It could be something as simple as Crohn's Arthritis. When I'm flaring, my ankles swell to the point I can't walk or drive for 2 weeks. My right ankle is usually the worst.
I know there have been others on here whose knees swell all the way down to their ankles. Others have had their fingers swell.
I'm sure yours could be a NUMBER of different things but I (finally) know mine is simply Crohn's Arthritis (inflammation caused by Crohn's) and nothing more.
It's very annoying and I feel your pain.
Diagnosed in October, 2004 at age 32 (misdiagnosed with IBS in 2002)
Current Rx's: Colazal (generic), Omeprazole (PRN), Librax, One-A-Day multivitamin, Probiotic, Omega-3 Fish Oil, Vitamin D, Cranberry pills; Slow Fe (PRN)
Secondary conditions: swelling ankles, extreme fatigue, mouth ulcers, joint pain
Previous/occasional Rx's: Prednisone, Flagyl, Levaquin, Xifaxan, Carafate
4/7/09: Gall bladder removal laproscopic surgery (gall stones)