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91.

Background

The critical shoulder angle (CSA) has been reported to be associated with rotator cuff disease and has been suggested as an etiology for cuff tears. However, it is unclear whether acromial morphologic characteristics such as CSA are a cause or effect because all studies to date have been retrospective.

Questions/purposes

(1) How often can the CSA be reliably measured? (2) Is the CSA associated with rotator cuff disease? (3) Is the CSA correlated with baseline tear size or tear enlargement? (4) Does the CSA change with time?

Methods

In this retrospective comparison of longitudinally collected data, patients with asymptomatic rotator cuff tears underwent ultrasonography and standardized AP radiographs at enrollment and yearly thereafter during a median of 4 years. Three hundred ninety-five patients were included, of whom 14 were excluded as they were not yet eligible for 2-year followup and 68 (18%) were lost to followup, leaving 313 study patients who were evaluated with 1433 radiographs. Patients with adhesive capsulitis with normal rotator cuffs and radiographically normal scapulae were included as control subjects (119 subjects). Two observers (PNC, DS) measured the CSA in a blinded fashion. Radiographs that met Suter-Henninger criteria for CSA measurement reliability were included. For the study group, 179 of the 313 (57%) patients with radiographs that met Suter-Henninger criteria were further analyzed; the remainder were excluded from this study. For the control group, 50 of 119 (42%) subjects met criteria and were further analyzed. Tear enlargement was found in 94 patients, and the CSA was compared in patients with tears and control subjects, and in tears with or without enlargement, and was correlated with tear size. In a subgroup of the study group in which 59 of 179 patients had a minimum of 3 years between initial and followup radiographs, two CSA measurements were performed to measure change.

Results

In total, of the 1552 radiographs evaluated, only 326 (21%) were of sufficient quality to measure the CSA. The CSA was higher among patients with cuff tears than control subjects (34° ± 4° versus 32° ± 4°; mean difference, 2.0°; 95% CI, 0.7°–3.2°; p = 0.003). The CSA did not correlate with baseline tear length (ρ = 0.22, p = 0.090) or width (ρ = 0.16, p = 0.229). The CSA was not different between tears that enlarged and those that were stable (34° ± 3° versus 34° ± 4°; mean difference, 0.2°; 95% CI, ?0.9° to ?1.4°; p = 0.683). The CSA did not change over time (CSA Time 1: mean 33° ± 4° SD; CSA Time 2: mean 33° ± 4° SD; mean difference, ?0.2°; 95% CI, ?0.6° to 0.1°; p = 0.253).

Conclusions

Even with a longitudinal protocol, most radiographs are of insufficient quality for CSA measurement. Although patients with a history of degenerative cuff disease have higher CSA values than control subjects, the difference is small enough that it could be influenced by measurement error in practice; in any case, a difference of the magnitude we observed is likely to be clinically unimportant. The CSA is not correlated with tear size or tear progression, and does not seem to change with time. These results suggest that the CSA is unlikely to be related to rotator cuff disease.

Level of Evidence

Level II, prognostic study.
  相似文献   
92.
Major depressive disorder is prevalent worldwide, and only about half of those affected will experience no further episodes or symptoms. Additionally, depressive symptoms can be challenging to identify, with many patients going undiagnosed despite a wide variety of available treatment options. Antidepressants are the cornerstone of depression treatment; however, a large number of factors must be considered in selecting the treatment best suited to the individual. To help support physicians in this process, international and national treatment guidelines have been developed. This review evaluates the current use of antidepressant treatment for major depressive disorder in six Asian countries (China, Korea, Malaysia, Philippines, Taiwan, and Thailand). No remarkable differences were noted between Asian and international treatment guidelines or among those from within Asia as these are adapted from western guidelines, although there were some local variations. Importantly, a shortage of evidence‐based information at a country level is the primary problem in developing guidelines appropriate for Asia, so most of the guidelines are consensus opinions derived from western research data utilized in western guidelines. Treatment guidelines need to evolve from being consensus based to evidence based when evidence is available, taking into consideration cost/effectiveness or cost/benefit with an evidence‐based approach that more accurately reflects clinical experience as well as the attributes of each antidepressant. In everyday practice, physicians must tailor their treatment to the patient's clinical needs while considering associated external factors; better tools are needed to help them reach the best possible prescribing decisions which are of maximum benefit to patients.  相似文献   
93.
Management of an indeterminate pulmonary nodule is a diagnostic challenge that commonly confronts primary care physicians and specialists. Patients often present with this radiographic finding in the course of an unrelated medical evaluation. We examined our institution's experience with percutaneous biopsy of lung nodules to determine the impact of this procedure on overall patient care. Although significant complications are uncommon, the expedience of percutaneous lung biopsy often supplants a surgical opinion prior to initiation of therapy without added diagnostic benefit or cost-savings. Hence, we caution practitioners to use this technique as an adjunct to diagnosis and not a substitute for multidisciplinary care.  相似文献   
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IntroductionSimultaneous gastrostomy tube (GT) and tracheostomy placement in young children offers potential benefit in limiting anesthetic exposure, but it is unknown whether combining these procedures introduces additional morbidity. This study compared outcomes after combined GT and tracheostomy placement versus GT placement alone among similar ventilator-dependent patients.MethodsVentilator-dependent children <2-years-old who underwent GT placement alone (MV-GT), simultaneous GT and tracheostomy placement (GT+T), and GT placement alone with a pre-existing tracheostomy (T-GT) were identified using 2012–2018 NSQIP-Pediatric Participant User Files. Multiple logistic regression models were used to compare outcomes while adjusting for other group differences.ResultsAmong 1100 children, 351 underwent MV-GT, 494 GT+T, and 255 T-GT. Major complications occurred in 23.6%, 17.0%, and 14.5% of the respective groups (p = 0.01). Major complications with GT+T were similar to T-GT (adjusted odds ratio [aOR]=1.19, 95%CI:0.78–1.83, p = 0.4) and lower than MV-GT (aOR=0.67, 95%CI:0.47–0.95, p = 0.02). Severe complications including mortality, cardiac arrest, and stroke were similar between the three groups (p = 0.8).ConclusionsChildren <2-years-old undergoing GT+T did not experience higher post-operative complications compared to children undergoing T-GT or MV-GT. Utilizing GT+T to limit anesthetic exposure may be reasonable within this high-risk population.Type of StudyTreatment StudyLevel of EvidenceLevel III  相似文献   
96.
The aetiology of idiopathic Parkinson's disease (PD) is poorly defined but environmental aggression may be relevant. Here, we report a new model of PD in mice, based on chronic inoculation with neurotoxins in the nasal cavity, which is a natural route of contact with the environment. C57BL/6 mice, submitted to daily intranasal inoculation with MPTP for 30 days, developed motor deficits that correlated with a progressive and severe depletion of striatal dopamine levels, and loss of tyrosine hydroxylase and dopamine transporter staining in substantia nigra and striatum. Moreover, mice intranasally inoculated with MPTP developed strong astrogliosis and microgliosis in substantia nigra and striatum. Consistent with these observations, a role for oxidant aggression was demonstrated by increased levels of Mn-superoxide dismutase. However, alpha-synuclein aggregation was not observed. This new animal model provides a new tool for studying PD symptoms that develop slowly over time, and it may be used to asses risk from environmental neurotoxins.  相似文献   
97.
Chronic lung allograft dysfunction (CLAD) is a major cause of mortality in lung transplant recipients. CLAD can be sub‐divided into at least 2 subtypes with distinct mortality risk characteristics: restrictive allograft syndrome (RAS), which demonstrates increased overall computed tomography (CT) lung density in contrast with bronchiolitis obliterans syndrome (BOS), which demonstrates reduced overall CT lung density. This study aimed to evaluate a reader‐independent quantitative density metric (QDM) derived from CT histograms to associate with CLAD survival. A retrospective study evaluated CT scans corresponding to CLAD onset using pulmonary function tests in 74 patients (23 RAS, 51 BOS). Two different QDM values (QDM1 and QDM2) were calculated using CT lung density histograms. Calculation of QDM1 includes the extreme edges of the histogram. Calculation of QDM2 includes the central region of the histogram. Kaplan‐Meier analysis and Cox regression analysis were used for CLAD prognosis. Higher QDM values were significantly associated with decreased survival. The hazard ratio for death was 3.2 times higher at the 75th percentile compared to the 25th percentile using QDM1 in a univariate model. QDM may associate with CLAD patient prognosis.  相似文献   
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The traditional cytotoxic agents are of limited efficacy in the treatment of neuroendocrine tumors of the gastrointestinal tract (NETs). Recent investigations have brought up a number of biological features in this family of neoplasms that could represent targets for anticancer treatment. NETs seem to have an extraordinary tumor vascularization with high expression of proangiogenic molecules such as the vascular endothelial growth factor along with overexpression of certain tyrosine kinase receptors such as the epidermal growth factor receptor (EGFR), the insulin growth factor receptor (IGFR) and their downstream signaling pathway components (PI3K-AKT-mTOR). The rationale of an antiangiogenic approach in the treatment of NETs and the use of other pharmacological strategies such as EGFR, IGFR and mammalian target of rapamycin inhibitors are discussed. Additionally, the emerging results of recent clinical trials with these targeted drugs are presented.  相似文献   
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