Re: Subtalar fusion now or later?
There are no real long term consequences of avoiding a subtalar joint fusion besides continued pain. The end result of severe arthritis of that joint is a fusion. Since you are already there, you aren't doing any extra damage that would ultimately change the type of surgery performed or the outcome.
If your subtalar joint is at the end stage of arthritis, there is nothing wrong with multiple cortisone injections per year. This joint, like all other joints, is surrounded by a soft tissue capsule and the injection stays localized to that area. The long term consequences of multiple cortisone injections into a joint is further deterioration of the joint. Just remember, this type of surgery is an elective surgery.....you elect to have it done not the physician. If you do not want to undergo the procedure, you shouldn't go through with it. That being said, I am very certain you would find it very helpful for your current pain since it has very good success with arthritis secondary to calcaneal fractures.
If you truly do not want the fusion at this point, my recommendation is to find a physician that is willing to give you a cortisone injection to make you more comfortable instead of insisting you have the fusion. Believe it or not, physicians like that are out there. Other things that you may want to look into is bracing. An "Arizona brace" is specifically designed to support excessive inversion/eversion motion of the subtalar joint. It is more commonly used for painful flatfoot pathology, but you may have very good success with it as well. It is the motion of the arthritic subtalar joint that is causing you pain and the goal of the brace is to limit that motion. Hope this helps.