Orthopedic Coding Alert

Several CPT surgical modifiers exist for related or unrelated procedures and returns to the operating room (OR) during the global orthopedic surgical period. Yet even when complex orthopedic surgeries result in returns to the OR for complications or anticipated additional procedures, many physicians and coders do not pursue a great deal of reimbursement because they think any postoperative care that falls in the global period may not be billed separately. There are instances when additional billing within the global period is appropriate, and understanding the differences in global modifiers and knowing when to append them is essential to obtaining reimbursement.

Modifiers -78 (return to the operating room for a related procedure during the postoperative period), -79 (unrelated procedure or service by the same physician during the postoperative period) and -58 (staged or related procedure or service by the same physician during the postoperative period) are the CPT modifiers for any return to the OR or procedure conducted by the same physician during the postoperative period. These modifiers also apply when a different physician from within the same professional group, billing under the same tax ID number, treats the patient during the postoperative period.

1. Modifier -78. The rationale behind the -78 modifier is that every surgery includes a preoperative, intraoperative and postoperative component. When two procedures are performed within the same global period, carriers consider it essentially double dipping if they pay twice for global postoperative care.

An example of when to append the -78 modifier occurs when a patient has a total knee replacement (27447, arthroplasty, knee, condyle and plateau; medial AND lateral compartments with or without patella resurfacing [total knee replacement]) that becomes infected post-operatively. The prosthesis is removed, and a temporary methylmethacrylate spacer may be placed between the femur and tibia. This secondary surgical procedure is reported using 27488 (removal of prosthesis, including total knee prosthesis, methylmethacrylate with or without insertion of spacer, knee) with the -78 modifier to indicate the procedure was related to the original surgery.

The above example represents a clear-cut case of the use of -78, but other scenarios blur the lines of interpretation between modifiers -78 and -79. For example, if a patient has a total knee replacement (27447), then falls during physical therapy and does major damage to the prosthetic knee, he or she may have to return to the OR for a revision arthroplasty (27487, revision of total knee arthroplasty, with or without allograft; femoral and entire tibial component). Per Medicares interpretation of the modifiers, the repair of the failed arthroplasty, because it is related to the original arthroplasty, would be coded with a -78 modifier. Yet some commercial carriers will accept the -79 modifier, because [...]