You can cut them with a small dog or cat nail trimmer, or use a dremmel tool. Have quick-stop on hand from a pet store to stop the bleeding if you go to far by accident. Same stuff used for dogs/cats- works fine on bird nails.
If they are preventing her from walking normally, I would cut them aggressively to close to normal length- cut every 2 weeks or so to get them back to where they should be. She was probably kept on wire for along time for them to get that way.
Likely you will need to trim her nails periodically for life- her toes are probably deformed by now due to the nails twisting them, they will not wear normally. Not a big deal, just make sure to look at them every month- and cut anything going an odd direction or forcing her toe(s) the wrong direction.