): 829-36, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22189695

RESUMEN

PURPOSE: U-shaped sacral fractures usually result from axial loading of the spine with simultaneous sacral pivoting due to a horizontal fracture which leads to a highly unstable spino-pelvic dissociation. Due to the rarity of these fractures, there is lack of an agreed treatment strategy. METHODS: A thorough literature search was carried out to identify current treatment concepts. The studies were analysed for mechanism of injury, diagnostic imaging, associated injuries, type of surgery, follow-up times, complications, neurological, clinical and radiological outcome. RESULTS: Sixty-three cases were found in 12 articles. No Class I, II or III evidence was found in the literature. The most common mechanism of injury was a fall or jump from height. Pre-operative neurological deficit was noted in 50 (94.3%) out of 53 cases (not available in 10 patients). The most used surgical options were spino-pelvic fixation with or without decompression and ilio-sacral screws. Post-operative complications occurred in 24 (38.1%) patients. Average follow-up time was 18.6 months (range 2-34 months). Full neurological recovery was noted in 20 cases, partial recovery in 14 and 9 patients had no neurological recovery (5 patients were lost in follow-up). Fracture healing was mentioned in 7 articles with only 1 case of fracture reduction loss. CONCLUSION: From the current available data, an evidence based treatment strategy regarding outcome, neurological recovery or fracture healing could not be identified. Limited access and minimal-invasive surgery focussing on sacral reduction and restoration seems to offer comparable results to large spino-pelvic constructs with fewer complications and should be considered as the method of choice. If the fracture is highly unstable and displaced, spino-pelvic fixation might offer better stability.


Asunto(s)
Fracturas Óseas/cirugía , Procedimientos Ortopédicos/instrumentación , Procedimientos Ortopédicos/métodos , Sacro/lesiones , Adolescente , Adulto , Tornillos Óseos , Niño , Femenino , Curación de Fractura , Humanos , Fijadores Internos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Adulto Joven
18.
Dev Biol (Basel) ; 134: 93-100, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22888600

RESUMEN

Vaccines play a key role in the control of viral diseases both in humans and in animals. In order to ensure the quality and consistency of vaccines they are extensively tested, including potency control of individual batches. In the case of vaccines against rabies the most widely used test for batch potency control is the National Institutes of Health (NIH) test. The NIH test is performed in mice leading to the consumption of thousands of animals every year. Protection against rabies after vaccination is associated with neutralizing antibodies directed against the viral glycoprotein (G). Therefore the amount of G-protein in vaccine preparations is an important parameter with regard to potency. Additionally the structural integrity of virus particles in vaccine preparations may be crucial for their immunogenicity. The objective of our work is the development of in vitro methods to determine the potency of vaccines against rabies. The result of this ongoing project shall be an assay panel including measurement of the antigenic content as well as parameters of antigen quality in a vaccine preparation allowing a precise prediction of the potency of rabies vaccines without using animal experiments.


Asunto(s)
Vacunas Antirrábicas/inmunología , Virus de la Rabia/inmunología , Rabia/inmunología , Vacunación/métodos , Animales , Antígenos Virales/inmunología , Línea Celular , Ensayo de Inmunoadsorción Enzimática , Ratones , Microscopía Electrónica , Proteínas de la Nucleocápside/inmunología , Rabia/prevención & control , Vacunas Antirrábicas/administración & dosificación , Virus de la Rabia/ultraestructura
19.
Z Rheumatol ; 71(5): 387-95, 2012 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-22732914

RESUMEN

Control of disease activity and recovery of function are major issues in the treatment of children and adolescents suffering from juvenile idiopathic arthritis (JIA). Functional therapies including physiotherapy are important components in the multidisciplinary teamwork and each phase of the disease requires different strategies. While in the active phase of the disease pain alleviation is the main focus, the inactive phase requires strategies for improving motility and function. During remission the aim is to regain general fitness by sports activities. These phase adapted strategies must be individually designed and usually require a combination of different measures including physiotherapy, occupational therapy, massage as well as other physical procedures and sport therapy. There are only few controlled studies investigating the effectiveness of physical therapies in JIA and many strategies are derived from long-standing experience. New results from physiology and sport sciences have contributed to the development in recent years. This report summarizes the basics and main strategies of physical therapy in JIA.


Asunto(s)
Artritis Juvenil/rehabilitación , Modalidades de Fisioterapia/tendencias , Medicina Física y Rehabilitación/tendencias , Enfermedades Reumáticas/rehabilitación , Reumatología/tendencias , Adolescente , Niño , Preescolar , Humanos , Masculino
20.
Sci Rep ; 12(1): 21901, 2022 12 19.
Artículo en Inglés | MEDLINE | ID: mdl-36535994

RESUMEN

This study investigated transfer of improvements in stability recovery performance to novel perturbations. Thirty adults (20-53 yr) were assigned equally to three treadmill walking groups: groups exposed to eight trip perturbations of either low or high magnitude and a third control group that walked unperturbed. Following treadmill walking, participants were exposed to stability loss from a forward-inclined position (lean-and-release) and an overground trip. Lower limb joint kinematics for the swing phase of recovery steps was compared for the three tasks using statistical parametric mapping and recovery performance was analysed by margin of stability and base of support. The perturbation groups improved stability (greater margin of stability) over the eight gait perturbations. There was no group effect for stability recovery in lean-and-release. For the overground trip, both perturbation groups showed similar enhanced stability recovery (margin of stability and base of support) compared to controls. Differences in joint angle kinematics between treadmill-perturbation and lean-and-release were more prolonged and greater than between the two gait perturbation tasks. This study indicates that: (i) practising stability control enhances human resilience to novel perturbations; (ii) enhancement is not necessarily dependent on perturbation magnitude; (iii) differences in motor response patterns between tasks may limit transfer.


Asunto(s)
Equilibrio Postural , Caminata , Adulto , Humanos , Equilibrio Postural/fisiología , Caminata/fisiología , Marcha/fisiología , Fenómenos Biomecánicos , Prueba de Esfuerzo
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