The authors have studied the complications and long term results of 91 cases of tibio-talar arthrodesis and 43 cases of tibio-talar arthrodesis associated with subtalar arthrodesis. Minor complications such as limited skin necrosis were noted in 13 p. 100 of the cases, and no-fusion occurred in 7 p. 100. The results were satisfactory in 75 p. 100 of the cases, fair in 13 p. 100, poor in 12 p. 100. Most of the poor results were related to painfull subtalar joints after isolated tibio-talar arthrodesis. This happened often following conditions : excessive equinus, protrusion of screws in the subtalar joint, preoperative lesions of the subtalar joint. In cases of associated tibio-tarsal and subtalar arthrodesis, the long term study revealed moderate and painless secondary arthrosis of the mid-tarsal joint. It is concluded that associated fusion of the subtalar joint should always be considered when tibio-talar arthrodesis is indicated.