Arsenic content in the femur head of the residents of southern and central Poland

Arsenic content was assayed in the samples of the femur head of the people living in southern and central Poland (Kraków, n=13; Silesian region, n=13; Łódź, n=12). The average age being 68.7±8.7 yr. Arsenic content in the femur head was determined applying the hydride generation atomic absorption spectrometry (HG-AAS) method after microwave mineralization. The average arsenic contents in the femur head of the residents of the Łódź, Kraków, and Silesian regions were 0.41 μg/g, 0.37 μg/g, and 0.18 μg/g, respectively. No correlation has been found between arsenic content in the femur head and the content of other metals. Neither the age nor sex of the people tested affected the arsenic content in the femur head.     

X-ray diagnosis of aseptic necrosis of the femur head in adults at the preclinical stage

The time course of an x-ray picture from the normal bone structure up to the appearance of positive x-ray signs of aseptic necrosis of the head of the femur (ANHF) was followed-up. The former, appearing long before the development of clinical signs of disease, were foci of the rarefaction of a round or oval shape in the upper, central parts of the head of the femur, and along its periphery in somewhat dense or normal structure of the head of the femur.     

病灶清除植骨联合DHS内固定治疗股骨近端囊肿

目的:探讨病灶清除植骨联合动力髋螺钉(DHS)内固定术治疗股骨近端囊肿的临床疗效及意义。方法:自2006年3月至2012年6月共有17例股骨近端囊肿患者在我院接受治疗并有完整随访,全部患者均应用病灶清除植骨联合DHS内固定术手术治疗。结果:平均随访时间18个月(14-60个月),病灶植骨处平均愈合时间7个月(6-8个月)。平均手术时间182分钟(90分钟~282分钟),术中平均出血量340 mL(100~700 mL)。切口全部一期愈合,术后病灶处均达到骨性愈合,骨密度均匀,17例均未出现骨囊肿复发及内固定断裂,未发生股骨头坏死及股骨近端骨折,按Harris髋关节功能评分标准,优良率为100%。结论:病灶清除植骨术联合DHS内固定治疗股骨近端囊肿操作简单,术中出血少,并发症少,疗效确切,是治疗股骨近端骨囊肿,降低其复发率和预防病理性骨折的一种有效方法。     

The importance of femur/acetabulum cartilage in the biomechanics of the intact hip: experimental and numerical assessment

Experimental studies have been made to study and validate the biomechanics of the pair femur/acetabulum considering both structures without the presence of cartilage. The main goal of this study was to validate a numerical model of the intact hip. Numerical and experimental models of the hip joint were developed with respect to the anatomical restrictions. Both iliac and femur bones were replicated based on composite replicas. Additionally, a thin layer of silicon rubber was used for the cartilage. A three-dimensional finite element model was developed and the boundary conditions of the models were applied according to the natural physiological constrains of the joint. The loads used in both models were used just for comparison purposes. The biomechanical behaviour of the models was assessed considering the maximum and minimum principal bone strains and von Mises stress. We analysed specific biomechanical parameters in the interior of the acetabular cavity and on femur's surface head to determine the role of the cartilage of the hip joint within the load transfer mechanism. The results of the study show that the stress observed in acetabular cavity was 8.3 to 9.2 MPa. When the cartilage is considered in the joint model, the absolute values of the maximum and minimum peak strains on the femur's head surface decrease simultaneously, and the strains are more uniformly distributed on both femur and iliac surfaces. With cartilage, the cortex strains increase in the medial side of the femur. We prove that finite element models of the intact hip joint can faithfully reproduce experimental models with a small difference of 7%.     

散居型西藏飞蝗九个地理种群形态特征的数量分析

为阐明西藏飞蝗Locusta migratoria tibetensis Chen散居型地理种群数量性状的地理变异,将散居型西藏飞蝗9个地理种群雌、雄个体的前翅长度(E)、后足股节长度(F)、头宽(C)、前翅长度与后足股节长度比值(E/F)、后足股节长度与头宽比值(F/C)5项形态特征参数进行系统聚类分析和主成分分析....     

Length estimate for KNM-ER 736, a hominid femur from the lower pleistocene of East Africa

Our knowledge concerning stature in earlyHomo is scanty. In this paper, based on comparison with the fossil femur KNM-ER 999, an estimate of 482 mm femur length is derived for KNM-ER 736, the latter dating from the Lower Pleistocene. From comparison with other fossil and modern femora, KNM-ER 736 appears to be the longest hominid femur so far recovered from a site of Early Pleistocene age. Moreover, the estimated femur length is higher than the published mean values of most modern populations. Provided that trunk and head proportions were not radically different from modernH. sapiens, the finding would suggest that a stature similar to that of modern man was already reached by East AfricanHomo as early as about 1.6 Myr before present.     

Anatomical Feature Segmentation of Femur Point Cloud Based on Medical Semantics

Feature segmentation is an essential phase for geometric modeling and shape processing in anatomical study of human skeleton and clinical digital treatment of orthopedics. Due to various degrees of freedom of bone surface, the existing segmentation algorithms can hardly meet specific medical need. To address this, a novel segmentation methodology for anatomical features of femur model based on medical semantics is put forward. First, anatomical reference objects (ARO) are created to represent typical characteristics of femur anatomy by 3D point fitting in combination with medical priori knowledge. Then, local point clouds between adjacent anatomies are selected according to the AROs to extract boundary feature point (BFP)s. Finally, the complete model of femur is divided into anatomical regions by executing the enhanced watershed algorithm guided with BFPs. Experimental results show that the proposed method has the advantages of automatic segmentation of femoral head, neck and other complex areas, and the segmentation results have better medical semantics. In addition, the slight modification of segmentation results can be achieved by adjusting a few threshold parameter values, which improves the convenience of modification for ordinary users.     

A histopathological and morphometrical study of femur head cartilage in Wistar rats treated with prednisolone

An analysis was made of histopathological developments in femur head cartilage in a group of Wistar rats receiving a daily intra-muscular injection of 2.5 mg prednisolone. This group was divided into four experimental batches, each consisting of 6 rats. Batches were sacrificed at 15, 30, 60 and 90 days after the start of the experiment. Degeneration of the femur head cartilage was observed from the start of the experiment (15 days), and gave rise to chondrocyte necrosis by 90 days. Structural modifications are shown morphologically and morphometrically.     

Compression or tension? The stress distribution in the proximal femur

Background  

Questions regarding the distribution of stress in the proximal human femur have never been adequately resolved. Traditionally, by considering the femur in isolation, it has been believed that the effect of body weight on the projecting neck and head places the superior aspect of the neck in tension. A minority view has proposed that this region is in compression because of muscular forces pulling the femur into the pelvis. Little has been done to study stress distributions in the proximal femur. We hypothesise that under physiological loading the majority of the proximal femur is in compression and that the internal trabecular structure functions as an arch, transferring compressive stresses to the femoral shaft.     

Albino corpus cardiacum extracts induce morphometric gregarization in isolated albino locusts, Locusta migratoria, that are deficient in corazonin

Abstract.  The neuropeptide [His⁷]-corazonin, present in the central nervous system and corpus cardiacum, is known to mimic a 'gregarizing' effect on phase-related morphometric ratios (hind femur length/maximum head width and fore wing length/hind femur length) when injected into locusts reared in isolation. However, an albino strain is known to exhibit phase-specific changes in these ratios in response to rearing density, although it is deficient in [His⁷]-corazonin. To examine whether there is a second factor responsible for this phenomenon, perhaps a corazonin-like factor that has lost its dark-colour inducing activity, methanol extracts of corpora cardiaca taken from crowd-reared albino nymphs of Locusta migratoria are injected into isolated-reared second-stadium albino nymphs and reared to adults in isolation. The hind femur length/maximum head width and fore wing length/hind femur length ratios are significantly different from those of control oil-injected counterparts, and shift significantly towards the values typical for crowd-reared gregarized individuals. The results indicate that the corpora cardiaca contain a factor similar to [His⁷]-corazonin, although it has no dark-colour inducing activity.     

Bending vibrations of the femur and the oscillatory behavior of a cemented femoral hip endoprosthesis

The paper presents a novel method for recording amplitude and phase of 6D-vibrations of a spatial pendulum over a wide frequency range (10 Hz up to 20 kHz). The six degrees of freedom of the pendulum mass were monitored by three electrodynamic stereo pickups. At rest, the tips of the needles and the pendulum's center of mass defined the reference system with respect to which the oscillations of the mass were recorded in terms of their amplitudes and phases. Its small dimensions, constant transfer characteristics, linearity, high dynamics, and virtual lack of reaction onto the moving system over the entire frequency range provided the advantages of the measuring system. This method was used to analyze the spatial 6D-vibrations of the head of a cemented femoral hip endoprosthesis when the femur was stimulated to bending vibrations. The head of the prosthesis carried out axial rotational vibrations at every frequency used to stimulate the femur. The amplitudes of the axial rotations of the cortical bone were small in comparison to the ones of the prosthesis head, indicating that axial rotational vibrations following femur bending vibrations mainly stressed the spongiosa and the cement layer. This was observed over the entire frequency range, including at the low frequencies relevant for gait. Over the low-frequency range, as well as at some of the higher resonance frequencies, stationary instantaneous helical axes characterized the vibrations. The measurements suggest the mechanism that the interface "implant-bone" may already be stressed by axial torsional loads when the femur is loaded by bending impacts that are known to occur during walking.     

SL-R柄人工股骨头置换术与股骨近端防旋髓内钉治疗老年不稳定型骨质疏松性股骨粗隆间骨折的疗效比较研究

目的:探讨股骨近端防旋髓内钉、SL-R柄人工股骨头置换术两种术式治疗老年不稳定型骨质疏松性股骨粗隆间骨折的应用效果。方法:选取2015年1月-2017年6月间于河北医科大学附属秦皇岛市第一医院行手术治疗的老年不稳定型骨质疏松性股骨粗隆间骨折患者98例,以数表法将患者随机均分为对照组(n=49)和观察组(n=49)。其中对照组采用股骨近端防旋髓内钉,观察组采用SL-R柄人工股骨头置换术。比较两组患者临床各项指标、手术前后髋关节功能评分以及术后并发症发生情况。结果:观察组手术时间、术中失血量均高于对照组,但住院时间、开始负重时间则低于对照组(P0.05)。观察组术后并发症发生率为4.08%(2/49),低于对照组的18.37%(9/49)(P0.05)。术后1个月、3个月时患者髋关节各项评分相比术前均有升高,术后3个月的各项评分高于术后1个月(P0.05);观察组术后1个月、3个月各项评分均高于对照组(P0.05)。结论:在老年不稳定型骨质疏松性股骨粗隆间骨折患者治疗过程当中,采用SL-R柄人工股骨头置换术可减少住院时间,疗效确切,无严重并发症,且可改善髋关节各项功能评分。     

Influence of cartilage cap modelling on FEM simulation of femoral head stress]

The present study reports on the finite element analysis (FEA) of the femoral head in a process of preparation for a program for the realistic simulation of correctional osteotomies of the proximal femur. While the material properties have been studied extensively, only few publications consider the influence of the cartilage layer geometry on FE stimulation of the hip joint. Various models of the femoral head with and without the cartilage layer are generated and analysed. On looking at the maximum surface stresses, we found a strong influence of the cartilage layer and the subchondral osseous layer on the magnitude of the von Mises equivalent stress. The model with an anatomically realistic cartilage layer and compact bone shows stresses of between 4 and 5.5 MPa, depending on the position of the joint, while the model with a concentric cartilage layer has a maximum von Mises stress of 0.8 MPa. Only on simulation of a "realistic" cartilage layer, with a maximum thickness at the "pole" and minimum thickness at the "equator" do the changes in stress distribution--determined by changes in the position of the femoral head--become visible. Owing to major artefacts and the inability to create a realistic cartilage layer, voxel-based models of the femur are not suitable for the simulation of the femoral head surface.     

Growth Studies and Ageing Methods for Adult Triturus vulgaris L. and T. cristatus Laurenti (Urodela, Salamandridae)

Growth of adult newts in southwestern Sweden has been studied from 1969 to 1972 in two ways: (1) The age of alcohol-preserved specimens has been determined by counting dark zones, which are thought to indicate hibernations, on transverse sections of bones (femur or humerus); and average body length and head width of the different age classes have been recorded and compared; (2) Free-living individuals have been identified by their ventral pattern, and body length and head width in different years have been recorded for each specimen. There was generally a small annual increase in body length and in head width, although the individual variation was large because some do not grow at all. Differences in growth were found between years, between populations and between sexes. It is concluded from these results that size should not be used for estimating the age of adult newts.     

Some anthropometric studies of the femur of the male West Malaysian Chinese

Measurements and indices were made on 120 male West Malaysian Chinese femora. The findings are compared with appropriate ones from some Eastern and Western series. The Chinese femur is smaller than all the other groups listed except for the Japanese femur. There is a high degree of significance between the maximum and bicondylar lengths of the Chinese femur against those of the Australian aborigine, Maori and White American. The head of the femur is greater in the Maori and White American than the Chinese. The platymeric index is nearly as high as the White American. The difference in the robusticity index of the femur between the Australian aborigine, Maori, White American and the present series is small. The collodiaphyseal angle of the Chinese femur is large being greater than the Australian aborigine, Finn and White American. The angle of torsion of 11.8° is within the range for Westerners with a high incidence of retroversion unlike the Australian aborigine and Maori where no retroversion is seen. Although most of the means of the measurements and indices of the femur show a highly significant difference between the present series and some of the other groups listed there is a wide overlap for measurements of the Chinese femur to be used for racial identification.     

Influence of interface condition and implant design on bone remodelling and failure risk for the resurfaced femoral head

Resurfacing of the femur has experienced a revival, particularly in younger and more active patients. The implant is generally cemented onto the reamed trabecular bone and theoretical remodelling for this configuration, as well as uncemented variations, has been studied with relation to component positioning for the most common designs. The purpose of this study was to investigate the influence of different interface conditions, for alternative interior implant geometries, on bone strains in comparison to the native femur, and its consequent remodelling. A cylindrical interior geometry, two conical geometries and a spherical cortex-preserving design were compared with a standard implant (ASR, DePuy International, Ltd., UK), which has a 3° cone. Cemented as well as uncemented line to line and press-fit conditions were modelled for each geometry. A patient-specific finite element model of the proximal femur was used with simulated walking loads. Strain energy density was compared between the reference and resurfaced femur, and input into a remodelling algorithm to predict density changes post-operatively. The common cemented designs (cylindrical, slightly conical) had strain shielding in the superior femoral head (>35% reduction) as well as strain concentrations (strain>5%) in the neck regions near the implant rim. The cortex-preserving (spherical) and strongly conical designs showed less strain shielding. In contrast to the cemented implants, line to line implants showed a density decrease at the centre of the femoral head, while all press-fit versions showed a density increase (>100%) relative to the native femur, which suggests that uncemented press-fit implants could limit bone resorption.     

基于形态特征的中华稻蝗生物地理学分析

为研究中华稻蝗形态特征与地理特征的关系,选取中华稻蝗体长(LB)、头长(LH)、前胸背板长(LP)、前胸背板宽(WP)、前胸背板侧片长(LLP)、前胸背板侧片高(HLP)、前翅长(LEL)、后足股节长(LF)、后足股节宽(WF)和后足胫节长(LT)等10个性状,采用电子游标卡尺测量其长度进行比较,使用SPSS11.5统计软件进行体长方差分析、各个性状在不同种群间的多重方差分析以及各性状间与海拔高度间的相关性分析。结果显示:9个中华稻蝗种群分为南方组、北方组及一个过渡种群,雌雄虫中北方种群的体长均明显小于南方种群;各性状测量值呈现出随纬度增加而减少的趋势;10个性状中除前胸背板长、前翅长、后足股节长和后足胫节长与海拔高度之间的相关性不显著之外,其余性状均与海拔高度呈现显著的正相关。结果表明,秦岭的分隔是造成南北方种群形态特征产生差异的主要原因;体型较大、后腿股节较宽的中华稻蝗更有利于在高海拔环境生存。     

Detection of numerous CC and Cc membranes in the femoral condyle

The authors (1,2) discovered a two-membrane system in the head of the femur and its distal condyles (Copf et al. ^1,2,3). The one membrane serves the hydrodynamic principle. It was termed the CC membrane. According to the provisional opinion of the authors, the second membrane, which is designated as Cc membrane, serves for exchange of fluid supply of energy and information flow in view of its original perforations. In contrast to the head of the femur, CC membranes are more numerous. The Cc membranes are also more numerous here, but in some cases differ in terms of their elongate form. The first impression indicates a very much more pronounced component of the hydrodynamic system in the region of the femoral condyle.     

The Odocoileus virginianus Femur: Mechanical Behavior and Morphology

Biomechanical research relies heavily on laboratory evaluation and testing with osseous animal structures. While many femora models are currently in use, including those of the European red deer (Cervus elaphus), the Odocoileus virginianus femur remains undocumented, despite its regional abundance in North America. The objective of this study was to compare biomechanical and morphological properties of the Odocoileus virginianus femur with those of the human and commonly used animal models. Sixteen pairs of fresh-frozen cervine femora (10 male, 6 female, aged 2.1 ± 0.9 years) were used for this study. Axial and torsional stiffnesses (whole bone) were calculated following compression and torsion to failure tests (at rates of 0.1 mm/sec and 0.2°/sec). Lengths, angles, femoral head diameter and position, periosteal and endosteal diaphyseal dimensions, and condylar dimensions were measured. The results show that the cervine femur is closer in length, axial and torsional stiffness, torsional strength, and overall morphology to the human femur than many other commonly used animal femora models; additional morphological measurements are comparable to many other species’ femora. The distal bicondylar width of 59.3mm suggests that cervine femora may be excellent models for use in total knee replacement simulations. Furthermore, the cervine femoral head is more ovoid than other commonly-used models for hip research, making it a more suitable model for studies of hip implants. Thus, with further, more application-specific investigations, the cervine femur could be a suitable model for biomechanical research, including the study of ballistic injuries and orthopaedic device development.     

Sensitivity analysis of hip joint centre estimation based on three-dimensional CT scans

In morphological analysis of the femur, the hip joint centre (HJC) is generally determined using a 3D model of the femoral head based on medical images. However, the portion of the image selected to represent the femoral head may influence the HJC. We determined if this influence invalidates the results of three HJC calculation methods, one of which we introduce here.

To isolate femoral heads in cadaver CT images, thresholds were applied to the distance between femur and acetabulum models. The sensitivity of the HJC to these thresholds and the differences between methods were quantified.

For thresholds between 6 and 9 mm and healthy hips, differences between methods were below 1 mm and all methods were insensitive to threshold changes. For higher thresholds, the fovea capitis femoris disturbed the HJC. In two deformed hips, the new method performed superiorly. We conclude that for normal hips all methods produce valid results.