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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   
2.
The authors present a case of rickets in an adolescent girl who presented to the emergency department with bone pain. Emergency department staff should be aware that rickets is not just a disease of early childhood.  相似文献   
3.
PURPOSE: Despite general worldwide acceptance of the concept of neurological determination of death (NDD), inconsistencies in clinical criteria and ancillary testing requirements remain. Numerous guidelines for NDD may be applied in clinical practice by a variety of medical practitioners, but the scientific rationale for specific guideline recommendations often remains unclear. This review examines the evolution of NDD, and seeks to provide scientific validation for existing NDD criteria. SOURCE: English language peer-reviewed medical journals and established contemporary medical texts. PRINCIPAL FINDINGS: Currently published guidelines appear to have evolved from the work of the ad hoc Committee of the Harvard Medical School to Examine the Definition of Brain Death. The Conference of the Royal Colleges and Faculties of the United Kingdom refined the criteria and subsequently adopted the principal of brainstem death. While the fundamentals of NDD guidelines are remarkably consistent worldwide, specific criteria and requirements are often inconsistent. CONCLUSION: Numerous controversies regarding NDD continue to exist, necessitating further scientific clarification of these issues. More recently published guidelines representing the collective opinion of world experts in NDD based upon best current scientific evidence are available in current medical journals.  相似文献   
4.
Inborn errors of the urea cycle are an important cause of hyperammonaemia throughout childhood, and are associated with high morbidity and mortality rates. If they are diagnosed early and treated appropriately, the outcome for affected children is significantly improved.  相似文献   
5.
6.
Caffeine is the most widely consumed drug in Western society. The intake of caffeine-containing beverages in many adults and children often reaches levels that can induce pharmacological effects. Ninety-nine percent of ingested caffeine is absorbed and distributed to all tissues and organs. The effects of caffeine intake differ greatly according to acute or chronic intake, level of intake, and the development of tolerance. Caffeine administered acutely to non-users or recent abstainers can induce hypertension, arrhythmias, altered myocardial function, increased plasma catecholamine levels, plasma renin activity, serum cholesterol levels, increased production of urine, gastric acid secretion, and alterations in mood and sleep patterns. Tolerance to chronic caffeine intake develops in most individuals, with the cessation of its effects on the renal system, the cardiovascular system, the gastrointestinal system and, to some extent, the central nervous system. Moderate caffeine consumers probably need to have little concern for the effect of caffeine intake on their health if their other life-style habits are also moderate.  相似文献   
7.
8.
This study evaluated the effects of tobacco Purchase, Use and Possession (PUP) laws on student perceptions of adolescent tobacco use within towns and schools. Twenty‐four towns were randomly assigned into two conditions, the experimental condition (E PUP) involved efforts to increase both PUP law enforcement and reduce minors' access to commercial sources of tobacco, whereas the control condition (C) focused only on efforts to reduce minors' access to commercial sources of tobacco. A hierarchical linear modeling analytical approach was selected due to the multilevel data and nested design. The present study found that over time, youth in the experimental PUP condition observed less youth tobacco usage at school and in their town, and perceived lower rates of tobacco among their peers at school and among friends than youth in the control condition. The findings suggest that PUP law enforcement might be used to strengthen community norms against youth tobacco use.  相似文献   
9.
Rift Valley fever (RVF) virus infection, dissemination, and transmission rates were determined for Aedes fowleri, Aedes mcintoshi and Culex pipiens 7 or 10 days after sequentially feeding to repletion on RVF virus immune hamsters and RVF viremic hamsters, or after feeding on a mixture of RVF virus immune sheep serum and RVF viremic hamster blood through a pledget. No significant differences in infection or dissemination rates were detected among Ae. fowleri and Cx. pipiens feeding to repletion on immune hamsters before or after feeding to repletion on a viremic hamster. Similarly, no significant differences in infection, dissemination, or transmission rates were observed among Ae. fowleri and Cx. pipiens feeding to repletion on immune hamsters or nonimmune (control) hamsters 0 or 24 hr after inoculation with RVF virus. Infection rates were significantly higher for Ae. fowleri (56/66, 85%) and Cx. pipiens (123/148, 83%) fed only on viremic hamsters than for those interrupted to complete feeding on an immune hamster (Ae. fowleri [24/49, 59%], Cx. pipiens [66/131, 50%]) or a nonimmune hamster (Ae. fowleri [32/51, 63%], Cx. pipiens [69/127, 54%]). However, no significant differences were detected in infection, dissemination, or transmission rates among Ae. fowleri, Ae. mcintoshi or Cx. pipiens fed on a viremic hamster and interrupted to complete feeding on an immune vs. a nonimmune hamster. Results from interrupted feeding experiments were significantly different from pledget feeding experiments.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
10.
Abstract We report a case of SMV injury in a critically ill patient. The patient was a 19-year-old woman involved in a motor vehicle collision. Her injuries included grade II splenic and renal lacerations, devascularized and lacerated right and transverse colon, a transected transverse mesocolon, a massive shear injury of her abdominal wall, and two partial SMV transections. At initial damage control laparotomy, the SMV was ligated, the devascularized bowel resected and a temporary abdominal closure applied. At re-operation, a mesocaval shunt using saphenous vein was employed. The shunt failed and the patient required a saphenous vein jump graft. Although visceral vascular injuries are rare, ligation of the SMV in a damage control situation is acceptable. This case study is the first to discuss appropriate treatment when interruption to a patient's collateral visceral venous drainage limits the surgeon’s ability to ligate. In these situations, bypass shunts may be successful.  相似文献   
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