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131.

Introduction

Surgery for lumbar spinal stenosis (LSS) is today the most frequently performed procedure in the adult lumbar spine. Long-term benefit of surgery for LSS is well documented both in randomized and in non-randomized trials. In this paper, we present the results from laminarthrectomy as an alternative surgical approach, which have theoretical advantages over other approaches. In this study, we wanted to study the clinical and radiological results of laminarthrectomy. Dural sac cross-sectional areal (DSCSA) is an objective method to quantify the degree of central stenosis in the spinal canal, and was used to measure whether we were able to achieve an adequate decompression of the spinal canal with laminarthrectomy as a surgical approach.

Materials and methods

All patients operated on with this approach consecutively in the period 1 January 2008 to 31 March 2009 were included in the study. All perioperative complications were noted. Clinical results were measured by means of a questionnaire. The patients that agreed to attend the study had an MRI taken of the operated level. DSCSA before and after surgery of the actual level were measured by three observers. We then performed a correlation test between increase of area and clinical results. We also tested for inter- and intra-observer reability.

Results

Fifty-six laminarthrectomy were performed. There were 17 % complications, none of them were life-threatening or disabling. 46 patients attended the study and answered the questionnaire. Thirty-four patients (83 %) reported clinical improvement, whereas six (13 %) patients reported no improvement, and two (4 %) patients reported that they were worse. Mean ODI was 23.0. Mean EQ-5D was 0.77. Mean VAS-score for back-pain was 3.1 and mean VAS-score for leg-pain was 2.8. Mean DSCSA were measured to 80 mm2 before surgery and 161 mm2 after surgery. That gave an increase of DSCSA of 81 mm2 (101 %). We found a significant positive correlation between increase of area and clinical results. We also found consistent inter- and intra-observer reability.

Discussion

In this study, the clinical results of laminarthrectomy were good, and comparable with other reports for LSS. The rates of complications are also comparable with other reports in spinal surgery. A significant increase in the spinal canal diameter was achieved. Within the limitations a retrospective study gives, we conclude that laminarthrectomy seems to be a safe and effective surgical approach for significant decompressing the adult central spinal canal, and measurement of DSCSA, before and after surgery seems to be a good way to quantify the degree of decompression.  相似文献   
132.

Introduction and hypothesis

Theoretically, tight or strong pelvic floor muscles may impair the progress of labor and lead to instrumental deliveries. We aimed to investigate whether vaginal resting pressure, pelvic floor muscle strength, or endurance at midpregnancy affect delivery outcome.

Methods

This was a prospective cohort study of women giving birth at a university hospital. Vaginal resting pressure, pelvic floor muscle strength, and endurance in 300 nulliparous pregnant women were assessed at mean gestational week 20.8 (±1.4) using a high precision pressure transducer connected to a vaginal balloon. Delivery outcome measures [acute cesarean section, prolonged second stage of labor (> 2 h), instrumental vaginal delivery (vacuum and forceps), episiotomy, and third- and fourth-degree perineal tear) were retrieved from the hospital’s electronic birth records.

Results

Twenty-three women were lost to follow-up, mostly because they gave birth at another hospital. Women with prolonged second stage had significantly higher resting pressure than women with second stage less than 2 h; the mean difference was 4.4 cmH2O [95 % confidence interval (CI) 1.2–7.6], p?<?0.01, adjusted odds ratio 1.049 (95 % CI 1.011–1.089, p?=?0.012). Vaginal resting pressure did not affect other delivery outcomes. Pelvic floor muscle strength and endurance similarly were not associated with any delivery outcomes.

Conclusions

While midpregnancy vaginal resting pressure is associated with prolonged second stage of labor, neither vaginal resting pressure nor pelvic floor muscle strength or endurance are associated with operative delivery or perineal tears. Strong pelvic floor muscles are not disadvantageous for vaginal delivery.  相似文献   
133.
134.
135.

Background

Posterior urethral valves (PUV) are a common cause of end-stage renal failure in childhood. Our aim was to describe a cohort of patients with PUV and to investigate the predictors of renal impairment.

Methods

We performed a retrospective chart review of children with PUV who were followed at King Abdulaziz University hospital between 2002 and 2011.

Results

The cohort comprised 68 boys. There was a significant difference in the duration of follow-up (p?=?0.024), nadir serum creatinine (p?<?0.001), and last known serum creatinine level (p?=?0.001) between the patients with and without renal impairment. The duration of follow-up appeared to be a significant predictor for serum creatinine doubling (p?=?0.003; odds ratio, 1.8). There was no difference in the age of presentation, age at the time of the study, and first or last serum creatinine between children who initially had vesicostomy and children who had ablation.

Conclusions

Ablation of PUV or vesicostomy did not influence kidney function in our study cohort. Children with a normal nadir serum creatinine who presented early had a better outcome.  相似文献   
136.
137.
Objectives. To assess the health related quality of life (HRQoL) and the change in the NYHA class after coronary artery bypass grafting (CABG) or percutaneous coronary intervention (PCI) in the management of stable coronary artery disease (CAD). The study was non-randomized. CABG group consisted of 240 patients and 229 patients were treated with PCI. HRQoL was measured prospectively by the 15D instrument. Results. Three-year survival was 95.0 and 95.6% (NS). The HRQoL improved statistically in both groups until 6 months after treatment but deteriorated towards the end of the follow-up of 36 months. Clinically evident improvement of the HRQoL and decrease of the NYHA class took place more frequently among CABG patients. Conclusions. Despite initially more serious preoperative state and more demanding procedure CABG patients achieve equal level of HRQoL when compared with PCI patients. CABG patients may also obtain better relief from symptoms in mid-term follow-up. HRQoL cannot be the only factor to determine outcome after invasive treatment of CAD but it has to be placed in the context of the overall situation.  相似文献   
138.
It is unclear whether symptoms of autism spectrum disorder (ASD) in young children in the population fit the three-factor structure of ASD as described in the DSM-IV, and cluster together in individual subjects. This study analysed questionnaire data on ASD symptoms filled in by mothers of 11,332 18-month-old children that was collected in the context of the Norwegian Mother and Child Cohort Study conducted by the Norwegian Institute of Public Health. Confirmatory Factor Analyses showed that the three-factor model had a significantly better fit then the two- and one-factor model of ASD symptoms. Latent class analysis revealed four homogeneous groups of children (classes) with different scores for Social Interaction and Communication at one hand and Stereotypies/Rigidity at the other hand.  相似文献   
139.
Mercury is a toxic metal shown to have harmful effects on human health. Several studies have reported high blood mercury concentrations as a risk factor for autism spectrum disorders (ASDs), while other studies have reported no such association. The goal of this study was to investigate the association between blood mercury concentrations in children and ASDs. Moreover, we investigated the role of seafood consumption in relation to blood mercury concentrations in Jamaican children. Based on data for 65 sex- and age-matched pairs (2?C8 years), we used a General Linear Model to test whether there is an association between blood mercury concentrations and ASDs. After controlling for the child??s frequency of seafood consumption, maternal age, and parental education, we did not find a significant difference (P = 0.61) between blood mercury concentrations and ASDs. However, in both cases and control groups, children who ate certain types of seafood (i.e., salt water fish, sardine, or mackerel fish) had significantly higher (all P < 0.05) geometric means blood mercury concentration which were about 3.5 times that of children living in the US or Canada. Our findings also indicate that Jamaican children with parents who both had education up to high school are at a higher risk of exposure to mercury compared to children with at least one parent who had education beyond high school. Based on our findings, we recommend additional education to Jamaican parents regarding potential hazards of elevated blood mercury concentrations, and its association with seafood consumption and type of seafood.  相似文献   
140.
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