This is Dr. Christian. Welcome to JustAnswer. Have you tried any other treatments beside rimadyl?
Thank you for that information. Hip arthritis is difficult because she is probably mentally completely normal but her body is failing her. Eventually, that arthritis becomes so painful and it becomes so difficult to walk that euthanasia is a very human option. Dogs like to run and being in constant pain is a poor quality of life. If you are unable to adequately control her pain and she has a lot of difficulty getting up or walking around then euthanasia is a good decision. There are a few other things you can combine with the glyco flex and rimadyl that might help some:
Omega 3 fatty acids, found in fish oil capsules at your local pharmacy, are also good for skin as well as joints. One capsule daily for life is necessary.
Adequan is an injection typically given twice weekly for 3 weeks or so then as needed afterward. It has minimal side effects and can be very effective in treating and slowing down the progression of arthritis. Here's a link about it:http://www.petplace.com/drug-library/polysulfated-glycosaminoglycan-adequan/page1.aspx