Just coded one...those are the codes I used!The way we review arthroscopic knee surgical procedures is to consider if the procedures are done in separate compartments of the knee. If they are, then using multiple codes is accurate with modifier 59 appended to the lesser of the procedures.
There are three separate compartments of the knee:
1. Suprapatellar pouch and Patellofemoral joint
This includes the patella, patellofemoral joint, the trochlear notch of the femur, and the synovial plicae.
2. Medial compartment
This includes the medial femoral condyle, the medial tibia plateau, and the medial meniscus.
3. Lateral compartment
This includes the lateral femoral condyle, the lateral tibial plateau, and the lateral meniscus.
In your scenario, the first code (29880) includes medial and lateral components; The additional work in the patellar area (29875) would qualify as a separate compartment and use of modifier 59 in this case is appropriate.