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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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We have identified the A3243G heteroplasmic point mutation in mitochondrial DNA from a female patient with headache as the main clinical feature. The mitochondrial origin of her disease was only suspected because of her brother with MELAS syndrome. Morphological and biochemical studies failed to reveal mitochondrial respiratory chain dysfunction in her muscle which contained 65% of mutated mitochondrial DNA molecules. Molecular studies performed among four generations (in the blood of seven subjects) showed the variable transmission of mutated molecules and pointed out the difficulty in giving genetic counsel.  相似文献   
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Computed tomography angiogram of the head and neck has lately become a pivotal imaging modality in the patient with acute stroke symptoms due to its high resolution, accuracy, speed, and sensitivity in the assessment of brain parenchyma and vascular patency.  相似文献   
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AIMS: To show that a thrice daily meal-time biphasic insulin aspart (BIAsp) treatment regimen is as efficacious as a 4 times daily basal-bolus regimen with human isophane insulin (NPH) and insulin aspart (IAsp). METHODS: A multinational, randomised, open-label parallel-group trial in 394 patients with type 2 diabetes on a once or twice daily insulin regimen. Patients were randomised 1:1 to BIAsp or IAsp+NPH for 16 weeks. The BIAsp group was treated according to individual needs using BMI as a surrogate index of insulin resistance. Subjects administered BIAsp 70 (BMI< or =30 kg/m (2)) or BIAsp 50 (BMI>30 kg/m (2)) with breakfast and lunch and BIAsp 30 with dinner. The IAsp+NPH group injected IAsp at meals and NPH at bedtime as basal insulin. HbAlc levels after 16 weeks were compared between treatments using a predefined non-inferiority criterion of 0.4%. The incidence of hypoglycaemic episodes and adverse events was evaluated. RESULTS: Mean HbAlc (+/-SD) decreased from 9.1+/-0.7% to 7.8+/-1.0% with both treatments. Glycaemic control provided by BIAsp was non-inferior to that obtained by the IAsp+NPH (intention to treat ITT) population: diff, HbAlc -0.05%; 95% CI (-0.24; 0.14); per protocol (PP) population: diff, HbAlc -0.03%; 95% CI (-0.23; 0.16). Similar improvements in glycaemic control in both groups were confirmed by self-measured 8-point plasma glucose (PG) profiles, average and fasting PG concentrations, and average prandial PG increments. The incidence of adverse events and hypoglycaemic episodes was similar in the two treatment groups. CONCLUSIONS: A thrice daily meal-time BIAsp regimen is a suitable alternative to an intensified insulin regimen in people with inadequately controlled type 2 diabetes mellitus, and requires fewer daily injections than a basal-bolus therapy without compromising efficacy and safety.  相似文献   
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The present work tries to establish the antioxidant capacity of the peripheral nervous tissue of the rat, in terms of the enzymatic activities present in this tissue that either prevent the formation of activated species as the semiquinone radical (DT-diaphorase), protect against activated oxygen species (superoxide dismutase, glutathione peroxidase), conjugate natural toxic products or xenobiotics (glutathione S-transferases, especially the activity conjugating 4-hydroxy-nonenal), or complete the glutathione system metabolism (glutathione disulfide reductase, γ-glutamyl transpeptidase). All the activities studied are lower in this tissue than they are in liver, except for γ-glutamyl transpeptidase. The relevance of the results obtained and its possible relationship with different neuropathies is discussed. It is concluded that the peripheral nervous tissue is by far less protected than the liver against oxidative damage.  相似文献   
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The authors present a patient with a complex vascular malformation composed of bilateral spontaneous carotid-cavernous fistulas (CCF's). The abnormality was supplied on the right side by the right external carotid artery (ECA) and the right internal carotid artery (ICA), and on the left side only by the left ICA. There was also an arteriovenous communication between the right ECA and the lateral sinus. Surgical embolization of both cavernous sinuses with oxidized cellulose was achieved on one side by direct puncture and on the other through one of its venous affluents, successfully occluding both CCF's and preserving the patency of both ICA's without any neurological deficit. The arteriovenous communication between the right ECA and the lateral sinus was occluded by embolization of the occipital artery and ligation of the right ECA.  相似文献   
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Chondroblastoma, a rare bone tumor usually found in the epiphyseal region of long bones, appeared in the rib of a 49-year-old man. Review of the literature reveals that the most common locations for this tumor are the knee and proximal humerus. The most common age group is the second decade. Eighteen cases of chondroblastoma of the rib have been reported in the literature; the patients were older than typical patients with epiphyseal chondroblastoma and had an excellent prognosis after resection of the tumor.  相似文献   
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