Review Question - QID 8347

A 77-year-old man who had right total knee replacement surgery 2½ years ago has had knee pain since surgery. The pain is diffuse, constant, and made worse with activity. He notes warmth and swelling in his knee. Examination shows a well-healed incision, no erythema, moderate warmth, synovitis, and an effusion. The knee is stable, and has an arc of flexion between 3 and 120 degrees. Radiographs show well-fixed and well-aligned implants. What is the most appropriate next step in management?