Painful Flat Foot (Sinus Tarsi Impingement Syndrome)
Sinus tarsi impingement commonly occurs along with an ankle sprain, or with chronic high arches. With an ankle sprain, the lateral ankle gets stretched, and the medial ankle gets compressed. The compression on the medial side can cause pain in the sinus tarsi, which is the area where the heel bone meets the talus bone in the medial ankle. High arches can also cause impingement of the sinus tarsi.
