In vivo measurement of stress-strain distribution in the ligament using arthroscopic images

我们已经开发出一种测量方法，可应用于体内测量的应变分布在ACL使用关节镜。该方法从运动物体的图像流中重建运动物体的3D形状和变形。我们称之为改进的运动捕捉方法。它消除了相机校准过程的需要。在初步研究中，我们应用该方法进行ACL的体外测量。对尸体膝关节进行改良，暴露其ACL进行观察，并将小的黑色纸标记物沿着肉眼观察到的纤维束贴在ACL上。将膝关节锁定在一个特殊的膝关节运动模拟器夹具中并移动。前交叉韧带的形状由多个摄像机从不同角度同时记录。从单个视频帧，ACL和一些纤维束的变形的3D动画与计算机软件。这种方法可以看出纤维束在什么状态下承受张力。它还深入了解了在进行体内测量之前必须解决的问题。我们认为这项技术可以与关节镜结合使用。

We have developed a method of measurement that might be applied to in-vivo measurement of strain distribution in the ACL using arthroscopy. The method reconstructs the 3D shape and deformation of a moving object from its image streams. We call it the modified motion capturing method. It eliminates the need for camera calibration processes. In a pilot study, we applied the method to perform in-vitro measurement of the ACL. A cadaver knee was modified to expose its ACL for observation, and small black paper markers were affixed to the ACL along the macroscopically observed fiber bundles. The knee locked in a special knee motion simulator jig and was moved. The ACL's shape was recorded simultaneously by multiple video cameras at different angles. From individual video frames, 3D animation of the deformations of the ACL and some fiber bundles were made with computer software. The method made it possible to see in what state the fiber bundles bear tension. It also gave insight into the problems that must be solved before in-vivo measurement can be done. We think it possible to use this technique in conjunction with arthroscopy.