[The reorienting subtalar arthrodesis]

The subtalar joint is part of what may be called the "lower ankle joint" and can be considered as the weight-bearing part of it. In the case of articular problems such as post-traumatic malunions or congenital abnormalities, a joint fusion limited to the subtalar joint can be indicated. Resection of the joint surfaces for accommodating the bones to achieve sound union results in a loss of height which must be considered and avoided. Fractures of the os calcis also often cause a loss of height of the hindfoot, together with a maloriented heel which is incompatible with functional and stable gait. The technique of fusion in those cases implements full liberation of the calcaneus from the talus for complete tridimensional reorientation which most often results in an equivalent empty space. It is then necessary to stabilize the reorientation achieved, most efficiently by an autologous tricortical bone block taken from the posterior iliac crest at the sacroiliac joint level. The optimal surgical approach is from posterolateral as described by Gallie.