Dear Texan,
Some basic advise from a non-physician.
First, find out what is wrong with your ankle, what is causing the pain, what is the structural problem, what is the diagnosis. If you have medical insurance, I recommend finding the best three orthopedic surgeons in your area (seeking out those who cater to sports injuries, in the process); visiting all of them; and asking many questions as to diagnosis, prognosis, treatment options, rate of success of each treatment option and so forth. Don’t be shy; I have found orthopedic surgeons to be extremely receptive to intelligent questions; they have even expressed to me that they appreciate them as they have found that the more knowledgable patient is often the better patient. And, frankly, it allows them to put the burden of decision back in your hands (the patient’s hands).
A good orthopedic surgeon, upon examination and listening to you, should be able to exactly trace on your leg/ankle/foot with his or her fingernail, or finer instrument, the exact path of your pain; and explain precisely, structurally, what is happening and what the problem is.
Knowing what the problem is, will guide you in how to treat it.
Second, assuming the health of your ankles is “normal” and you can go forward with your hike, I pass on to you two things I learned on the trail (trial?) about ankle sprains and avoiding them, which helped me immensely and which I gleaned through my own experience (I know, you haven’t said you have a sprained ankle; nor what your problem actually is; I’m moving on to a common problem; while hoping you don’t have an abnormal problem):
(a)Solidify your feet when going downhill on steep terrain--by this I mean strive to keep the foot at a 90 degree angle to your foreleg--make, in essence, a platform, and dig in with your heels if need be--while also using your foreleg muscles, on the front and outside of your leg and ankle to keep the front of your foot, and the outside edge of your foot, "up" (ie, at 90 degrees--remember, an ankle sprain is usually a "turn" of the ankle, where the outside edge of the foot catches on something, gets caught, and your ankle rolls forward over your ankle--thats the basic movement). In short, consciously use your muscle power to keep your feet in "safe" positions, stable positions--rather than those which tend to lead to "turning over" one's ankle. In a sense, "surf" down the more extreme terrain, on your heels if need be, digging in with your heels if need be.
In connection with this notion of stability, and the foot as platform (the plane and angle of which you consciously determine), a good lightweight boot with a firm sole, something with a steel shank, or half-length steel shank (and maybe even a fiberglass shank)will help immensely in creating a platform and, as a general rule, help you conserve muscular strength in the foot and lower leg, and in and around their meeting place, the ankle. Boots don’t have to be unacceptably heavy to have these positive features (eg, the Danner Mountain Light II). Having a soft sole or platform, which does not have sufficient rigidity, will lead to your foot, in effect, “bending” over every uneven surface, which, in turn, is inconsistent with the “platform” concept (and will lead to extreme foot fatique in rocky terrain).
(b)As as a general rule, keep your feet "spaced", shoulder width or wider. This will give you, generally speaking, the stongest possible base and best balance. Conversely, don't, if at all possible, let your feet come together, if it can be avoided; close feet (feet close together), when hiking and otherwise, creates the least stable base and leads to both sprained ankles and falls, as we teeter-totter, as if on a knife edge, then topple over. Take the broader, stronger stance.
(c) Take some care to always keep your knees slightly bent (again, I am referring to when one is actively navigating a steep descent). This lowers your center of gravity, gives you somewhat better balance and control, and leave you in a significantly better position to recover (creates a better potential for recovery) should something start to go wrong (eg, ankle problem, knee problem, a potential fall, a fall in progress, etc) than otherwise.
So, see the doctors.
Then, enjoy your hike.
Sincerely–Paul English.
Paul English