This case represents a complete, closed dislocation of the talus, which is an extremely rare injury, although not as rare as those occurring without fracture. With these types of injuries the talus is at significant  risk for avascular necrosis.  This case is especially interesting as the talus is not only completely dislocated, but also reversed in its normal AP orientation. 

Talar dislocations and talar neck fractures of any type have historically been referred to as aviator's astragalus, although the value in assigning this term is only for reading-room entertainment.