Our Buana has the same thing, since he is a puppie.
Every winter his ears get dry, and loose hair.
For Buana there is no medical issue behind it but it looks like the dry air of winter gives the edges of the ears a hard time.
We have tried all kind of things but nothing helps, we stopped finding what to do and let it, and in spring the ears get the hairs back..
But with Buana it does not itch..
You can try almond oil, but you have to start before they ears loose the hairs...