Mid-Term Survivals After Cementless Bipolar Hemiarthroplasty for Unstable Intertrochanteric Fractures in Elderly Patients

Background

Treatment of unstable intertrochanteric fracture in elderly patients remains challenging. The purpose of this prospective study is to determine clinical and radiological results of cementless bipolar hemiarthroplasty using a fully porous-coated stem in osteoporotic elderly patients with unstable intertrochanteric fractures with follow-up over 5 years.

Additive manufactured push‐fit implant fixation with screw‐strength pull out

Additive manufacturing offers exciting new possibilities for improving long‐term metallic implant fixation in bone through enabling open porous structures for bony ingrowth. The aim of this research was to investigate how the technology could also improve initial fixation, a precursor to successful long‐term fixation. A new barbed fixation mechanism, relying on flexible struts was proposed and manufactured as a push‐fit peg. The technology was optimized using a synthetic bone model and compared with conventional press‐fit peg controls tested over a range of interference fits. Optimum designs, achieving maximum pull‐out force, were subsequently tested in a cadaveric femoral condyle model. The barbed fixation surface provided more than double the pull‐out force for less than a third of the insertion force compared to the best performing conventional press‐fit peg (p < 0.001). Indeed, it provided screw‐strength pull out from a push‐fit device (1,124 ± 146 N). This step change in implant fixation potential offers new capabilities for low profile, minimally invasive implant design, while providing new options to simplify surgery, allowing for one‐piece push‐fit components with high levels of initial stability. © 2017 The Authors. Journal of Orthopaedic Research® Published by Wiley Periodicals, Inc. on behalf of the Orthopaedic Research Society. J Orthop Res 36:1508–1518, 2018.     

Long-Term Threshold Stability with Porous Tip Electrodes

Experience with 163 unipolar tined porous endocardial electrodes is reported. One patient required repositioning of the electrode because of exit block. There were no other complications in the entire series of patients. All of the patients had low chronic stimulation thresholds. The mean pulse width 24 hours after implantation was 0.0534 ± 0.0128 ms. Seventy-four patients were restudied six months after implantation. The mean pulse width threshold was then 0.07432 ± 0.0775 ms. Fifty-four patients were evaluated one year after lead implantation. The mean pulse width threshold was then 0.0611 ± 0.0230 ms. The pulse generator was reprogrammed to a lower pulse width in all of the patients. This permitted a substantial prolongation of the pulse generator life. The cost effectiveness of the pulse generator was also greatly improved by pacing with reduced pulse widths. In an additional 16 patients, the voltage amplitude was reduced from 5.0 volts to 2.5 volts. This permitted an even greater increase in the pulse generator longevity.     

Effective Enzyme Coimmobilization and Synergistic Catalysis on Hierarchically Porous Inorganic/Organic Hybrid Microbeads Fabricated Via Droplet‐Based Microfluidics

In this paper, a novel and robust droplet‐based microfluidic method to fabricate poly(ε‐caprolactone)/silica (PCL/SiO₂) hybrid microbeads with hierarchically porous architecture is described and their performance as multienzyme carriers for cascade catalysis is further investigated in detail. In addition to the precise control on size and monodispersity of PCL/SiO₂ microbeads enabled by the microfluidic method, the presence of ammonia as a catalyst for the hydrolysis and condensation of tetraethylorthosilicate makes it possible to manipulate the competition between sol–gel process and solvent extraction and thus adjust the surface porosity of hybrid microbeads, which eliminates the use of porogens/templates and also the complicated post‐treatment. Isothiocyanate‐immunoglobulin G/cyanine 3‐bovine serum albumin (FITC‐IgG/Cy3‐BSA) and superoxide dismutase/chloramphenicol acetyltransferase (SOD/CAT) are coimmobilized, respectively onto hierarchically porous PCL/SiO₂ hybrid microbeads via either physical adsorption or covalent binding. Fluorescence intensity of coimmobilized FITC‐IgG/Cy3‐BSA proves that the proteins/enzymes immobilization amount via covalent binding is much higher than physical adsorption. The enhanced enzymatic activity, total antioxidant capacity, and reusability assay reveal that coimmobilized SOD/CAT exhibits better performance compared with the mono‐immobilized ones, mainly due to their mutual synergistic effect. The excellent results achieved in the work indicate that hierarchically porous PCL/SiO₂ hybrid microbeads are very promising carriers for multienzymatic catalysis.     

新生儿科实施整体护理的对比分析

整体护理是以现代护理观为指导，以护理程序为框架，根据病人身心、社会文化需要而提供的优质护理。为适应现代护理发展需要，作为护理人员必须转变观念，将过去以“疾病为中心”的功能制护理转为以“病人为中心”的整体护理，以提高护理质量，降低护理并发症，为此，我们根据新生儿专科特     

Mechanical Stability of Novel Highly Porous Metal Acetabular Components in Revision Total Hip Arthroplasty

Highly porous metal acetabular components have emerged for revision hip arthroplasty. However, superior mechanical stability over traditional cementless components has not been demonstrated. Three different cementless acetabular components, including 2 highly porous tantalum designs, were inserted into hemipelvis specimens with a superolateral defect. Mechanical testing was performed to failure using a servohydraulic testing machine. The porous tantalum designs exhibited superior stability over the traditional cementless implant (P < .05). There was no difference in mechanical stability between the rigid modular tantalum shell and the more flexible revision tantalum shell (P > .46). In acetabular revision, highly porous tantalum acetabular components provide superior mechanical stability. However, these results suggest that improved frictional resistance is a more important design feature over implant flexibility with this particular implant.     

动静态下仿生型钛种植体界面应力 与疲劳行为的有限元分析

目的：研究静态与动态加载下仿生型种植体骨界面应力分布状况和疲劳行为,为研发能有效地转移应力至周围骨组织的新型种植体提供理论依据。方法：采用CAD（Pro/E Widefire 2.0）软件建立颌骨和钛种植体的三维有限元模型,设置全致密型（1号）和仿生型（2号）两种结构钛种植体,采用Ansys Workbench 10.0软件分析静态与动态加载下种植体骨界面应力分布状况,并对2号种植体进行疲劳行为分析。结果：在相同载荷下,1号和2号种植体在皮质骨区均为高应力区,2号种植体界面最大应力值、高应力区域面积、根端区最大应力值均低于1号种植体,从上至下种植体骨界面应力呈均匀递减趋势。动态加载的界面应力比静态的界面应力高17.15%。两种加载方式下,两种种植体在皮质骨区界面最大应力值无差别;在松质骨区, 1号的界面最大应力值比2号高75.97%;在根端区,1号的界面最大应力值比2号高22.46%,种植体界面最大应力远小于纯钛的屈服强度。2号种植体颈部皮质骨边缘的最大应力值比1号高7.85%,皮质骨边缘的最大应力值未达到皮质骨的屈服强度。预载50~300 N动态载荷,致密芯的安全系数均在10以上,随载荷加大,多孔层的界面应力呈线性增加,动态加载轴向300 N 和颊舌向45°25 N时,多孔层界面最大应力为11.38 MPa。结论：仿生型种植体有利于松质骨区及根端区界面应力转移到周围骨组织,其几何结构设计能耐受正常咀嚼的疲劳载荷,是安全的设计。     

Acetabular component revision using a porous tantalum biomaterial: a case series

Biologic ingrowth can be difficult to achieve in acetabular component revision, especially in cases with significant bone loss. The purpose of this study was to review our clinical results of acetabular component revisions in patients with significant bone loss using a porous tantalum biomaterial. This is a retrospective review of 25 patients. There were 16 females and 9 males with a mean age of 71.7 ± 10.54 years. The mean follow up was 39 ± 11.09 months (range, 28-55 months). All patients in this series had combined segmental and cavitary bone loss, Paprosky type 2 or type 3. Of 22 patients in this series, 21 had a well-fixed and functioning implant at latest follow up. All 21 patients developed ingrowth along the tantalum surface despite compromised host bone. There were no cases of dislocation or aseptic loosening. Porous tantalum appears to be a promising material for use in revision hip arthroplasty to facilitate biologic ingrowth in patients with acetabular bone loss.     

Medpor在颧骨颧弓低平畸形矫正治疗中的应用

目的：介绍高密度多孔聚乙烯（Medpor）在颧骨颧弓低平畸形矫正中的临床应用。方法：对49例先天性或外伤所致颧骨颧弓低平畸形以Medpor作为移植材料,在颧骨颧弓表面贴附充填。结果：随访6月～7年,49例颧部低平畸形均获得矫正,外形效果满意,无感染、假体外露等并发症。结论：Medpor置入颧骨颧弓低平畸形,是一种安全有效的方法。     

不同修复材料在眼眶爆裂性骨折整复中的比较

目的比较不同修复材料在眼眶爆裂性骨折骨缺损修复中的应用。方法采用不同的修复材料：自体骨、羟基磷灰石、Medpor等,分别填充于眶壁骨折缺损处,比较三种材料术后修复情况。结果Medpor具有组织相容性好、韧性大、易于塑形及固定、受区骨组织吸收现象发生率低等特点,术后效果较自体骨及羟基磷灰石满意。结论Medpor在目前眼眶爆裂性骨折整复中是一种安全有效、值得推广的填充材料。