A sprained ankle is one of the most common orthopedic injuries. A sprain is actually an injury to the ligaments of the ankle joint, which are elastic, band-like structures that hold the bones of the ankle joint together and prevent excess turning and twisting of the joint. During normal movement, the ligaments can stretch slightly and then retract back to their normal shape and size. Sprained ankles often result from a fall, sudden twist, or a blow that forces the ankle joint out of its normal position. Ankle sprains commonly occur while participating in sports, wearing inappropriate shoes, or walking or running on an uneven surface. The anterior talofibular ligament is one of the most commonly involved ligaments in this type of sprain. Excessive swelling can compress nerves and blood vessels causing numbness and coldness in the extremity. Is there numb and tingly sensation at times other than after elevating the foot on the stool at work. It may be just this position - stretching posterior leg tissue including sciatic nerve. How about when you lie flat and elevate the foot.