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101.

Background

Short-term and intermediate-term wear rates for highly cross-linked polyethylene (HCLPE) liners in total hip arthroplasty (THA) are significantly lower than published rates for traditional polyethylene liners. The aim of this study was to report the longest-to-date follow-up of a specific HCLPE liner.

Methods

A series of 35 THAs using a specific HCLPE liner were reviewed. Anteroposterior radiographs were reviewed for femoral head penetration, the presence of femoral and/or acetabular osteolysis, long-term survival, total wear, and wear rates in all patients.

Results

The average patient age at time of surgery was 70 years with an average follow-up of 10 years (118 months; range, 7.2-13.4 years). The mean wear rate in our cohort was 0.07 mm/y. Total wear was 0.71 mm over the study period. No hips showed evidence of osteolysis in any zones. Survivorship at latest follow-up was 100% with all-cause revision as an end point.

Conclusion

The wear rate of HCLPE liners continues to be lower than published wear rates for traditional polyethylene and continues to reaffirm the acceptably low wear rates using HCLPE acetabular liner in primary THA.  相似文献   
102.

Background

Many cost drivers of total knee arthroplasty (TKA) have been critically evaluated to meet the heightened quality-associated expectations of performance-based care. However, assessing the efficacy of the different modalities of skin closure has been an underappreciated topic. The present study aims to provide further insight by conducting a meta-analysis and systematic review evaluating the rates of common complications and perioperative quality outcomes associated with different suture and staple skin closure techniques after TKA.

Methods

The present study was conducted in accordance with both the Preferred Reporting Items for Systematic Reviews and Meta-analyses Statement and the Cochrane Handbook for meta-analyses and systematic reviews. Primary outcome measures evaluated rates of common complications associated with primary TKA. Secondary outcome measures evaluated wound closure time, direct surgical costs, and cosmetic and knee function outcomes.

Results

Our meta-analysis demonstrated that skin sutures had a higher likelihood of superficial and deep infections, abscess formation, and wound dehiscence. Conversely, staples had a higher tendency for prolonged wound discharge. A systematic review of wound closure times and overall resource utilization demonstrated that wound closure was faster and more cost-effective with skin staples than sutures.

Conclusion

Primary skin incision closure with staples demonstrated lower wound complications, decreased wound closure times, and an overall reduction in resource utilization. Given these outcomes, the use of staples after TKA may have several subtle clinical advantages over sutures.  相似文献   
103.
目的:系统研究人骨髓间充质干细胞(hBMSCs)体外成骨诱导分化过程中成骨相关基因的表达变化。方法:应用密度梯度离心法分离hBMSCs,取第2代细胞通过流式检测及多向诱导分化方法进行干细胞鉴定;应用RT-PCR法对hBMSCs在体外成骨诱导不同时间点的成骨相关基因表达进行检测。结果:第2代hBMSCs表达间充质干细胞表面标志CD44、CD90,具有成脂和成骨分化潜能。成骨相关基因在诱导早期部分表达,中期均有表达,基因表达大部分在14天达高峰,与矿化相关的基因表达在21天达高峰。结论:hBMSCs体外成骨诱导过程中成骨相关基因呈动态表达,其表达时序与成骨细胞生理发育基本相似。  相似文献   
104.
目的 探讨经皮血管成形术(percutaneous transluminal angioplasty,PTA)治疗血液透析动静脉内瘘狭窄的有效性,比较介入手术后联合培哚普利对再次狭窄率的影响.方法 对17例自体血管动静脉内瘘狭窄患者行血管造影,其中15例行PTA.7例患者PTA术后每日口服培哚普利8 mg,7例患者未服用任何血管紧张素转换酶抑制剂(angiotensin converting enzyme inhibitor,ACEI)和血管紧张素Ⅱ受体拮抗剂(angiotensin receptor blocker,ARB).术后对患者进行随访,观察球囊扩张术的并发症、技术成功率、临床成功率和半年通畅率.结果 17例患者均在动静脉内瘘成熟并使用3个月以上发生功能不良,造影见狭窄多位于动静脉吻合口附近及头静脉透析用穿刺段.经PTA治疗后,造影显示狭窄段血管扩张、再通,治疗技术成功率达86.7% (13/15),临床成功率达93.3%(14/15).2例患者因为导丝无法通过近乎闭塞段血管而选择其他手术方式.穿刺部位血肿2例,无医源性血管破裂,无继发血栓形成.随访6个月,14例获得临床成功的患者内瘘半年通畅率为64.3%,其中培哚普利组发生再次狭窄1例,对照组发生再次狭窄4例.结论 PTA是治疗动静脉内瘘狭窄安全、有效及微创的方法,联合口服培哚普利可能有助于降低术后再次狭窄率.  相似文献   
105.
目的了解和分析原发性乳腺癌患者不同治疗阶段创伤后成长的变化,为临床及延续护理提供参考。方法采用创伤后成长评定量表对80例原发性乳腺癌患者于手术前1d(T1)、手术后第3天(T2)、术后首次化疗(T3)及末次化疗(T4)进行调查。结果患者T1~T4的创伤后成长得分依次为83.04±20.90、62.84±19.21、59.58±13.78、67.85±13.51;不同时段总分及各维度得分比较,差异有统计学意义(P0.05,P0.01)。结论手术及化疗对患者的创伤后成长造成一定负性影响,随化疗结束及治疗效果的显现,患者创伤后成长呈上升趋势,护理人员应根据其特点实施针对性干预,以有效地提升其创伤后成长水平。  相似文献   
106.
The purpose of this meta-analysis was to identify if patient-specific instrumentation (PSI) could increase the accuracy of the correction in high tibial osteotomy (HTO) and to explore the assessment indices and the necessity of using a PSI in HTO. A systematic search was carried out using online databases. A total of 466 patients were included in 11 papers that matched the inclusion criteria. To evaluate the accuracy of PSI-assisted HTO, the weight bearing line ratio (WBL%), hip-knee-ankle angle (HKA), mechanical medial proximal tibial angle (mMPTA), and posterior tibial slope angle (PTSA) were measured preoperatively and postoperatively and compared to the designed target values. Statistical analysis was performed after strict data extraction with Review Manager (version 5.4). Significant differences were detected in WBL% (MD = −36.41; 95% CI: −42.30 to −30.53; p < 0.00001), HKA (MD = −9.95; 95% CI: –11.65 to –8.25; p < 0.00001), and mMPTA (MD = –8.40; 95% CI:−10.27 to −6.53; p < 0.00001) but not in PTSA (MD = 0.34; 95% CI: −0.59 to 1.27; p = 0.47) between preoperative and postoperative measurements. There was no significant difference between the designed target values and the postoperative correction values of HKA (MD = 0.14; 95% CI: −0.19 to 0.47; p = 0.41) or mMPTA (MD = 0.11; 95% CI −0.34 to 0.55; p = 0.64). The data show that 3D-based planning of PSI for HTO is both accurate and safe. WBL%, HKA, and mMPTA were the optimal evaluation indicators of coronal plane correction. Sagittal correction is best evaluated by the PTSA. The present study reports that PSI is accurate but not necessary in typical HTO.  相似文献   
107.
108.
Locked plate technology has evolved in an effort to overcome the limitations associated with conventional plating methods, primarily for improving fixation in osteopenic bone. The development of screw torque and plate-bone interface friction is unnecessary with locked plate designs, significantly decreasing the amount of soft tissue dissection required for implantation, preserving the periosteal blood supply, and facilitating the use of minimally invasive percutaneous bridging fixation techniques. The locked plate is a fixed-angle device because angular motion does not occur at the plate screw interface. The use of locked plate technology allows the orthopaedic surgeon to manage fractures with indirect reduction techniques while providing stable fracture fixation. The secure 'feel' of locked plates, ease of application, and the low incidence of complications noted in early clinical reports have contributed to the proliferation of this technology. Along with reports of clinical successes, as the use of fixed angle/locked plates has increased, clinical failures are being noticed. This review will focus on the biomechanics of locked plate technology, appropriate indications for its use, laboratory and clinical comparisons to conventional plating techniques, and potential mechanisms of locked plate failure that have been observed.  相似文献   
109.
目的探讨低剂量及常规剂量螺旋CT扫描在检出磨玻璃密度肺结节(ground-glass nodule,GGN)的数目、边缘、内部结构与周边结构是否在统计学上存在显著差异。方法对经常规剂量(200mA)与层厚(5mm)螺旋CT扫描发现GGN患者56例同时行肺部低剂量(30mA)螺旋CT扫描,所得图像分别重建2mm、1mm,并按结节直径5mm,5~10mm,10mm不同大小分组,记录结节数目、边缘、内部特征以及周边结构等。结果低剂量与常规剂量螺旋CT扫描在检出GGN的数目、边缘、内部结构与周边结构无统计学意义。结论30mA低剂量螺旋CT扫描及层厚2mm可对GGN作出较好的判断,值得在早期肺癌筛查中应用。  相似文献   
110.
ObjectivesTo explore patterns of recurrence, muscle invasion, and disease specific mortality in patients with bladder carcinoma in situ (CIS) who responded to an induction course with intravesical bacillus Calmette-Gúerin (BCG) immunotherapy.MethodsBetween June 1985 and December 2003, 104 patients (mean age 67 years) were diagnosed with either pure (38 patients) or concomitant (66 patients) CIS. Patients who responded to one (92 patients) or two (12 patients) induction courses of intravesical BCG instillation were included in the study. Response was determined and monitored by routine periodic bladder biopsies. Outcome of patients and the effect of various prognostic parameters were assessed after a median follow-up of 75 months.ResultsThe 5- and 10-year recurrence-free survival rates were 63% and 54%, respectively. The 5- and 10-year muscle-invasive-free survival rates were 79% and 77%, and the 5- and 10-year disease-specific survival rates were 90.5 and 85.8%, respectively. Median time to recurrence, muscle invasion, and disease-specific mortality was 18, 19, and 40 months, respectively. Pure and concomitant CIS were associated with a similar outcome. The recurrence of nonmuscle-invasive tumor did not increase the risk for muscle invasion or mortality.ConclusionsPure and concomitant bladder CIS share similar biologic behavior. Muscle-invasive disease is expected in about 25% of the BCG responders followed for long time periods and disease-specific mortality in 15%. Tumor recurrence, whether nonmuscle-invasive or muscle-invasive, follows a similar time table suggesting that these are not sequential but parallel and independent processes.  相似文献   
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