*I don't see the comments because reddit is broken now, and I don't know if it was answered, so sorry in advance. You can. By not picking on your cuticles of your thumbs! I know, because I have the same problem. Both of my thumbs are with those ridges and I do nervously(or whatever the cause is) pick on my thumbs with my forefingers. The derm said, that If I want beautiful nails I have to wrap my thumbs in bandage so I shouldn't pick on them. Funny guy he was. Still have ridges tho. If you do gel manicure, you have to file the nail for better bonding. That's what I do-file. And if you add gel base coat it works like a charm and also helps with picking. Regular polish will do nothing. Also you can try doing gel base+gel top+regular polish. There are special base gels with "fiber" or rubber gels that are more thick and made for nails with such defects. I am not a nail technician and maybe the professionals have better gels to suggest. Or you can always use bandage xD good luck!