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BACKGROUND CONTEXT: Retrolisthesis is relatively rare but when present has been associated with increased back pain and impaired back function. Neither the prevalence of this condition in individuals with lumbar disc herniations nor its possible relation to preoperative back pain and dysfunction has been well studied. PURPOSE: The purposes of this study were as follows: (1) to determine the prevalence of retrolisthesis (alone or in combination with other degenerative conditions) in individuals with confirmed L5-S1 disc herniation who later underwent lumbar discectomy; (2) to determine if there is any association between retrolisthesis and degenerative changes within the same vertebral motion segment; and (3) to determine the relation between retrolisthesis (alone or in combination with other degenerative conditions) and preoperative low back pain, physical function, and quality of life. STUDY DESIGN/SETTING: Cross-sectional study. PATIENT SAMPLE: A total of 125 individuals were identified for incorporation into this study. All patients had confirmed L5-S1 disc herniation on magnetic resonance imaging (MRI) and later underwent L5-S1 discectomy. All patients were enrolled in the Spine Patient Outcomes Research Trial (SPORT) study; data were obtained from the multi-institutional database comprised of SPORT patients from across the United States. OUTCOME MEASURES: Retrolisthesis, degenerative change on MRI, and Modic changes. METHODS: MRI scans of the lumbar spine were assessed at spinal level L5-S1 for all 125 patients. Retrolisthesis was defined as posterior subluxation of 8% or more. Disc degeneration was defined as any loss of disc signal on T2 imaging. Modic changes were graded 1 to 3 and collectively classified as vertebral endplate degenerative changes. The presence of facet arthropathy and ligamentum flavum hypertrophy was classified jointly as posterior degenerative changes. RESULTS: The overall incidence of retrolisthesis at L5-S1 in our study was 23.2%. Retrolisthesis combined with posterior degenerative changes, degenerative disc disease, or vertebral endplate changes had incidences of 4.8%, 16%, and 4.8% respectively. The prevalence of retrolisthesis did not vary by sex, age, race, smoking status, or education level when compared with individuals with normal sagittal alignment. However, individuals with retrolisthesis were more likely to be receiving workers' compensation than those without retrolisthesis. Increased age was found to be associated with individuals having vertebral endplate degenerative changes (both alone and in conjunction with retrolisthesis) and degenerative disc disease. Individuals who had retrolisthesis with concomitant vertebral endplate degenerative changes were more often smokers and had no insurance. The presence of retrolisthesis was not associated with an increased incidence of having degenerative disc disease, posterior degenerative changes, or vertebral endplate changes. No statistical significance was found between the presence of retrolisthesis on the degree of patient preoperative low back pain and physical function. Patients with degenerative disc disease were found to have increased leg pain compared with those patients without degenerative disc changes. CONCLUSIONS: We found no significant relationship between retrolisthesis in patients with L5-S1 disc herniation and worse baseline pain or function. It is possible that the contribution of pain or dysfunction related to retrolisthesis was far overshadowed by the presence of symptoms caused by the concomitant disc herniation. It remains to be seen whether retrolisthesis will affect outcome after discectomy in these patients.  相似文献   
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Studies have shown a high correlation between measurements of bone mineral density (BMD) obtained on differentdual-energy X-ray absorptiometry machines. Challenger osteodensitometers (Diagnostic Medical System [DMS],Montpellier, France) are becoming widely used but little is known about their clinical performance. The aim of this study was to compare BMD measurements and the resulting patient classification based on T-scores obtained on a DMS Challenger device to those obtained on Hologic 4500A (Bedford, MA) device. Fifty-three volunteers were studied.The BMD of the spine and of the hip were simultaneously measured on both densitometers. BMD values obtained on the Challenger were significantly higher than those obtained with the Hologic QDR4500 (p<0.001). The correlations coefficients between the Hologic QDR4500 and the DMS Challenger measured BMDs were r=0.70 at the femoral neck, r=0.70 at the trochanter, and r=0.83 at the spine (p<0.001). Among the 35 postmenopausal women, there was discordance in the WHO T-score-based classification in 28 subjects (80%) at the spine, 18 subjects (52%) at the femoral neck, and 14 subjects (42%) at the trochanter. The intermachine agreement was low: The kappa score was -0.10 at the spine, 0.2 at the femoral neck, and 0.3 at the trochanter. In conclusion, this study cautions against the use of non established densitometers that leads to underdiagnosis of patients and, subsequently, to inappropriate treatment strategies.  相似文献   
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Journal of Prevention - Excessive smartphone use leads to several physical and psychological disorders, particularly among young adults. This study aimed to investigate the prevalence and the...  相似文献   
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ObjectivesTo examine how postoperative pain control after robotic thoracoscopic surgery varies with liposomal bupivacaine (LipoB) versus 0.5% bupivacaine/1:200,000 epinephrine (Bupi/Epi) intercostal nerve blocks within the context of an enhanced recovery after thoracic surgery (ERATS) protocol.DesignA retrospective analysis of a prospectively maintained database of patients undergoing robotic thoracoscopic procedures between September 1, 2018 and October 31, 2019 was conducted.SettingUniversity of Miami, single-institutional.ParticipantsPatients.InterventionsTwo hundred fifty-two patients had either LipoB intercostal nerve blocks (n = 129) or Bupi/Epi intercostal nerve blocks (n = 123) when undergoing robotic thoracic surgery.Measurements and Main ResultsComparative analysis of patient-reported pain levels, in-hospital and post-discharge opioid requirements, 90-day operative complications, length of hospital stay, and hospital costs was performed. Data were stratified to either anatomic lung resection or pulmonary wedge resection/mediastinal-pleural procedures. Bupi/Epi patients reported significantly more acute postoperative pain than LipoB patients, which correlated with higher in-hospital and post-discharge opioid requirements. There were no differences in postoperative complications, length of hospital stay, or hospital costs between the two groups.ConclusionsAs part of an ERATS protocol, infiltration of intercostal spaces and surgical wounds with LipoB for robotic thoracoscopic procedures afforded better postoperative subjective pain control and decreased opioid requirements without an increase in hospital costs as compared with use of Bupi/Epi.  相似文献   
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For choosing an anaesthetic agent for a particular purpose, the different properties has been notified such as the convenience for use, safety for the fish, humans and the environment, effectiveness, physiological disturbances and its cost. Invariably, in any study with clove oil, it has been regarded as an effective and acceptable alternative to other anaesthetics. The aim of the present study was to investigate effects of two anaesthetic regimes, MS-222 and eugenol, on plasma biochemical parameters in Barbus sharpeyi. B. sharpeyi fingerlings (mean weight, 5?g?±?1; mean length, 6?cm?±?1) were exposed to MS-222 (100?ppm) and eugenol (40?ppm) for induction of anaesthesia. Blood samples were taken to verify the effects of these anaesthetics on plasma biochemical parameters may use as an indicator of stress at time 0 (designated for each tank at the time of exposure to anaesthetic agent), 0.5, 1, 2 and 24?h after exposure by caudal severance. Plasma biochemical parameters concentrations were not significantly affected in B. sharpeyi (p?<?0.05). These results were expected because the trials were conducted in short-term exposures. Ion balance appears to be altered only in long-term stressing condition. Based on the results of this study, eugenol appears to be a safe anesthetic for use in B. sharpeyi.  相似文献   
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Patients with asthma develop pulmonary hypertension due to recurrent hypoxia and chronic inflammation, leading to right heart enlargement with ventricular hypertrophy. Patients with severe asthma can experience cor pulmonale later in life, but little is known about ventricular function during the early stages of the disease. This study aimed to investigate ventricular functions in asymptomatic children with asthma as detected by conventional echocardiography and tissue Doppler echocardiography (TDE). Fifty-one pediatric patients (mean age 10.4 ± 2.2 years) with asthma and 46 age- and sex-matched healthy children (mean age 10.9 ± 2.4 years) were studied. All subjects were examined by conventional echocardiography and TDE, and they had pulmonary function tests on spirometry. The right-ventricular (RV) wall was statistically (p = 0.01) thicker among asthmatic patients (4.7 ± 1.5 mm) compared with healthy children (3.6 ± 0.4 mm). However, conventional pulsed-Doppler indices of both ventricles did not differ significantly between asthmatic patients and healthy children (p > 0.05). The results of TDE examining RV diastolic function showed that annular peak velocity during early diastole (E′), annular peak velocity during late diastole (A′) (16.4 ± 1.8 and 5.1 ± 1.4 cm/s, respectively), E′/A′ ratio (3.2 ± 0.7), isovolumetric relaxation time (67.7 ± 10.2 ms) and myocardial performance index (48.1 % ± 7.0 %) of the lateral tricuspid annulus among asthmatic patients differed significantly (p = 0.01) from those of healthy children (13.2 ± 2.3, 8.2 ± 2.0 cm/s, 1.6 ± 0.5, 46.2 ± 8.7 ms, and 42.0 % ± 5.7 %, respectively). Only peak expiratory flow (PEF) rate from the pulmonary function tests was negatively correlated with the E′/A′ ratio of the tricuspid annulus (r = ?0.38, p = 0.01). This study showed that although the findings of clinical and conventional echocardiography were apparently normal in children with asthma, TDE showed subclinical dysfunction of the right ventricle, which is negatively correlated with PEF. These findings signify the diagnostic value of TDE in the early detection and monitoring of such deleterious effects among asthmatic patients.  相似文献   
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