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1.

Background

Obesity is a risk factor for acetabular component malposition when total hip arthroplasty is performed with manual techniques. The utility of imageless navigation in obese patients remains unknown. This study compared the accuracy and precision of imageless navigation for component orientation between obese and nonobese patients.

Methods

A total of 459 total hip arthroplasties performed for osteoarthritis using imageless navigation were reviewed from a single surgeon’s institutional review board–approved database. Einzel-Bild-Roentgen Analyse determined component orientation on 6-week postoperative anteroposterior radiographs. Mean orientation error (accuracy) and precision were compared between obese (body mass index ≥ 30 kg/m2) and nonobese patients. Regression analysis evaluated the influence of obesity on component position.

Results

The difference in mean inclination and anteversion between obese and nonobese groups was 1.1° (43.0° ± 3.5°; range, 35.8°-57.8° vs 41.9° ± 4.4°; range, 33.0°-57.1° and 24.9° ± 6.3°; range, 14.2°-44.3° vs 23.8° ± 6.6°; range, 7.0°-38.6°, respectively). Inclination precision was better for nonobese patients. No difference in inclination accuracy or anteversion accuracy or precision was detected between groups. And 83% of components were placed within the target range. There was no relationship between obesity (dichotomized) and component placement outside the target ranges for inclination, anteversion, or both. As a continuous variable, increased body mass index correlated with higher odds of inclination outside the target zone (odds ratio, 1.06; P = .001).

Conclusion

Using imageless navigation, inclination orientation was less precise for obese patients, but the observed difference is likely not clinically relevant. Accurate superficial registration of landmarks in obese patients is achievable, and the use of imageless navigation similarly improves acetabular component positioning in obese and nonobese patients.

Level of Evidence

Therapeutic Level IV.  相似文献   
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Background. Medication adherence impacts healthcare utilization. Pharmacy records are useful to establish fill patterns. Objective. Use pharmacy records to establish medication patterns fill patterns for comparison to healthcare utilization. Methods. Pharmacy records of 175 children with persistent asthma were collected and compared to healthcare utilization. Results. Majority of subjects had significant healthcare utilization, low numbers of rescue medications, and poor controller medication fill rates. Those with more rescue medications had more healthcare utilization and more controller medications. Conclusions. Pharmacy fill patterns demonstrate few rescue and/or controller medication fills. Those with more rescue medications reported increased healthcare utilization despite controller medications.  相似文献   
4.
The mortality profile of female nurses and teachers in British Columbia (BC) was examined using age-standardized proportional mortality ratios (PMRs) calculated for the period 1950–1984. Lowered overall mortality among nurses was seen for degenerative heart disease and for cerebrovascular accidents. Significantly elevated PMR values were observed for cancer of the breast and ovary in nurses of age 20–65 years. PMRs were significantly elevated for cancer of the pancreas and leukemia among those age 20 years and older. Elevated values were also observed for motor vehicle accidents and suicide among nurses in both age groups. Lower than expected mortality from degenerative heart disease and cerebrovascular accidents was seen in working age teachers (age 20–65 years). However, elevated PMRs were detected for carcinoma of the colon, breast, endometrium, brain, and melanoma. Among those 20 years and over, significantly elevated PMRs were also observed for cancers of the ovary and other digestive organs. Elevated PMRs were found for motor vehicle and aircraft accidents. Mortality from cirrhosis of the liver was lower than anticipated in both teachers and nurses. A number of significant PMRs declined when deaths of “homemakers” were withdrawn from the comparison group used to generate PMR values, suggesting that risk of death from various causes among women working outside the home differ from those seen in women who are predominantly in the home.  相似文献   
5.
Paraneoplastic hypercalcemia associated with adenosquamous carcinoma of the endometrium is described. This is the first reported case of a gynecologic cancer in which the paraneoplastic syndrome has been conclusively shown by immunohistochemical analysis to be due to ectopic parathormone.  相似文献   
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The chick embryo chorioallantoic membrane was used to study the acute inflammatory response in the absence of contributions from the immune system. In preliminary experiments, lesions of wild-type cowpox virus strain Brighton (CPV-BR) and a 38K gene deletion mutant of CPV-BR (CPV-BR.D1) were compared with vaccinia virus (strains WR and Copenhagen), fowlpox virus, laryngotracheitis virus, and infectious tenosynovitis virus, and were ranked for degree of induced inflammation. The maximal and minimal inflammatory responses were observed with CPV-BR.D1 and CPV-BR viruses, respectively. CPV-BR.D1 lacks a 38K gene which encodes an anti-inflammatory 38-kDa protein that has homology to SERPINs. The kinetics and character of the inflammatory response were examined further in the wild-type CPV-BR and mutant CPV-BR.D1 infections using cell counts, electron microscopy, and assays for inflammatory cell activation. CPV-BR virus infection rapidly spread through the ectoderm, uniformly infecting all cells with the production of large amounts of virions and viral-induced cytopathic effect, but evoking little or no inflammatory response until 144 hr p.i. The CPV-BR.D1 infection, on the other hand, was rapidly contained by a dexamethasone-sensitive inflammatory response mainly of activated heterophils which was advanced by 36 hr p.i. Both infections resulted in disseminated disease with similar numbers of liver lesions and only a slight difference in the LD50, with the CPV-BR.D1 values being higher than that for CPV-BR virus. In this model, the acute inflammatory response alone is unable to prevent disseminated disease and associated mortality.  相似文献   
8.

Previous studies have shown that engagement strategies can help increase enrollment and initiation of families in evidence-based preventive programs under natural service delivery settings. However, little is known about factors that predict completion of these engagement strategies. This study aimed to examine predictors (i.e., perceived need, perceived barriers, and sociocultural context) of caregiver participation in an evidence-based engagement call strategy. This call was expected to increase initiation into a school-based, family-focused prevention program. In addition, this study examined engagement call completion as a predictor of program initiation among already enrolled families. Participants included ethnically diverse families recruited from three Title I schools (n = 413) who were randomized to receive the prevention program. Results showed that interparental conflict—an indicator of perceived need—was associated with an increased likelihood of completing the engagement call. Furthermore, caregivers from low-socioeconomic status (SES), foreign-born, Spanish-speaking, Hispanic families were more likely to complete the call relative to those from low- and mid-SES, US born, English-speaking, ethnically diverse families. Importantly, engagement call completion was associated with an increased likelihood of program initiation. These findings provide limited support that families with higher perceived needs are more likely to participate in an evidence-based engagement call strategy. Results suggested that the call strategy provides a promising way to reduce attrition from family prevention programs, which is commonly observed between enrollment and initiation. Project Number: R01 DA035855; Date of Registration: 06/15/2014.

  相似文献   
9.
Buller KM  Smith DW  Day TA 《Neuroreport》1999,10(18):3853-3856
Immunolabelling for Fos and tyrosine hydroxylase was used to determine the patterns of activation of nucleus tractus solitarius catecholamine cells in response to graded levels of hemorrhage (0, 4, 8, 12 and 16 ml/kg) and systemic hypoxia (21, 14, 12, 10 and 8% O2) in conscious rats. Both stimuli elicited graded catecholamine cell recruitment with thresholds of 8 ml/kg and 12% O2. The majority of responsive neurons were A2 noradrenergic rather than C2 adrenergic cells. After hemorrhage most Fos-positive catecholamine cells were found below obex whereas most hypoxia-responsive cells were rostral to obex. These distinctive patterns of catecholamine cell recruitment may explain the differences in neuroendocrine responses to these stimuli.  相似文献   
10.
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