Woo SH, Goh TS, Ahn TY, et al. - This study was attempted to assess the results of subtalar distraction arthrodesis (SDA) for calcaneal malunion applying a structural freeze-dried iliac allograft (FDIA) compared to using autologous iliac bone. Between March 2006 and December 2017, 57 consecutive cases (51 patients) of calcaneal malunion were retrospectively examined. More favorable clinical and radiologic outcomes were obtained in the autologous iliac bone group, although the union rate was not significantly different between the two groups. There was significantly more loss of radiological parameters due to inferior incorporation and biomechanical properties using FDIA without any ortho biological agent for SDA. The data illustrated that the routine use of FDIA without any ortho biological agents as an interpositional graft for SDA is not recommended when considering the SDA for calcaneal malunion.