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Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Akteure der öffentlichen Gesundheit (Public Health) tragen wesentlich zu Gesundheitsschutz, -förderung und...  相似文献   
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Background Context

The concept of dynamic stabilization (DS) of the lumbar spine for treatment of degenerative instability has been introduced almost two decades ago. Dynamic stabilization follows the principle of controlling movement in the coronal plane by providing load transfer of the spinal segment without fusion and, at the same time, reducing side effects such as adjacent segment disease (ASD). So far, only little is known about revision rates after DS due to ASD and screw loosening (SL).

Purpose

The present study aimed to evaluate the longitudinal revision rates following dynamic pedicle screw stabilization in the lumbar spine and to determine specific risk factors predictive for ASD, SL, and overall reoperation in a large cohort with considerable follow-up.

Design

We carried out a post hoc analysis of a prospectively collected database in a level I spine center.

Patients Example

The patient sample comprised 283 (151 female/132 male) consecutive patients suffering from painful degenerative lumbar segmental instability with or without spinal stenosis who underwent DS of the lumbar spine (Ulrich Cosmic, Ulrich Medical, Ulm, Germany) between January 2008 and December 2011.

Outcome Measures

Longitudinal reoperation rate and risk factors predictive for revision surgery were evaluated.

Methods

We analyzed the longitudinal reoperation rate due to ASD and SL and overall reoperation. Risk factors such as age, gender, body mass index, lumbar lordosis (LL), number of segments, and number of previous surgeries were taken into account. Regular and mixed model logistic regressions were performed to determine risk factors for revision surgery on a patient and on a screw level.

Results

The mean age was 65.7±10.2 years (range 31–88). One hundred thirty-two patients were stabilized in 1 segment, 134 in 2 segments, 15 in 3 segments, and 2 patients in 4 segments. Reoperation rate for ASD and SL after 1 year was 7.4 %, after 2 years was 15.0%, and after a mean follow-up of 51.4±15 months was 22.6%. Reasons for revision were SL in 19 cases (6.6%), ASD in 39 cases (13.7%), SL and ASD in 6 cases, hematoma in 2 cases (0.7%), cerebrospinal fluid fistulae in 3 cases (1.1%), infection in 6 cases (2.1%), and implant failure in 1 case (0.4%). The patients' age, the number of stabilized segments, and the number of previous surgeries and postoperative LL had a significant influence on the probability for revision surgery.

Conclusions

Reoperation rates after DS of the lumbar spine are comparable with rigid fixations. The younger the patient and the more segments are involved, the lower the LL and the more previous surgeries were found, the higher was the risk of revision. Risk of revision was almost twice as high in men compared with women. We therefore conclude that for clear clinical indication and careful evaluation of preoperative imaging data, DS using the Cosmic system seems to be a possible option. The presented data will help to further tailor indication and patient selection.  相似文献   
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A novel assay for factor XIII is described that utilizes exclusively small synthetic peptides as substrates for the cross-linking reaction catalyzed by activated factor XIII (FXIIIa). The acyl donor substrate (selection peptide) is immobilized on a microplate via biotin while the acyl acceptor substrate (detection peptide) is labeled with the fluorochrome Oregon green to allow sensitive detection without the need for secondary enzyme systems for signal amplification. Starting with an amino acid sequence from the fibrin gamma-chain (GQQHHLGGAKQAGDV) as a prototype peptide, the influence of amino acid exchanges were investigated with respect to their impact on the FXIIIa-catalyzed reaction. It was found that FXIIIa readily accepts a broad range of substrate peptides, with a proline neighboring the essential lysine having the most detrimental effect. The assay appears to be valuable for the molecular characterization of factor XIII and may be used for a deeper investigation into the substrate requirements of this final enzyme of wound repair, and eventually also for the characterization of other transglutaminases.  相似文献   
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Zusammenfassung Über ein Jahr wurden 1082 allgemeinchirurgische Planeingriffe prospektiv konsekutiv erfaßt und ihre Komplikationen mit einem Score bewertet. EinflußgröBen und die Komplikationsraten, die unter Umständen von der Kliniks-organisation abhängig sind, sollten analysiert werden. Es fand sich eine Beziehung zwischen Komplikationen und Wochentag, Operationsdauer sowie der Abweichung der tatsächlich benötigten von der geplanten Operationszeit. Mit höherer Auslastung der Operationssäle pro Arbeitstag stiegen die Komplikationsraten ebenfalls an.Keinen Einfluß auf die Komplikationsraten hatten Operationsbeginn und-monat sowie die monatliche Auslastung der Säle. Ob das Wetter einen Einfluß auf die Komplikationsraten nahm, konnte nicht entschieden werden: so fanden sich im Sommer- höhere Komplikationsraten als im Winterhalbjahr, jedoch war der Score von der Höhe der Außentemperatur und der Luftfeuchtigkeit unabhängig.
The influence of time of operation and hospital organization on postoperative complication rates
Summary During a 1-year period 1082 general surgical interventions were prospectively documented and their complication rates evaluated by a score system. Factors responsible for the complication rates and possibly depending on hospital organization should be analysed. The complication rates were influenced by the selection of the weekday, the length of operation time and the extent of discrepancy between planned and required operation time. Furthermore, the complication rates paralleled the extent of utilization of the operation theatre during a workday. The complication rates werenot affected by the beginning of operation and the operation month as well as the monthly utilization of the operation theatres. Whether the weather did influence the complication rates could not be decided: higher complication rates were found in the summer as compared to the winter period, but the complication score was independent of the level of the outside temperature and humidity.
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The heavy metal bismuth induces a new type of selective neuronal degeneration that shares some common aspects with that seen following hypoxia and ischemia. Continuous application of 3 μm bismuth to organotypic cultures of rat hippocampus resulted after 2–3 weeks in selective degeneration of CA1 pyramidal cells, while CA3 pyramidal cells, dentate granule cells, and subicular neurons were resistant. With 10 μm MK-801, a noncompetitive NMDA-antagonist, during the entire culturing period failed to prevent neuronal degeneration induced by 3 μm bismuth. GABA-immunoreactive interneurons were also affected by bismuth, but were generally less sensitive than CA1 pyramidal cells. Acute application of up to 100 μm bismuth did not change the electrophysiological properties of CA1 pyramidal cells. © 1994 Wiley-Liss, Inc.  相似文献   
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The radiographic and histological morphology of 38 tumors lesions of the scapula are analyzed. Osteochondromas (n = 12), chondrosarcomas (n = 7), plasmacytomas (n = 4) and Ewing's sarcomas (n = 3) were the most frequent neoplasms. The radiographically determined growth rates allowed an estimate of the dignity in all cases. Benign lesions were only observed in the first five decades of life, and were mostly located in the scapular blade. Most tumors found in the acromion and in the glenoid region and all lesions diagnosed in the 6th to the 8th decades of life were malignant. In 63.2% of cases correct diagnosis of the type of lesion present was possible on radiographic examination.  相似文献   
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