Fig. 2

Adapted from Rogers and Frykberg [27] Staging of the Charcot foot based on anatomic location within the foot. Five anatomic patterns are represented with pattern I affecting the phalanges, IPJs, MTPJs and distal metatarsal bones with atrophic and destructive changes; pattern II affecting the tarsometatarsal joints (Lisfranc’s joint) often with ulceration at apex of collapsed cuneiforms of cuboid; pattern III affecting the naviculocuneiform, talonavicular, and calcaneocuboid joints (Chopart’s joint) with fragmentation of the NC joint and/or subluxation of the CC and TN joints, pattern IV representing the talocrural joint (Ankle joint) and subtalar joints, and pattern V representing involvement of only the calcaneal bone, and particularly avulsion of the posterior tuber of the calcaneus