Objectives: The aim of the study is to compare short term results between open and posterior arthroscopic post traumatic subtalar joint fusion. Methods: It is a prospective comparative randomized control study of 40 patients suffering from post-traumatic subtalar arthritis admitted to orthopedics and traumatology department of Kasr ALAiny school of medicine, cairo university from January 2018 till January 2020. 20 patients were managed by open fusion (Group 1) another 20 patients were managed by arthroscopic fusion (Group 2).