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1.
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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Minimal inhibitory concentrations (MICs) of the oral cephalosporin BAY v 3522, and of cephprozyl, cefaclor, cefixime, cefuroxime, cefetamet, cefpodoxime and cefotaxime were determined against Gram-positive and Gram-negative clinical isolates with the NCCLS agar dilution procedures. BAY was the most active drug against Gram-positive organisms. MICs ranged from 0.01 mg/l against group A streptococci to 16 mg/l against S. faecium. Although mean MICs of BAY against methicillin-resistant S. aureus and S. epidermidis were between 0.9-1.8 mg/l, respectively, such strains showed typical heteroresistance in population studies. In addition, the biochemical correlate of methicillin-resistance, the PBP-2', showed similar low affinity to BAY as methicillin. beta-lactamase-producing H. influenzae and B. catarrhalis were inhibited by 2-8 and 0.25-2 mg/l, respectively, whereas non-producers were inhibited by 0.25-2 and 0.12-1 mg/l of the drug. The activity of BAY against enterobacteriaceae was rather low. Ampicillin-susceptible E. coli strains were inhibited by 2-8 and resistant strains by 8-32 mg/l. The mean MIC against cephalothin-susceptible K. pneumoniae strains was 2.8, and that against resistant strains 27.4 mg/l. MICs against beta-lactamase-producing enterobacteriaceae determined in broth dilution were 4-8 times higher than those determined in agar dilution. Bactericidal activity was measured in killing-curve experiments at 4 times the MIC. BAY killed equally well as standard control drugs.  相似文献   
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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 requirements for an efficient regionalization of high risk obstetrics include, among other things, a combination of out- and inpatient obstetricians, advice for pregnant woman provided in the antenatal care guidelines on the choice of the maternity hospital, and the acceptance of the gynecologist’s advice on the part of the pregnant woman with or without a high risk factor. The advice given in the antenatal care unit and the choice of maternity hospital were investigated using a random sample survey of clientele of a health insurance company. Some 20% of pregnant women with high risk did not receive a recommendation for a particular obstetrical unit. In approximately two thirds of all pregnant women, the choice of maternity hospital was not mentioned. Thus, the influence of the gynecologist on the choice of hospital was low.  相似文献   
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The most common functional disturbance of the elbow joint is the so called epicondylopathia humeri radialis. Nowadays, the favoured pathogenic model explains the pain by a hyperalgesia in the area of the wrist and the finger extensor springs on the radial epicondyle. The therapeutic concept includes pain control, passive stretching of the flexors, load free reactivation of the extensors and, after successful muscular rebalancing, a trainings program for the extensors. In order to carry out this staged therapy program, it is sometimes useful to exclude the nocigenerators on the epicondyle. This can be achieved by the local injection of 1% lidocaine 2 ml and 20 mg triamcinolone crystal suspension into the point of maximum pain. The techniques used for the injection in individual symptomatic regions of the elbow are described in detail.  相似文献   
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