This is necrosis of soft tissue caused by obstructed circulation
When this happens, pressure builds up in the 
tissues and muscles causing ... Edema of the soft tissue within the compartment 
further raises the... [DOC] [TLE] Complications [PAR] Aseptic Necrosis of the Femur Head ... traction (elongation of a nerve by 
stretching) or ischemic injury (inadequate blood flow).