A subtalar implant that can be expanded/contracted in vivo to adjust the amount of distraction applied to the subtalar joint of a patient and a related insertion device are disclosed herein. More specifically, the subtalar implant can expand both radially and also in the angle between the proximal and distal end of the outer component of the implant. The implant comprises an internal component that allows for the distal or proximal ends of the implant to be manipulated via the insertion device. The subtalar implant and the related insertion device permit a surgeon to adjust the implant construct to suit a particular patient.