Severe Metallosis with Extensive Soft Tissue Necrosis in a failed Revision Total knee Arthroplasty: A Case Report

Severe metallosis with extra-articular extension and development of soft tissue necrosis has not yet been reported as a complication after total knee arthroplasty. A 92-year-old old diabetic female patient underwent a revision total knee arthroplasty with a Miller-Galante II implant five years before this admission. She suffered from painful swelling and effusion of her left knee joint after a fall three days earlier to the visit, and blackish fluid was aspirated. Her symptoms also deteriorated with development of shiny skin, erythema, and blister formation of the calf, and metallosis with compartment syndrome of the left lower leg was highly suspected. She received an emergent arthrotomy. Massive metallosis with extra-articular involvement along the intermuscular layer and subsequent soft tissue necrosis of the calf were noted. We report this rare late complication after total knee arthroplasty and discuss the possible pathomechanism.