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61.
BackgroundOxidized zirconium (OxZi) is a relatively new type of material that combines the strength of a metal with the surface/wears properties of a ceramic. Our aim was to investigate whether OxZi femoral heads lead to lower polyethylene wear, higher survival rate, and better clinical outcomes than the other bearing types in patients treated with total hip arthroplasty (THA).MethodsTwo reviewers independently conducted a systematic search according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses using the MEDLINE/PubMed database and the Cochrane Database of Systematic Reviews. These databases were queried with the terms: a. “oxidized” AND “zirconium” AND “total” AND “hip” AND “arthroplasty”; b. “oxinium” AND “total” AND “hip” AND “arthroplasty”. The primary outcome measures were the survival rate of the bearing surfaces as well as the polyethylene wear.ResultsThe vast majority (85.7%) of the studies, which reported the mean polyethylene wear rate, showed that there was not any significant difference between OxZi and cobalt-chrome (CoCr) femoral heads (rate ratio: 0.836; 95% confidence interval: 0.362-1.928; P = .674). All studies comparing the survival rate of OxZi and CoCr femoral heads illustrated almost excellent survivorship with both implants.ConclusionOxZi femoral heads did not lead to lower polyethylene wear rate or higher survival rate, when compared with CoCr femoral heads in patients treated with THA. On the basis of these results and taking into account the higher cost of these implants, we would not recommend the routine use of OxZi femoral heads in primary THAs.Level of EvidenceSystematic review and meta-analysis of therapeutic studies I-III.  相似文献   
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Background and purpose — Impaction bone grafting (IBG) in revision hip surgery is an established method in restoring bone stock deficiencies. We hypothesized that local treatment of the morsellized allograft with a bisphosphonate in cemented revision would, in addition to increased bone density, also reduce the early migration of the cup as measured by radiostereometry (RSA).

Patients and methods — 20 patients with aseptic cup loosening underwent revision using the IBG technique. The patients were randomized to either clodronate (10 patients) or saline (10 patients, control group) as local adjunct to the morsellized bone. The outcome was evaluated by dual-energy X-ray absorptiometry (DXA) during the first year regarding periacetabular bone density and with radiostereometric analysis (RSA) for the first 2 years regarding cup migration.

Results — 2 patients were lost to follow-up: 9 patients remained in the clodronate and 9 in the control group. Less proximal migration was found in the clodronate group compared with the controls, measured both over time (mixed-models analysis, p = 0.02) as well as at the specified time points up to 2 years (0.22?mm and 0.59?mm respectively, p = 0.02). Both groups seemed to have stabilized at 1 year. We found similar bone mineral density measured by DXA, and similar RSA migration in the other directions. No cups were re-revised.

Interpretation — Local treatment of the allograft bone with clodronate reduced early proximal migration of the revised cup but without any measurable difference in periacetabular bone density.  相似文献   
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The role of stasis in venous disease is undisputed, yet surprisingly, its haemodynamic quantitation remains largely undefined. We investigated the phenomenon of venous stasis in the lower limb upon sitting and standing and project its implications to economy class aircraft passengers. 26 normal limbs, 13 subjects, age 29-54, selected after duplex, plethysmography and ABPI, had peak[V(peak)], mean[V(mean)] and minimum[V(min)] velocities, volume-flow[Q(venous)], pulsatility index [PI(venous)] and diameter obtained on horizontal, sitting (as in economy aircraft seats) and standing with duplex, at popliteal, femoral[FV] and common femoral[CFV]veins [differences in median %]. V(peak), V(mean) and Q(venous) decreased from horizontal to sitting in the CFV [57%, 71%, 31%, respectively], FV [51%, 70%, 34%] and popliteal [31%, 58%, 42%] (all, p<.001). V(peak),V(mean) and Q(venous) decreased further from sitting to standing in the CFV [26%, 44%, 25%, respectively], FV [21%, 42%, 27%] and popliteal [14%, 42%, 20%] (all, p <.001). Diameter, V(min) and PI(venous) increased from horizontal to sitting in the CFV [50%, 63%, 38%, respectively], FV [39%, 23%, 66%] and popliteal [21%, 14%, 84%] (all, p <.001)]. Diameter, V(min) and PI(venous) increased further from sitting to standing in CFV [10%, 22%, 19%, respectively; p =.004], FV [12%, 68%, 2%[ns]; p <.001)] and popliteal [14%, 50%, 24%; p =.017]. In all postures: V(peak), V(mean), Q(venous) and diameter at CFV exceeded FV (p <.025) and popliteal (p <.001) ones; also those at FV exceeded the popli-teal ones (p =.003), except for the diameter on horizontal. V(min) in popliteal was higher than in CFV (p =.003) or FV (p <.025), on horizontal and standing. PI(venous) in CFV was lower than in FV or popliteal (p <.025) on sitting. Right to left differences non-significant. [Wilcoxon(+Bonferroni) test: significance at p <.025] A shift from horizontal to sitting generates a most significant attenuation in Q(venous),V(peak) and V(mean) linked to a reciprocal increase in V(min), PI(venous) and vein diameter, with further exacerbation on standing. V(peak),V(mean) and Q(venous) decline with distance from groin enhancing venous stasis in the periphery. By restricting activation of the natural venous pumps, sitting cramped during long flights may protract the status of haemodynamic stagnation sustained on dependency which paired with marked venous dilatation generates a milieu that may promote thrombogenesis.  相似文献   
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To evaluate the effect of endometrial injury on clinical outcomes in subfertile women with repeated implantation failures (RIF) undergoing assisted reproduction. In this prospective nonrandomized controlled trial, 103 subfertile women with RIF were included. Fifty-one underwent endometrial injury through hysteroscopy in the early follicular phase of the previous cycle and 52 underwent the standard protocol without any intervention. Live birth and miscarriage were the primary outcomes. Clinical and in vitro fertilization (IVF) cycle characteristics, were also compared between groups. Both groups were comparable in terms of baseline and cycle characteristics. Live birth rates were significantly higher in the study, compared with the control group (18/51 vs. 8/52, odds ratio (OR)?=?0.25; 95% confidence interval (CI)?=?0.10–0.64; p?=?0.020), although miscarriage rates were similar (7/51 vs. 10/52, OR=?0.25; 95%CI=?0.12–0.66; p?=?0.452). The rest of the outcomes parameters were comparable between groups. Logistic regression analysis revealed that endometrial injury and duration of subfertility were independent predictors of live birth after control of other variables (OR?=?2.818; 95%CI?=?1.044–7.605; p?=?0.041 and OR?=?0.674; 95%CI?=?0.461–0.985, p?=?0.042, respectively). Endometrial injury induced through office hysteroscopy in the preceding cycle in subfertile women with RIF improves live birth rates.  相似文献   
68.

Purpose

Catheter guidance is a vital task for the success of electrophysiology interventions. It is usually provided through fluoroscopic images that are taken intra-operatively. The cardiologists, who are typically equipped with C-arm systems, scan the patient from multiple views rotating the fluoroscope around one of its axes. The resulting sequences allow the cardiologists to build a mental model of the 3D position of the catheters and interest points from the multiple views.

Method

We describe and compare different 3D catheter reconstruction strategies and ultimately propose a novel and robust method for the automatic reconstruction of 3D catheters in non-synchronized fluoroscopic sequences. This approach does not purely rely on triangulation but incorporates prior knowledge about the catheters. In conjunction with an automatic detection method, we demonstrate the performance of our method compared to ground truth annotations.

Results

In our experiments that include 20 biplane datasets, we achieve an average reprojection error of 0.43 mm and an average reconstruction error of 0.67 mm compared to gold standard annotation.

Conclusions

In clinical practice, catheters suffer from complex motion due to the combined effect of heartbeat and respiratory motion. As a result, any 3D reconstruction algorithm via triangulation is imprecise. We have proposed a new method that is fully automatic and highly accurate to reconstruct catheters in three dimensions.
  相似文献   
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The aim of this study was to evaluate retrospectively the usefulness of transvaginal sonography for the detection of endometrial disease in postmenopausal women without symptoms. The study involved 750 postmenopausal women aged 52-65 (mean 58.5). None of them were on hormone replacement therapy and all had had amenorrhea for more than two years. Transvaginal sonography was performed in 750 women. An endometrium of < 5 mm and non-measurable (627 women) was not investigated further. The 627 cases of this group were reassessed one year later. In the remaining 123 postmenopausal women with suspicious endometrium > 5 mm, 19 endometrial polyps (7.13%), one cervical polyp with extension in the cavity (0.8%), 90 endometrial atrophies (73.17%), ten atrophic endometritis (8.13%), two simple hyperplasias (1.62%), and one hyperplasia with atypia (0.8%) were found. Transvaginal sonography is an efficient and acceptable noninvasive method for the early detection of endometrial pathology in postmenopausal asymptomatic women.  相似文献   
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