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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

Treatment of advanced anal squamous cell cancer (SCC) is usually with the combination of cisplatin and 5-fluorouracil, which is associated with heterogeneous responses across patients and significant toxicity. We examined the safety and efficacy of a modified schedule, FOLFCIS (leucovorin, fluorouracil, and cisplatin), and performed an integrated clinical and genomic analysis of anal SCC.

Patients and Methods

We reviewed all patients with advanced anal SCC receiving first-line FOLFCIS chemotherapy – essentially a FOLFOX (leucovorin, fluorouracil, and oxaliplatin) schedule with cisplatin substituted for oxaliplatin – in our institution between 2007 and 2017, and performed deep sequencing to identify genomic markers of response and key genomic drivers.

Results

Fifty-three patients with advanced anal SCC (48 metastatic; 5 unresectable, locally advanced) received first-line FOLFCIS during this period; all were platinum-naive. The response rate was 48% (95% confidence interval [CI], 32.6%-63%). With a median follow-up of 41.6 months, progression-free survival and overall survival were 7.1 months (95% CI, 4.4-8.6 months) and 22.1 months (95% CI, 16.9-28.1 months), respectively. Among all patients with advanced anal SCC that underwent sequencing during the study period, the most frequent genomic alterations consisted of chromosome 3q amplification (51%) and mutations in PIK3CA (29%) and KMT2D (22%). No genomic alteration correlated with response to platinum-containing treatment. Although there were few cases, patients with human papillomavirus-negative anal SCC did not appear to benefit from FOLFCIS, and all harbored distinct genomic profiles with TP53, TERT promoter, and CDKN2A mutations.

Conclusions

FOLFCIS appears effective and safe as first-line chemotherapy in patients with advanced anal SCC and represents an alternative treatment option for these patients.  相似文献   
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PURPOSE: To identify clinical prognostic factors in children with stage I, favorable histology (FH) Wilms' tumor treated with vincristine monochemotherapy after immediate nephrectomy to define subgroups for consideration of further reduction in treatment intensity. PATIENTS AND METHODS: During two consecutive trials of the United Kingdom Children's Cancer Study Group (UKW2 and UKW3, 1986 to 2001), 242 children with stage I FH Wilms' tumor were treated with immediate nephrectomy followed by 10 weekly injections of vincristine 1.5 mg/m2. Event-free survival (EFS) and overall survival (OS) were compared by age group. RESULTS: The 4-year EFS rate was 93.2%, 87.2%, and 71.3% for children less than 2 years old, 2 to 4 years old, and 4 years old or older at diagnosis, respectively (log-rank, P =.001); the corresponding 4-year OS rate was 98.1%, 95.0%, and 87.2% (log-rank, P =.01). There were no toxicity- or procedure-related deaths. In multivariate analysis, specimen weight was not of independent prognostic value (P =.66). Among the 186 children younger than 4 years at diagnosis, there were 17 relapses and five deaths, compared with 16 relapses and eight deaths among the 56 children at least 4 years old at diagnosis. OS after relapse was surprisingly poor (61.6% at 4 years). CONCLUSION: Treatment for stage I FH Wilms' tumor is generally successful using vincristine monotherapy after immediate nephrectomy, and therefore, the risks of dactinomycin hepatopathy can be avoided. However, age at least 4 years is a significant adverse prognostic factor. This treatment schedule should be considered in any trial of treatment reduction in very young children with stage I FH Wilms' tumor, regardless of tumor size, and we suggest that the upper age limit for the reduced therapy be set at 4 years.  相似文献   
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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   
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