Missouri Subscriber
Answer: You should not report 27599 (Unlisted procedure, femur or knee) for this service, because CPT includes a code that describes this procedure more accurately. You should instead report 27438 (Arthroplasty, patella; with prosthesis).
Patellofemoral joint arthroplasty with prosthesis involves removal of intercondylar notch osteophytes and resurfacing of the femoral trochlea and patella with insertion of patellar and femoral trochlear implants.