Factors Influencing the Varus Deformity of Humeral Head in Proximal Humerus Fractures and Its Relation to Functional Outcome

BackgroundFractures of the proximal humerus represent approximately 4% of all fractures and 26% of humerus fractures. Proper reduction, stable internal fixation and early initiation of physiotherapy help to achieve a good functional outcome. Aim of this study was to evaluate varus fixation/malunion of proximal humerus fractures and its relation to functional outcome.Materials and MethodsWe retrospectively evaluated 32 patients with proximal humerus fractures who were surgically treated between 2015 and 2017 at tertiary care hospital. We divided the patients into three groups on the basis of the neck-shaft angle as valgus group, normal group and varus group to observe the influence of neck-shaft angle on efficacy. Patients were evaluated for functional outcome using the Constant–Murley score.ResultsTwo-part fractures had better functional outcome (Constant score = 75.15) compared to three parts with the moderate functional outcome (Constant score = 68.81) and the four-part fracture had poor functional outcome (Constant score = 52.66). After 6 months of follow-up, 13 patients had a neck-shaft angle of less than 126°. The functional outcome is significantly better among patients with normal neck-shaft angle and had a mean Constant score of 76.63 as compared to patients with varus deformity had a mean Constant score 60 (p = 0.001). 10 patients did not have medial support, in which 08 patients had neck-shaft angle less than 126° and 2 had a normal neck-shaft angle.ConclusionHigh fracture comminution, improper restoration of medial continuity causes varus deformity of the humeral head and it leads to poor functional outcome. The small sample size is the limitation of our study.     

Research on the Grinding Energy Density in a Jet Mill

Raw materials are used in many industrial technologies. The raw material frequently has to be prepared as an intermediate with an appropriate particle size distribution, which requires the use of grinding. In grinding processes, energy consumption is a very important profitability criterion for the applied particular size reduction technology. The paper describes the comminution process that takes place in the jet mill using a modified form of the thermodynamic theory of grinding. In this theory, new material characteristics have been added: the surface and volumetric density of grinding energy. The thermodynamic theory is a combination of the classical Kick’s theory and the modified form of Rittinger’s theory. The tested physical magnitudes are a measure of the energy consumption of the grinding process. They describe the energy that must be provided in the grinding process to overcome interactions between particles related to the volume and surface of the material. Knowledge of these magnitudes is necessary to model thermomechanical phenomena in the solid state. The paper presents the results of research on comminution in a jet mill, on the basis of which the values of the tested material magnitudes were determined. It is graphically shown how the values of the tested magnitudes depend on the grain size of the ground samples.     

Digital image processing versus visual assessment of chewed two-colour wax in mixing ability tests

Two-colour chewing gum and wax have been widely used as test foods to evaluate the ability to mix and knead a food bolus. The mixing of the colours has been assessed by computer analysis or by visual inspection. Reports contradict each other about whether computer analysis and visual assessment could equally well discriminate between the masticatory performances of groups of participants with different dental status. This study compares the results of computer analysis of digital images of chewed two-colour wax with the results of visual assessment of these images. Sixty healthy subjects participated and chewed on red-blue wax for 5, 10, 15 and 20 chewing strokes. The subjects were divided into three groups of 20, matched for age and gender, according to their dental status: natural dentition, full dentures and maxillary denture plus implant-supported mandibular overdenture. Mixing of the chewed wax was determined by computer analysis of images of the wax and by visual assessment of the images by five examiners. Both the computer method and the observers were able to distinguish the mixing abilities of the dentate subjects from the two denture wearer groups. Computer analysis could also discriminate the mixing abilities of the two denture groups. However, observers were not able to distinguish the mixing abilities of the two denture groups after 5, 10 and 15 chewing strokes. Only after 20 chewing strokes, they could detect a significant difference in mixing ability.     

石膏用量用法的实验研究

应用配位滴定法测定了石膏煎出液中Ca²⁺含量,对石膏的应用剂量、粉碎度、煎煮时间与煎出量的关系进行了观察比较。结果表明,石膏应用剂量以10～20g为宜,粉碎度60目以上为佳,60目以上细粉不必先煎,40目以下粗粉仍需先煎。     

微型外固定架结合有限内固定治疗38例46处开放性粉碎性掌指骨骨折分析

目的 探讨应用微型外固定架结合有限内固定治疗开放性粉碎性掌指骨骨折方法及疗效.方法 自2002年以来对38例46处手开放性粉碎性掌指骨骨折应用微型外固定架治疗.结果 术后随访6个月至2年,无骨不连及骨髓炎并发症,临床愈合时间平均6周,手功能恢复按TAM标准评价优良率达78.9%.结论 微型外固定架结合有限内固定治疗手部开放性粉碎性掌指骨骨折创伤小,固定可靠,愈合率高,利于早期功能锻炼,有良好的治疗效果.     

Determining chewing efficiency using a solid test food and considering all phases of mastication

ObjectivesFollowing chewing a solid food, the median particle size, X₅₀, is determined after N chewing cycles, by curve-fitting of the particle size distribution. Reduction of X₅₀ with N is traditionally followed from N ≥ 15–20 cycles when using the artificial test food Optosil^®, because of initially unreliable values of X₅₀. The aims of the study were (i) to enable testing at small N-values by using initial particles of appropriate size, shape and amount, and (ii) to compare measures of chewing ability, i.e. chewing efficiency (N needed to halve the initial particle size, N(1/2-Xo)) and chewing performance (X₅₀ at a particular N-value, X_50,N).Design8 subjects with a natural dentition chewed 4 types of samples of Optosil particles: (1) 8 cubes of 8 mm, border size relative to bin size (traditional test), (2) 9 half-cubes of 9.6 mm, mid-size; similar sample volume, (3) 4 half-cubes of 9.6 mm, and 2 half-cubes of 9.6 mm; reduced particle number and sample volume. All samples were tested with 4 N-values. Curve-fitting with a 2nd order polynomial function yielded log(X₅₀)-log(N) relationships, after which N(1/2-Xo) and X_50,N were obtained.ConclusionsReliable X₅₀-values are obtained for all N-values when using half-cubes with a mid-size relative to bin sizes. By using 2 or 4 half-cubes, determination of N(1/2-Xo) or X_50,N needs less chewing cycles than traditionally. Chewing efficiency is preferable over chewing performance because of a comparison of inter-subject chewing ability at the same stage of food comminution and constant intra-subject and inter-subject ratios between and within samples respectively.     

均匀设计法优选连翘超微粉碎工艺的研究

目的均匀设计法优选连翘超微粉碎工艺技术参数。方法采用单因素考察各粉碎工艺参数的范围,结合均匀设计、逐步回归法优选超微粉碎工艺条件。结果逐步回归方程为Y=41.083-1.029X2,r=0.9998;参照粉碎工艺参数范围及生产实际,选择连翘超微粉碎工艺条件为粉碎时间18min,温度？10～10℃,水分5%～9%,介质填充率60%～70%,预测粒径D50为22.56μm,验证粒径D50为22.81μm。结论超微粉碎工艺条件参数与粒径相关性良好,均匀设计法对超微粉碎工艺具有较好的指导意义。     

响应曲面法优化墨旱莲三萜总皂苷提取工艺研究

目的：利用响应曲面法优化墨旱莲三萜总皂苷提取过程,比较普通粉碎与超微粉碎对墨旱莲三萜总皂苷提取过程的影响。方法通过单因素试验探讨了粉碎度、提取时间及乙醇体积分数对墨旱莲三萜总皂苷提取率的影响,利用响应曲面法优化提取工艺。结果最佳提取工艺参数：药材为超微粉碎12分钟的粉末,提取溶剂为70%的乙醇溶液,提取时间为44分钟。结论超微粉碎技术可显著提高墨旱莲三萜总皂苷的提取率,所优选提取工艺稳定可行,适于工业化推广。     

超微粉碎技术对三七药材粉碎效果及有效成分含量的影响

该实验主要研究了超微粉碎技术对三七药材粉碎效果及有效成分含量的影响。以三七微粉粒径大小为指标,利用马尔文粒径测定仪测定粉碎不同时间所得到三七微粉的粒径并采用HPLC-ELSD对三七超微粉碎前后,人参皂苷Rg₁,Rb₁和三七皂苷R₁的含量进行了测定。结果显示超微粉碎2 h的药材粉末粒径均一,达到了细胞级粉碎,D₅₀约为9.599 μm,粒径分布为单峰,粉碎0.5,1,1.5 h的粒径分布均为双峰;超微粉碎0.5,1,1.5,2 h所得三七微粉中3种皂苷类成分总量分别为7.7%,7.5%,7.5%,8.3%,普通粉碎所得三七药粉中的3种皂苷总量约为5.0%,通过以上实验可以看出：超微粉碎与否对三七粉粒径均匀度及其主要成分含量有很大影响;与普通粉碎药粉相比,超微粉碎2 h药粉粒径较为均一,3种皂苷含量明显增加,为临床减少三七用药剂量及合理利用资源提供依据;但其皂苷总量与粉碎时间不成正比关系,可以结合粒径大小需求选择不同的粉碎时间。     

不同粒径三七粉体物理特性及体外溶出行为的比较

目的:比较三七细粉和超微粉体物理特性及有效成份体外溶出行为的差异,为三七超微粉体的粒径控制与应用提供试验依据。方法:通过测定三七细粉和超微粉体的粒径、吸湿性、粉体的形貌结构、流动性等物理特性和体外溶出行为,研究三七粉体的粒径对其物理特性和体外溶出行为的影响。结果:随三七粉体粒度的减小,其比表面积及孔隙率增加,吸湿性增加,流动性减弱;微粉Ⅰ有效成分的溶出速率和累积溶出量均高于其它粉体。结论:适度的微粉化能促进三七有效成分的充分利用,超微粉碎技术应用于三七具有可行性和必要性。