Poor thing!
I'd look around the aviary and see if there's something sharp they may be getting cut on.
If possible, set up a camera to see if a predator or rat is coming around and injuring them.
I'd treat the wound/injury. Clean it well with chlorhexidine, povidone Iodine or saline, then apply triple antibiotic ointment. It would also be a good idea to cage her within the aviary and place her on puppy pads for a little while until that heals up and the wound can stay cleaner.
Is she eating/drinking o.k.?
If you have photos of your aviary you wish to share, we'll be happy to look at those too and perhaps see something that you are missing.