Knee Implant Dislocation Leading to Major Amputation 13 Years Later

INTRODUCTION: Injury to the popliteal vessels during total knee replacement is rare but can lead to catastrophic outcomes. REPORT: An 81 year old female presented with Rutherford IIb acute left limb ischaemia (ALI) 13 years after total knee replacement. The polyethylene insert in the knee implant had dislocated from the other components and had moved into the popliteal fossa, leading to popliteal artery compression. She underwent emergency multidisciplinary surgery including removal of the polyethylene component, thrombectomy, and popliteal artery stenting, but major amputation was required. The popliteal artery and the stent were removed and submitted to histological analysis. The stent was well expanded but focal malapposition was observed. CONCLUSION: Regular follow up is mandatory in order to anticipate malfunction of the prosthesis and avoid long term complications.