I have the daily struggle of animating suture and synthetic ligaments. I enjoy a challenge :0
Here is one I did animating suture.
Here is one animating a ligament.
As you can see its less than perfect, but I am getting by. My solution is to create a spline, attach the object using path deform, then animate the spline. The main problem I have with this technique is that the object deforming along the path slides up and down when I animate the spline. I can get away with this when its a cylinder. But when it is a box with a texture you can see the object sliding around. I have little control and have to use 'percentage along path' and 'stretch' to compensate, along with some After Effects trickery to hide the mess. Another issue is passing the vertices with a bezier vertex type through holes, this creates wavey string animations. On top of all that I need to be able to deform objects to squash through holes while following the path. For this I use the FFD box modifier but... its very tricky to get the desired results.
Does anyone have any better ideas? If anyone replies to this post I salute you!