A subtalar implant device includes a rounded end cap region, a threaded region having threads, and a core having a first end, a second end, a core exterior and a longitudinal axis. The threads can have a shape that varies between the first end and the second end of the core. For example, the threads can include an outer edge having an edge width that varies. Further, the threads can include a thread depth that can vary between the first end and the second end of the core. A thread radius of curvature varies at a different rate than a core radius of curvature. The core can define one or more core apertures that extend through the core at various angles relative to the longitudinal axis. In one embodiment, two core apertures are positioned at an angle greater than zero degrees relative to each other.