Question: Our patient had aseptic loosening of the tibial component of his knee replacement. He underwent a revision of the joint (tibial component). How would I code for him? Washington Subscriber Answer: You might be tempted to list 996.41 (Mechanical loosening of prosthetic joint) for this patient, but this code isn't the right choice. Listing 996.41 indicates that the patient has a complication, but in your patient's case this condition is no longer present because it was treated by the hospital. Instead, list V54.81 (Aftercare following joint replacement surgery). You should also list V43.65 (Organ or tissue replaced by other means; joint; knee). This status V code should be sequenced after V54.81 but doesn't need to immediately follow. Why not use V58.43 (Aftercare following surgery for injury and trauma) since the injury is coded 996.41 and V58.43 includes conditions classifiable to 800-999? You should select the aftercare code more specific to the aftercare provided which in this case is V54.81 for the joint replacement.