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The below Coding Clinic for HCPCS 2021 3Q pages 1 - 5 indicate to use CPT 27487 for a revision from a unicompartmental to total knee arthroplasty. This is also published in the CPT Assistant, July 2013.
QUESTION 1
A patient with a previous partial lateral knee replacement (uni-compartmental) developed arthritis in the medial compartment of the patellofemoral joint in addition to collapse of the medial and lateral aspect of the tibia. As a result, she presented for a conversion of a partial knee to total knee arthroplasty. The knee was entered via the previous incision. Osteophytes were removed off the medial femoral condoyle, the undersurface of the patella was resected, and the metal femoral component was removed. Bone was resected from the distal femur.
Next, the tibial implant was removed and bone was resected from the medial aspect of the proximal tibia. This created a flat surface of the tibia. Trial components were placed, followed by placement and cementing of a short stem tibial component down an intramedullary canal for placement. The femoral component and patellar button were then placed and cemented into place. How is the revision from a previous uni-compartmental knee arthroplasty (UKA) to a total knee arthroplasty (TKA) reported?
ANSWER
Assign CPT code 27487, Revision of total knee arthroplasty, with or without allograft; femoral and entire tibial component, for the revision from a unicompartmental to total knee arthroplasty.
This is consistent with the advice published in CPT Assistant, July 2013, that CPT code 27487 with Modifier 52, Reduced Services, is the correct code assignment for a conversion from a unicompartmental to total arthroplasty.
However, it is not appropriate for the facility to report reduced services with Modifier 52 when a procedure, performed under anesthesia, has been completed as intended. Therefore, for facility reporting, CPT code 27487 is reported without a modifier.
Any guidelines issued from the AHA would supersede guidelines from the AAOS.