83 yr female. one swollen ankle, burning pain in back of heel and ankle. kidneys, heart, bp good. nearly everyday pitting edema in only one. cause?

ANKLE PAIN: You want to go see a foot specialist such as a podiatrist or foot and ankle orthopedics because you might have a possible fracture, severe ankle sprain, cellulitis or vascular condition. The only way to diagnose these condition is by a physical exam , blood work, cultures if open wound followed with diagnostic/radiographic testing.