Well, that's magical thinking. You see what you want to see.
From my part I don't see any skin teared off excepting the one that was pierced by the knife. And if it was teared off, I fail to see at which point in the video you can notice it's healed since at no moment the camera zooms again on the legs to show they are "intact".
Leaving the magical discussion apart, where does this ritual take place? It looks like some tribe from the pacific islands but I'm not sure.
Also, do you have any idea what religion it belongs too, or what kind of supernatural being they are invoking?
It is around 1:50 onward, the man broke the chicken legs. The legs were almost separated from the chicken.
I think the place is Cambodia. Don't know about religion though. Just a random video I found.