Isolated Medial Displacement Calcaneal Osteotomy for treating talo-calcaneal coalition in flat feet-adult population: Is alignment the main problem? Gastón Slullitel; Manel Fa-Binefa; Pilar Martínez de Albronoz; Anna Oller Boix; Noelia Dopaso González; Antonio Fernandez Cebrián; Manuel Monteagudo;