periosteal delamination There is periosteal stripping with edema along the lateral distal tibial metaphysis through the plafond extending anterior and posterior deep to the syndesmotic complex (white arrows); Ive not seen this pattern of injury with high ankle sprain. No fracture. There is partial tear of the Ant Tib Fib ligament (yellow arrow). Partial tear of the cranial fibers of the ATFL (red arrow). I partially torn posterior ligament (blue arrow) to be the cranial fibers of PTFL, but might be the intermalleolar ligament. There is grade I deltoid sprain. Only the CFL is not injured.