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Knee arthroscopy in which an inverted cyclops lesion is observed. Cyclops lesion consists of a fibrous nodule that forms at the central pivot of the knee following surgeries with an intraarticular approach. The incidence ranges between 1-10% of all knees subjected to anterior cruciate ligament (ACL) ligamentoplasty, though the condition is not always symptomatic. Its most common location is at the tibial origin of the ACL. Only 5 cases involving a femoral origin, as in our case, have been reported in the literature to date.