Flight feather keeps growing backwards

Jaina has a flight feather that grows in backwards/upside down, even after molts. It doesn't seem to bother her, but at her last checkup the vet said there was slight swelling around the feather follicle because of the way it was growing. I've also noticed that she has to flap harder to fly compared to my male tiel Snow, possibly due to the backwards feather. Is there a way to correct the feather's orientation, or should I just let it be?

Hmm...I am not sure on this one...I know sometimes birds can have a permanently odd follicle...If it is just one, I would keep an eye on it but I am not sure that you can do much....I am just basically trying to bump this thread because I am curious as well and it seems like there should be a solution (just don't know if there is).

Yes, Hmmm...

A backwards feather would imply that it is possibly 180 degrees out of normal position on the wing. IF that is what is in fact happening the feather would not be able to support the feathers on either side nor halt /limit air passing though it because the natural curve of the feather is wrong.

If all true, the follicle is either turned /twisted or has grown in 180 degrees out of phase with all the others. The redness is likely a result of continuous force applied (in the wrong direction) on the feather and as a result the follicle is moving and that likely is causing the swelling.
What too do?
It is possible that the feather has itself twisted in the follicle or the follicle itself has grown in 180 degrees out of phase. In either case cut the Wing Feather approximately 25 mm (1") from its base. Do not cut any Shorter!!!

Be very careful not to cut other feathers or the Wing Structure /Skin. This will greatly reduce the force placed on the follicle, reducing the swelling and the other feathers will shift slightly to fill most of the gab.

With the Feather cut the feather will not molt again until the next natural molt.
It is always possible that your Parrot is itself twisting the Feather as part of normal play, etc...