【作者】 樊继宏；

【导师】 朱青安；

【作者基本信息】 第一军医大学 ， 生物医学工程， 2001， 硕士

【摘要】 关节的接触压力与关节创伤，关节退行性变有着密切的关系，临床上有关术式的目的也是为了恢复或减小关节的接触压力，但关节接触压力的测量一直没有较好的直接测量方法。本课题以富士公司生产的压敏片为敏感材料，依据其受力大小的不同而显示不同浓度的红色的显压原理，研制出基于压敏片材料的关节接触压力测量系统，并测量了不同关节内的压力大小和压力分布。 基于压敏片材料的接触压力测量系统所用仪器设备及材料包括高精度扫描仪、高性能计算机各一台，压敏片材料若干。扫描仪将载有受力信息的压敏片扫描进计算机内存储，应用自行编制的程序读出压敏片上受力部位的浓度并将其转换为压力，通过统计软件分析压力数据得出相关结论。 本课题分两部分，第一部分基于压敏片材料的接触压力测量系统的研制，第二部分基于压敏片材料的接触压力测量系统在人体关节压力分析中的应用。系统研制包括系统标定和程序设计。程序设计中开发了浏览任意大小图片、任意范围选定、不同范围的计算方法、模板保存和数据保存等功能；系统标定中，对扫描仪的各项设置作了优化选择，标定出了压敏片的灰度值—压强对应关系曲线。在第二部分，通过应用压敏片材料关节接触压力测量系统，对腕关节三角纤维软骨复合体、桡骨头、腰椎等关节部位作了接触应力测量，分别得出如下结论： 1．在正常情况下，腕部的压力载荷约20％通过尺骨传递，80％通过桡骨传递。当三角纤维软骨复合体水平部分切除后尺骨传递载荷的比例则减小。三角纤维软骨复合体水平部分1/3切除后减小不明显；1/2切除或全部切除后尺骨传递载荷的比例较完整标本显著减小。 2．桡骨头传导应力的大小约占所施加应力的55％。桡骨头切除后，所施加的应力完全由肱尺关节承受，但肱尺关节面不同部位的变化并不一致，肱尺关节外侧关节面应力增加的幅度明显较内侧关节面大，而尺骨鹰嘴中间嵴承受的应力无明显增加。桡骨头传导应力的大小随肘关节的位置不同而异，当肘关节处于伸直旋前位时，肱桡关节的接触面积最大，经饶骨头传导的应力亦最大。 3．前屈时腰椎小关节承载下降，后路韧带拉伸，导致椎间盘内的压力明显升高。后伸时前纵韧带和前纤维环拉伸，后路韧带松驰，小关节面的接触应力明显增大，椎间盘内压减小。更多还原

【Abstract】 Injury or degeneration of human joints associates with change of contact stress in the joints. Joint surgical techniques try to restore or reduce contact stress in abnormal joints. However, there has not been a direct measurement to read both magnitude and contribution of contact stress in human joints. In the present study, a measuring system was developed to measure contact stress of joint using Fuji pressure-sensitive-film, which tested contact force with gray on the film. Contact stress in wrist joint, elbow joint and lumbar facet joints were measured using the present system. Hardware of the measuring system consists of a scanner with high resolution, a computer and Fuji pressure-sensitive-film. Scanner scans Fuji pressure-sensitive-film and transfers image data into computer. Every pixel gradation on Fuji pressure-sensitive-film is transfers into pressure using a custom ~oflware. The study includes two parts. The first part presents how to develop a measuring system of contact stress of joints using Fuji pressure-sensitive-film, including calibration of the system and development of computer program. The optimal set of scanner was analyzed. The curve of gradation-intensity of pressure was obtained. In the computer program, browsing arbitrary size pictures, selecting arbitrary size range, computing pixel, saving templates and data and so on were developed. In the second part, contact stress in wrist joint, elbow joint and lumbar facet joints was measured using the present system. Their conclusions are: 1. Normally about 20% load of the carpus is transferred through the ulna., and the other 800/o is transferred through the radius. The ratio of the load transferred by the ulna is dropped with the section of the transverse part of TFCC. Compared with the intact specimen, after 1/3 section of the transverse part of TFCC, the ratio is not dropped significantly, and after 1/2 or whole section the ratio is dropped significantly. 2. About 55% force of all was transferred through the radial head. Cutting the radial head, the stress is all taken by the humerounlar joint, but the stress at different part of the facet are not the same. The stress at the lateral facet of the humerounlar joint was increased more greatly than that at the medial, and the stress at the middle crest of the olecranon process of unla is not increased significantly. The stress transferred by the radial head is various with the different position of the elbow. When the elbow was extended and the forearm was pronat, the contacted surface of the humeroradius joint was the greatest, and the stress transferred through the radial head is also the greatest. 3. When it is in the flexion position the load of the lumbar minimal joints decreased and the posterior longitudinal ligament extended, thus the pressure of the intervertebral discs is increased significantly. And when it is in the extension position the anterior longitudinal ligament and the anterior fibrous rings extend, whereas the posterior longitudinal ligament is loosen. So as the result the contacted pressure between the minimal joint facet is increased significantly. The intervertebral disks?pressure is also decreased.更多还原