Maimed & missing cats

I'd like to tell you guys about something that's bothering me a lot. A couple of years ago I noticed a cat in my back yard with a broken back leg. I fed the animal for a while and then it didn't come back any more. I was taking care of five stray cats in my house at the time and let them out in the evening. One day one of them didn't return home, then one morning it showed up with one of her back legs dislocated and dragging it on the ground! I was alarmed to say the least and really didn't know what to do. After about a week her leg went back into place by itself so I kept her inside for a while. Then another of the strays didn't come back home and was never seen again, then another. Before I knew it there was only one cat left!. Again some time went by and I began feeding another stray because it was very hungry. I just hate to see anything go without food. This cat finally brought a tiny little kitten with it one day. I've been feeding them both for about two months now and then the little one disappeared just like all the others but the other one still came for food everyday. Two days ago I went outside and heard a small kitten crying so I looked around and there was the little kitten that I had been feeding but something was wrong. As the kitten came closer I noticed that it's two back legs were either broken or dislocated because the kitten was dragging it's back legs! Now I don't know about you but this is a bunch of baloney and I have to get to the bottom of it. Cats are missing and sometimes needlessly hurt for whatever reason. If the humane society is trapping them and the trap is hurting the cats then something should be done. At this time I just don't know where to start but I will do something soon. When I get more on this I will post the results.