Immuno-inflammatory tissue reaction to stainless-steel and titanium plates used for internal fixation of long bones

The immuno-inflammatory responses to stainless-steel (21 implants in 20 patients) and titanium plates (22 implants in 20 patients) used in the treatment of long bone fractures were studied immunohistochemically. All fractures healed without complications. In the soft tissue adjacent to the surface of the implants a dark discolouration of the tissue was visible in 18/21 stainless-steel and 20/22 titanium plates. Tissue specimens of all patients contained positive staining for macrophages (CD68-positive cells). Serial sections showed that the majority of cells were found to express the HLA-DR molecule indicating their activation. Many of the macrophages were surrounded by clusters of T-lymphocytes (CD3-positive cells). 17 out of 21 steel specimens and 15 out of 22 titanium specimens showed the infiltration of moderate amounts of cytotoxic T-lymphocytes (CD8-positive cells). Moderate amounts of B-lymphocytes (CD79alpha positive cells) were evident in four patients with steel and six patients with titanium implants. The results of the present study clearly demonstrate the presence of a marked inflammation and tissue reaction in the soft tissue covering stainless-steel and titanium plates used for internal fixation of fractures of long bones independently from the material used.     

A new approach to scaffold fixation by magnetic forces: Application to large osteochondral defects

Scaffold fixation represents one of the most serious challenges in osteochondral defect surgery. Indeed, the fixation should firmly hold the scaffold in the implanted position as well as it should guaranty stable bone/scaffold interface for efficient tissue regeneration. Nonetheless successful results have been achieved for small defect repair, the fixation remains really problematic for large defects, i.e. defects with areas exceeding 2cm(2). This paper advances an innovative magnetic fixation approach based on application of magnetic scaffolds. Finite element modeling was exploited to investigate the fixation efficiency. We considered three magnetic configurations: (1) external permanent magnet ring placed around the leg near the joint; (2) four small permanent magnet pins implanted in the bone underlying the scaffold; (3) four similarly implanted stainless steel pins which magnetization was induced by the external magnet. It was found that for most appropriate magnetic materials and optimized magnet-scaffold positioning all the considered configurations provide a sufficient scaffold fixation. In addition to fixation, we analyzed the pressure induced by magnetic forces at the bone/scaffold interface. Such pressure is known to influence significantly the bone regeneration and could be used for magneto-mechanical stimulation.     

Biotinylation of silicon-doped hydroxyapatite: A new approach to protein fixation for bone tissue regeneration

Silicon-doped hydroxyapatite has been functionalized with biotin molecules as a new methodology for the attachment of proteins, peptides or growth factors through the formation of avidin–biotin complex in this material. Bioceramic biotinylation has been performed by esterification reaction between the OH groups of hydroxyapatite and COOH groups of biotin molecules. Several parameters of the biotinylation, such as the addition of N,N′-dicyclohexylcarbodiimide (DCC), the biotin/bioceramic molar ratio and the activation time, have been studied in order to improve both the amount of anchored biotin on the bioceramic surface and its bond strength. The grafting of biotin on a silicon-doped hydroxyapatite surface was determined using ¹³C nuclear magnetic resonance, Fourier transform infrared spectroscopy and elemental analyses. The results show that the addition of DCC significantly increases both the amount of biotin grafted and the bond strength, because the major part is through covalent bonding. Lixiviation studies in simulated body fluid (SBF) at 37 °C have confirmed such results, showing that the retention grade after 7 days in SBF was of ca. 63%. Fluorescein isothiocyanate–avidin complexation has been performed on three-dimensional (3-D) scaffolds prepared by a rapid-prototyping technique. Confocal microscopy studies show a homogeneous distribution with a higher incorporation rate of the protein over the entire external surface of the biotinylated 3-D scaffold.     

肘前、外侧两种手术入路治疗桡骨头骨折的比较

目的探讨显露桡骨头骨折的有效手术入路。方法采用肘前侧手术入路显露桡骨头并结合微型空心螺钉固定治疗桡骨头骨折12例,其中2例MasonⅢ型骨折的骨折块于前臂完全旋后时位于桡骨头的前侧。采用传统的肘外侧手术入路10例,显露桡骨头骨折并用微型空心螺钉埋头固定。结果前侧手术入路显露骨折时间平均为20．7分,外侧入路显露骨折时间平均为11．6分。按照Broberg和Morrey肘关节评分标准评定手术疗效：前侧入路组优良率为92％,外侧入路组优良率为90％,两组间无明显差异。结论肘前侧入路可有效显露并固定桡骨头骨折,降低桡神经深支损伤的可能性,尤其适用于治疗前臂完全旋后时桡骨头前侧骨折这一特殊类型骨折。两种入路可视具体情况加以选用。     

寰枢椎病变植入物内固定：口咽入路的优势

背景：经口咽入路是治疗寰枢椎病变的传统方法,一直以来都是脊柱外科研究的热点和难点。 目的：为经口咽入路到达颅颈交界区提供直观操作路径,并提供安全操作的解剖学数据。 方法：对尸体标本进行经口咽入路逐层外科解剖,观察解剖层次、组织结构以及相互之间的毗邻关系,以门齿为标志点测量各主要解剖结构与其之间的距离,并测量椎动脉与中线之间的距离以及寰枢椎的形态学结构。 结果与结论：经口咽前入路能直接显露从斜坡中下段至C3椎体上缘的范围,双侧椎动脉到中线的距离C1水平左侧为20.72-29.70 mm、右侧为20.36-28.98 mm,C2水平左侧为13.10-23.00 mm、右侧为13.85-24.02 mm。前结节、齿突前面、齿突后面、硬脊膜、脊髓以及C2椎体前缘和C3椎体前缘与门齿之间的距离分别为69.24-88.16 mm、74.95-96.27 mm、84.77-107.39 mm、87.65-111.45 mm、91.38-116.11 mm、76.21-92.77 mm和78.53-105.13 mm。寰椎长度为(19.8±2.3) mm,齿突高度为(15.9±1.9) mm,最大横径为(10.5±0.6) mm,最大矢状径为(11.5±1.9) mm;枢椎最大横径为(15.1±1.6) mm,最大矢状径为(17.7±1.3) mm,上关节面外缘到中线的距离为(26.1±1.7) mm,横突孔入口与上关节面之间的距离为(8.1±1.3) mm。颅颈交界区的解剖结构复杂,经口咽入路在解剖安全范围内处理颅颈交界区病变存在优势。     

骨折的生物学内固定及内固定材料性能分析

背景：近年来,骨折内固定已经从强调坚强内固定、绝对稳定和解剖复位,转向强调保留软组织血运、相对稳定和解剖轴线排列的生物学固定。 目的：总结不同骨折内固定材料的临床应用特点,分析内固定器置入后的生物相容性。 方法：应用计算机检索CNKI和重庆维普数据库中1990-01/2011-11关于骨折内固定材料的文章,在标题和摘要中以“骨折、内固定、钢板、螺钉”和“松动、断裂、相容性”为检索词进行检索。选择内容与骨折内固定治疗相关的文章,同一领域文献则选择近期发表在权威杂志的文章。初检得到178篇文献,根据纳入标准选择密切相关的24篇进行回顾分析。 结果与结论：随着原材料工业和生物医学的进步,骨科内固定器械的发展迅速。目前绝大多数的医疗机构应用的骨科内固定钢板螺钉的生物相容性和刚度都是相当好的,但不同部位、类型的骨折所选择内固定的材料也不尽相同,这些材料的抗弯曲性、轴向、横向、抗旋转稳定性以及骨折固定后并发症和相容性均不同。骨折生物学固定由于极大地减少了对骨折处软组织的损伤及植骨率,缩短了骨折愈合时间,可显著降低骨折不愈合、再骨折和感染的发生率。      

A new approach to psychopathology

A new approach to psychopathology based on the psychology of integration as applied to psychological states is outlined. Because all raw behavior occurs only in the form of psychological states, all formulations of psychopathology must refer to integrative disorders that are postulated to underlie all pathological or defective behaviors. Disintegration is the one common factor found in all mental disorders. Lack of integration underlies most inadaptability. The classical field of psychopathology, which formerly was limited to the consideration of formal psychiatric disorders, now is expanded to include deficits, imbalances and disintegrations of acute or chronic nature that result in erroneous or less than perfect judgments. Judgment is considered to reflect the quality of underlying integrative processes. Judgmental defects that lead to maladaptive decisions inevitably must result in maladjustment and/or less than perfect performance. It is necessary to differentiate between (a) integrative disorders per se, and (b) the personal-social effects of positive or negative integrations organized by healthy or unhealthy factors. Criminals may be well integrated in their asocial activities, but socially undesirable because organized about the criminal ethic. Postulates are presented that outline the theoretical assumptions upon which integrative psychopathology is based. This approach utilizes classic theories such as the Freudian psychopathology of everyday life when valid and relevant within the larger framework of integrative psychology. A differentiation is made between hierarchical levels of increasingly complex factors that may organize integration.     

A new approach to the treatment of asthma

Asthma is a chronic inflammatory condition. The previous emphasis on bronchodilator therapy, which does not treat the underlying inflammation, may be misplaced. Earlier introduction of antiinflammatory agents, such as corticosteroids or cromolyn sodium, is strongly recommended. Effective suppression of airway inflammation reduces the need for bronchodilator therapy and may reduce the morbidity and, perhaps, mortality of asthma.     

大腿远端前内侧入路在股骨骨折内固定术中应用的影像及解剖学研究

目的 探讨大腿远端前内侧入路在股骨远端骨折内固定术中应用的安全性和可行性。方法 (1)纳入2016年8月-2017年2月河北医科大学第三医院MRI室双侧大腿中下段MRI资料20例40侧进行回顾性研究,其中男12例、女8例,年龄22~59岁,MRI均未见明显异常。扫描范围:自股骨内侧髁水平线(0 cm处)起,至其上方18.5 cm;扫描层厚5 mm、层间距15 mm,共10个扫描层面(Ⅰ~Ⅹ层面)。应用我院影像存储与传输系统(PACS)测量各扫描层面上前内侧手术入路(预计手术的前进路线)与股动脉之间的最短距离。(2)在1具成年男性新鲜尸体标本上,模拟股骨远端骨折前内侧手术入路内固定物置入过程,同时对该入路涉及解剖层次与结构进行应用解剖观察。结果 (1)20例40侧受检者MRI测量:前内侧入路与股动脉之间最短距离测量值左右两侧差异无统计学意义,故合并统计。分析显示,该间距测量值在Ⅰ~Ⅹ层面的分布规律总体呈中间小两头大、上端小下端大的趋势,其最大处位于股骨内侧髁水平线0 cm处(Ⅰ层面)为46.72~49.47(48.02±0.84)mm,其最小处位于股骨内侧髁水平线上方10~10.50 cm范围内(Ⅵ层面)为23.34~25.05(24.35±0.52)mm,手术入路与股动脉间有足够的安全间距。(2)尸体标本模拟手术:股骨远端骨折前内侧手术入路内固定物模拟置入过程顺利,手术操作未侵扰到股血管和股神经及其分支;应用解剖观察证实,该手术入路可沿肌间隙进入,周围解剖层次及结构显露清楚。结论 大腿远端前内侧入路应用于股骨远端骨折内固定术安全可行,这是对传统外侧入路治疗股骨远端骨折的良好补充。     

A finite element analysis of bone plates available for prophylactic internal fixation of the radial osteocutaneous donor site using the sheep tibia model

IntroductionThe strengthening effect of prophylactic internal fixation (PIF) with a bone plate at the radial osteocutaneous flap donor site has previously been demonstrated using the sheep tibia model of the human radius. This study investigated whether a finite element (FE) model could accurately represent this biomechanical model and whether stress or strain based failure criteria are most appropriate.MethodsAn FE model of an osteotomised sheep tibia bone was strengthened using 4 types of plates with unilocking or bicortical screw fixation. Torsion and 4-point bending simulations were performed. The maximum von Mises stresses and strain failure criteria were studied.ResultsThe strengthening effects when applying stress failure criteria [factor 1.76–4.57 bending and 1.33–1.80 torsion] were comparable to the sheep biomechanical model [factor 1.73–2.43 bending and 1.54–2.63 torsion]. The strongest construct was the straight 3.5 mm stainless steel unilocking plate. Applying strain criteria the strongest construct was the straight 3.5 mm stainless DCP plate with bicortical screw fixation.ConclusionsThe FE model was validated by comparison with the sheep tibia model. The complex biomechanics at the bone-screw interface require further investigation. This FE modelling technique may be applied to a model of the human radius and other sites.     

脊柱侧弯后路矫形内固定术的配合与护理

目的探讨脊柱侧弯后路矫形内固定术的配合及护理方法。方法对10例青少年患者行脊柱侧弯后路矫形内固定术,配合医生手术并严密观察病情变化。结果所有患者手术过程顺利,无一例脑脊液漏,脊髓损伤及切口感染等术后并发症发生,术后随访两年脊柱侧弯畸形均得到了明显矫正。结论手术护士熟悉手术步骤,全面掌握各种仪器及器械操作是手术配合成功的关键。完善的术前准备及密切的术中观察是减少脊柱侧弯病人术中并发症的重要因素。     

股骨干骨折钢板内固定治疗失败浅析

目的 探讨股骨干骨折钢板内固定治疗失误的原因。方法 对24例股骨干骨折钢板内固定失败病例(断裂9例、弯曲5例、松动10例)进行回顾性分析。结果 24例病人中22例取出原内固定，采用髓内钉或加压钢板固定，15个月内均获痊愈，2例松动程度较轻者采用管形石膏外固定半年内痊愈。结论 适应证选择不当、技术操作不正确、内固定器材选择不当、功能锻炼不正确以及钢板质量问题是造成股骨干骨折钢板内固定失败的主要原因。     

A new approach to the theory of rubber elasticity

Current polymer network theories do not explain the experimental behaviour clearly. The use of Gaussian distribution might be the reason of this limitation. The approximation of the distribution of the chain vector by a Gaussian function implies non-vanishing probability for chains at full extension and beyond. In the stress-strain relation, the first derivative with respect to strain of the logarithm of the distribution function is involved. For Gaussian distribution this derivative deviates very much from that of the actual distribution especially at higher extensions. The properties of the said derivatives for different distributions were examined. It is observed that the use of the Langevin distribution might be more realistic. A new approach is suggested on this basis. The tensile force per unit cross section, τ, for an extension ratio α at constant volume has the form where an average chain contributes a length L in each of the three mutually perpendicular directions and contains n equivalent free links of length l each. The expression contains no unknown parameter. This equation has great similarity with the empirical Mooney-equation and gives much better agreement with experimental results.