The elbows on my Blackarachnia broke at the "top", of the socket, the area closest the upper arm. Removing the elbows caused new cracks to form and now both forearms sockets are missing a chunk. They will not stay together no matter what glue I use.
I believe the issue is that the ball is putting too much stress on the socket, something didn't come out quite the right size.
I suggest if you have a copy of this figure, be very careful when handling it from now on. I've had two other people say that this happened to theirs.