Several variables may contribute to adult-acquired flatfoot deformity, one such variable is the medial column of the foot, which commonly manifest as forefoot varus or supination. The medial column is subjected to considerable loads during gait, and under normal conditions provides dynamic stability during the stance phase of gait. Pathology occurring along the medial column and forefoot can disrupt normal foot mechanics and lead to flatfoot deformity. A careful history and examination can diagnose dysfunction relating to the medial column and forefoot. Specifically, first tarsometatarsal dysfunction can result in malalignment, and loss of first ray stability. It is important to consider all potential sources of medial column insufficiency since dysfunction can occur at any point along its course. Stabilization and joint-sparing techniques may be used to correct multiplanar malalignment of the first tarsometatarsal joint, and offers a powerful means of preserving foot mechanics.