Extensor mechanism allograft in total knee arthroplasty
Female oriental 80 years old patient underwent primary total knee arthroplasty for osteoarthritis in 1997 by another hospital. It initially evolved well, but later presented infection leading to septic loosening of the prosthesis, which was diagnosed in 2006. In 2007 she started being followed-up in our hospital. She presented, at this time, range of motion of 10-80°.\nAs the patient presented symptoms of chronic infection associated with loosening of the components, treatment with review in two-steps was chosen according to our hospital protocol.\n,\n The patient underwent removal of the prosthesis, thorough debridement and spacer with cement associated with vancomycin.\nDuring the procedure, it was necessary to resect a large part of the patellar tendon that was found damaged by the infection, the extensor mechanism becoming consequently compromised. Throughout her treatment, she was also accompanied by the hospital's infection service that indicated antibiotic therapy. The cultures the first cleaning showed no bacterial growth and the infection was controlled, with normalization of inflammatory activity (ESR and CRP). Thus, the patient was submitted two months after the second time with revision arthroplasty and transplantation of the extensor mechanism allograft.\nThe graft consisted of quadriceps tendon-patella (full) - patellar tendon-anterior tibial tuberosity (ATT). The graft was obtained from the Tissue Bank of IOT-HC/FMUSP, having been previously prepared and frozen, without viable cartilage. The technical details of the surgery and the initial postoperative were similar to those of case 1. We point out the differences between them: the bone plug fixation was performed with ATT flexible steel wires and we chose to perform patellar allograft replacement by a technique identical to that of a patellar component in a primary arthroplasty.